Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81
Edition: Model Aviation - 1977/03
Page Numbers: 4, 5, 6, 7, 8, 9, 79, 80, 81
Editors Note Zonker just other odd-ball design published merely diferent Designed two aeronautical engineers perfected over series models article provides good pilot briefing best fly fiber glass fuselage foam wing cores available commercially Earlier models balsa fuselage structural design substitution feasible few pictures show installation gear system retracts used follow-on airplane assured flying will compromised way uniqueness airplane appeals THERE IS strange fellow comic strips unusual demeanor keeps cool ludicrous situations making meaningful comments con tributions society contributions often seem offbeat yet strike heart real life situation allowing reader grasp added insight life like think design being unusual meaningful contribution sport hence named after Zonker Harris incorrigible character Doonsbury may wonder what flap about since canards horizontal stabilizer front themain wing have around long time fact Wright Broth ers original airplane canard Wilbur Orville found some advan tages provided tail-first configu ration exactly ones needed help worlds first successful powered air plane lift air Kitty Hawk course other problems imagine must have dinged few wing tips besides later changed conventional configuration easier others work modeling past have canard gliders free flights sailplanes con trol line RC powered ships have regarded oddities 1oday present worlds first competitive canard pattern ship Zonker 40 competitive machine well show-stopper spectators After 91 flights number 2 machine people still walk up obvious doubt faces thinking Did really see fly Indeed does Ever since seeing pictures B-70 Valkyrie air thought such graceful airplane has lingered mind feeling also growing mind Charlie Bair schoolmate grad school got together day de cided challenge should met set some goals keep designing track should simple 2 should fly like pattern ship 3 should look nice 4 should have squirrelly tendencies Since am flying qualities engineer make airplanes fly well Charlie stability control engi neer calculate flying qualities dimensions design both modelers thought challenge within reach feel made build model will final judge Aside challenge designing competitive canard must few advantages over conventional airplane else would little reason fly canard biggest advantage wing horizontal stabilizer canard sur face work together conventional ship Phoenix Kaos Mach begins climb lift tail has decrease push down rotate nose up crease lift wing forces op posing other Zonker 40 lift canard surface must increase raise nose increases lift wing lifting surfaces work together both increase total lift both decrease total lift whether maneuvering flight straight level efficiency lift ing surfaces thus better conven tional design Another advantage entails flinging oil exhaust behind ship rather depositing freshly waxed finish pusher installation natural aircraft balance main lifting surface rear Besides keeping drag producing oil off airplane ab sence high-speed prop-wash over airframe decreases drag Propeller efficien cy pusher installations has also documented being greater same propeller tractor installation lies another benefit hatch top fuselage vir tually innards easily acces sible especially nose wheel linkages Previously have fiddled endlessly nose wheel adjustments under fuel tanks around batteries lots frustra tion some hair loss Zonker 40 steering adjustments made airplane upright sitting gear no fuel tank foam rubber around can start engine taxi around hatch off making small steer ing trim adjustments Elevator rudder throttle trim adjustments can made same way since servos right hind nose gear under hatch Removal wing allows direct easy access tank fuel line No fum bling fuel extensions through hid den firewall out open toughest spot rudder linkage since connects rudder horn engine compartment However once get connected trim adjustments can made servo An easy alter nate cut engine hatch last linkage always accessible statements have made about radio protection during mishaps sudden splintering stops Zonker few designs can put battery front servos next receiver well padded behind heavy stuff 4 Model Aviation Compact well protected radio arrangement easy access adjustments Nylon tub ing brass cable throttle Goldenrod rudder short wire rods elevator steering Elevator linkage split fine adjustment Note battery front servos front receiver better receiver protection during sudden stops sure check flight instructions before doing aerobatics itNtII2 has best possibility survival addition radio gear up front away engine vibration nice retract nose gear well main retracts aileron servo cushioned vibration through wing saddle much closer firewall conventional airplane Propellers seem have habit liking Zonker 40 lasting quite awhile find hard run tool box battery prop since back course design foolproof found out lifted nose up day ground prop asphalt Large rocks dont help too much either Using larger wheels flying off grass recom mended have always disliked control horns pushrods kwik links like flutter ing around breeze causing turbulence drag just being unsightly Zonker has advantage wider fuselage rear enclose rudder linkage ele vators front fuselage wide enough enclose linkages too fact would have difficult time making control horns ex ternal rather internal Pretty neat huh So airplane ends up very clean exterior cylinder head muffler poking out Fixed gear shown keeping goal simplicity however design provisions have made retracts Symmetrical airfoils chosen both wing canard surfaces pro vide similar performance both upright inverted NACA 4-digit airfoils chosen since data necessary calculate stability predict stalling readily available airfoils exhibit pronounced drag bucket low coeffi cients lift therefore simplify de sign process Another reason airfoils used availability computer program draw specified chord lengths Details may found Aug 76 issue Model viation under Richard Perrys Navy Carrier column An 18% thick section chosen give adequate room retracts small drag increase section thickness provides about 17 inches maximum thick ness point retractor fits 18% thickness needed because average chord smaller lot pat tern ship wings due higher aspect ratio 62 18% section NACA 0018 canard surface provides lift before stalling helps during low-speed maneuvers such landing taper ratio 7 mainly structure ease ofconstruc tion looks efficient lowest induced drag would result 42 taper ratio have ever tried cut foam wing 4 taper ratio would appreciate current designs incor porating 6 8 ratios canard surface chosen 20% wing area close rule thumb generally used conventional airplanes distance wing canard adjusted until calculated CG fell just ahead wing peo ple think canard inherently unstable true As long surfaces stick up front balanced sufficiently surfaces back airplane stable actual calculations complex general idea March 1977 5 author Zonker last Nats quite few people flipped sudden sight going backwards~ pattern Though glass fuse foam wing instructions include step-by-step built-up fuselage info Below DuBro muffler new mounting strap tapped pressure Engine rotated bit clear body Entire head exposed better cool ing Goldberg 2-1/2-in spinner cut Out 10-6 Tornado pusher propeller 2345U7895I1231451617 lBIS2052223242526 27 28 29 1/481 BALSA AILERON WINGS AND STAB CONSISTS OF FOAM CORES COVERED WITH BRISTOL BOARD OR 1/16 THE BALSA 3/461/2 HARD WOOD LANDING GEAR MOUNT 30 31 32 33 34 35 36 37 38 BSRDER SCALE IN INCHES LANDING GEAR 2 RESt BALSA WING TIP f BALSA HINGE FARINGS ULL-SIZE PLANS AVAILABLESEE PAGE 96 WING TIP TEMPLATE ING _ROOT TEMPLATE /4 PLYWOOk FIREWALL SECTION AA RUDDERI 1/4 THE 1/4 THK PLT WOOD FIREWALL -AIRCRAFT 1/821/4 BALSAPYLON SD-IS FUEL TANK.....4 STRIPS REQS ENGINE SERVOSTYP STAB 5/B OR IANGLE OF ATTACK 55OMAH ISPORT Os 40 R/C BATTERY21/4DIAWHEELITYPKRAFT MOUNT PACK CARL GOLDBERG 51/2 SNAP ON SPINNER TYP DESIGNED BY'COMPETITION -SD 40 F SCHNUERLE 8/C MILT SANDERS CHARLIE BAIR ONE MOUNT DCL 76 OI2345B78910IIIS134IDlB19DO Dl22232425262725293031 CG just ahead wing distance CG vertical fin lot shorter conventional airplane necessary area fin calcu lated make up shorter moment arm hence large size fin An air foil section NACA 0009 selected fin make effective sheet balsa Effectiveness well area plays important part lateral stability Some might consider engine cool ing problem en joy extensive taxiing before takeoff 5-10 minutes may overheat engine have cooling problem 9 hours running time OS Max Schneurle 40 using fuels 5 22% nitro leisurely taxi Zonker about 100 feet down runway turn around stop Left Pressure retract cylinder arrangement wing main gearmodel plan has fixed gear Servo moved rearward allow retract mounting deepsetto clear tank Zonker Right Gear door closes off against airstream high speeds Simple onedoor design allows gear open door rubber band pull shut Airstream cannot pull open Below Goldberg retract new fiberglass ship Twin gear struts used rather trike ones move wheels forward closer CG Plywood cover plate added Balsa frame capstrips lighten weight decrease balsa expense using plastic covering takeoff Sufficient air flows around engine keep overheating idle power am subject en gines let mention plenty avail able engines will work design should consider using equipped ball bearings since thrust pushes crankshaft toward back plate thrust washer running against bronze bushing aluminum case wont hold up long ball bearings couple engines have left-hand crankshafts available would let use current tractor propellers wide variety sizes would perhaps ideal case however Grish has 2- 3-blade 10-6 pusher props use 2-blade pusher Max 40 am satisfied arrangement Charlie runs same prop regular Max 40 also good results will need hot 40 competition standard 40 will haul around nicely sport flying Mufflers additional consideration standard flow-through expansion chamber just wont turned proper direction air flow because extend prop arc However Slim Line Murphy Airfoil DuBro dont have problem Semco super ex pansion mufflers can also used since shorter regular expansion using DuBro recently tried Slim Line Slim Line fits well has no plates clean already has pressure tap has nice method tighten strap keeps screws potentially sharp edges away fuel line also available bolt-on types variety engines Some mufflers may require cut ting away small part aileron part aikron very effective anyway Though selection mufflers may restricted still plenty choose fuel system simple straightfor ward above works Install tank just like always clunk toward rear airplane fuel line must bend around tank go back engine naturally means longer fuel line normal have no fuel feed problems way still keep line short possible Bending brass tubing face toward rear outside tank will help prevent fuel line kinking Turning tank around face engine March1977 7 Above Second balsa prototype fitted Goldberg retracts Sonic Systems pressure cylinders Note bulkhead moved forward compounded fact main gear well behind CG causing extra load nose Bending main gear forward will solve problem Landing speeds slow because canard no longer has load imposed main gear position can use its full lift hold nose off slower speeds takeoffs will little longer due higher speed necessary nose lift-off stall turn another maneuver re quiring little extra finesse pull off competition style Holding power slightly above idle top maneuver helps cure flop-overs though prop-wash doesnt flow across rudder design currently trimmed canard surface stalls before main wing full back stick slow flight canard stalls nose drops canard surface starts flying again _____________________________________cycle continues nose hunts up down gentle motion sort like boat bouncing across some waves have found Zonker 40 squirrelly airplane uncomfortable flying airplane backwards after number flights body will relax perception will become normal again Having different airplane heck lot fun now have read about advantages disadvantages can either sit back dream about fun could have get busy marshall resources make dream reality Construction As contemplate project let mention fiberglass fuselages foam cores available author may shape own fuselage out balsa cut cores yourself core templates shown plans have several extra fuselages foam cores wings canard interest will also use muffler pressure since Schneurle 40 wont run runs great Again pressure line longer normal shouldnt affect running Fuel tank sizes have tried 6 10 ozs 6 oz ade quate Novice pattern using hot Schneurle 40 10 oz has given flights up 18 minutes regular 40 plenty room either size use rectangular slant style Pylon SS-6 am pleased discussion up now may wonder what insurmountable problem Im holding up sleeve prob- lem arising prop rear big problem may uncomfort able until adjust some flying 8 Model Aviation Zonker First balsa prototype model cardboard covered foam wings fixed gear After near disaster high speed ventral fin added beneath fuse lage Note straight fuse lines Below The fixed gear mounting ship plan Note screw-on cover plate fits over hardwood gear mounting blocks has tried has caused problems tank begins empty Forward accele ration gravity tend push fuel toward rear airplane reversed tank sustained vertical maneuv ers will cause fuel starvation pilot frus tration addition picture yourself flying touch-and-go go around airplane nose rises fuel runs rear tank uncovering clunk engine quits airplane few feet air Thats bad situation can avoided using suggested fuel tank installa tion Above Fixed nose gear reveals Rocket City brake short line routed nose down stick control Very effective simple techniques Since prop-wash does flow over control surfaces sur faces effective low speeds takeoff airplane must moving fast enough canard surface develop sufficient lift get nose up Below Tank held place foam line muffler pressure other carb inlet Wing mounting blocks glued inside saddle Fiberglass saddle requires no reinforcement make available following prices glass fuselage molded fin installed bulkheads$35 plus $2 shipping handling wing cores$l0 plus ship ping $100 ordered separately canard cores $250 plus $50 shipping ordered separately total package plus instructions $4750 plus $2 shipping handling Full-size plans can ordered Model viation Balsa fuselages used two prototypes found fuselage shape ntt critical would recommend stay close basic fuselage area distribution want emphasize wing canard sizes placement sweep must changed make changes own far stability CO placement go size vertical fin has deter mined aero equations really needs big flew slightly smaller fin nearly disastrous results Fuselage Canard Surface design build balsa fuselage lay out bulk head size rear tall enough suf ficiently wide engine/tank installa tion Lay out another set dimensions nose gear mounting point large enough house radio gear two bulk heads will determine overall shape taper fuselage Determine sizes nose bulkhead directly front wing position Either shape bulkheads rectangles put curva ture sides get nicer looking con tour prototype fuselage built 1/2-sq balsa longerons front back four corners bulkheads frame covered 1/8 balsa carved rounded shape nose block cut sanded foam block covered fiberglass cloth Hobbypoxy II engine left exposed easy access can cowled balsa blocks fin cut foam covered epoxied directly onto rear deck fuselage generous fillet used strength along 1/4 dowel running 2 inches up fin inside fuselage layer fiberglass cloth laid inside fuselage under fin provide added strength top hatch cut out provide access radio com partment foam nose block hol lowed soldering gun snug battery fit Once balsa fuselage has de signed fiberglass acquired next step canard surface worked next determine size shape fuselage cut-outs Determine ele vator hinge line according plans draw additional lines 1/4 forward behind hinge line allow balsa facings Cut along additional lines either very sharp Xacto knife foam cutter cuts should angled 150 away hinge line allow 300 elevator movement Since elevators hinged top sur face extra material must cut out allow downward movement eleva tors After elevators have cut determine much would extend inside fuselage cut much off Glue balsa hinge facings sand airfoil shape elevators dry Cover cores cardboard 1/32 balsa using balsa cut 1/4 off leading edge core glue 1/8 balsa cover core glue another 1/8 balsa piece make strong laminated leading edge sure mark core pieces cut apart can keep elevators matched stabi lizer pieces Before proceeding further stab mark fuselage cut outs Set fuselage upright flat table insure fin vertical using build ers square fiberglass fuselage bottom just forward wing cut-out straight parallel wing chord Left Aileron servo arrangement DuBro ball links shown reduce aileron throw Dowel pegs leading edge insure proper alignment Below Talk about access Adjustments can made disassembling ship can taxi hatch off since goop behind plane pick up engine running dont tilt prop runway allow proper incidence alignment canard wing Take fine felt-tip pen lay flat wood blocks Add sub tract blocks until point 1-1/2 continued page 79 March 1977 9 Two nylon bolts hold winguse supports foam avoid bolts denting wing Cutouts aileron horns necessary wing removal Small hole tail cone fuel/oil drain being run type extractor pipe Rossis pipe though have slot cut seem turn better Rossis pipe Tucson club did fine job run ning pylon event complaints heard wasnt enough time between rounds round consisting five heats took about 30 minutes per round repair between rounds just out luck unfortunate another QM contest held same weekend Southern California type contest scheduling doesnt help QM effort gain popularity Tom Christopher won event California Dave Lane 4477 W 136th St. Haw thorne CA 90250213675-3219 Zo nker/Sa nders continued page 9 above table surface Now slide blocks pen along table drawing line side fuselage front bulkhead forward about 7 inches made balsa fuselage same thing wing position shown plans lower pen tip 1 inch above table Check again make sure fuselage remained vertical Now take half stab position ac cording plans along line have drawn trace outline fuselage both sides sport flying adding about 20 incidence drawing cut-out will help longitud inal trim prefer 00O set up myself Proceed make fuselage cut-outs forward part stab ele vators extend fuselage fiberglass cut-outs prefer use No 199 high-speed steel cutter Dremel tool looks like metal saw thicker much smaller diameter making easier handle around curves Remember use goggles whenever cutting Dremel Glue stab halves together fit fuselage Again align fin vertical table builders square care fully align stab tip equi distant top fin same distance above table Small scraps balsa may used hold alignment spot glue Recheck alignment glue permanently add fillet micro-balloons stab tips may added sanded time Also cut eleva tors proper width add balsa cover exposed foam ends accept control horns Cut hinge slots temporarily fit hinges either fuselage rudder may worked next fiberglass fuse lage draw line 2-3/4 fin trail ing edge parallel Mark line bottom cut-out both sides make required cuts Dremel cutter Cut glue balsa hinge posts both fin rudder pieces either balsa glass fuselage sheet balsa could shaped balsa-covered foam core could used save weight used foam core covered 1/32 balsa Use 1/2 balsa cap bottom rudder provide solid mounting rudder horn Ia strip aileron type top rudder may capped 1/16 balsa Bevel forward edge rudder allow 2530o movement either side Trial fit rudder linkage make sure works freely before gluing balsa below rudder cut-out linkage tight fit take time plan carefully exercise some patience qwik link linkage will extend through firewall drill nice big hole prevent hangups Wing Construction pretty much stan dard foam wings Begin gluing 1/4 balsa trailing edge Sand down fair airfoil shape Locate landing gear block placement cut-outs retracts melt out areas March 1977 79 RC Pylon Racing/Lane continued page 20 KGL Ct LA 7th Annual #1 Pre- Season Radio System Check-up FULL TIME TECHNICIANS FACTORY TRAINED ST TEST EQUIPMENT NEW MODERN SHOP ONLY GENUINE FACTORY PARTS SFACTION GUARANTEED [ PRE-SEA SON SPECIAL ONLY $2595 plus postage edadea Perform Transmitter Battery Load Check Perform Transmitter Crystal Frequency Count Perform Receiver Battery Load Check Check Battery Charging Circuit Tune Transmitter R F Check Receiver Sensitivity & Adjust Align Receiver RF IF Stages Check Receiver Logic Align Transmitter Encoder Check Servo Stalled Motor Current Repair parts additional $2595 500 $2095 Less AMA Coupon Repair ______ Net Cost Check Servo Mechanics Adjust Servo Centering Perform System Servo Noise Check Shock Test Complete Airborne System Range Check System System Flight Test Necessary AMA Membership Bonus ~te Kraft Great Lakes Inc 6787 Wales Ave PO Box 2182 North CantonOhio 11720 ca Jack Yarger Mark Porter 216 199-8310 5Caewee BankAmericard Master charge Welcome Zonker continued soldering gun careful control temperature squeezing trigger off use wood blocks cut straight lines ensure proper depth Glue gear mounting blocks Sand cores lightly cover 1/16 balsa favorite material Cut wing tips rough shape glue sand final shape Separate core blocks leading edge put wings block halves Shim up core tips 1/4 scrap balsa proper dihedral sand wing root vertical good fit prick 10-15 holes foam nail ensure firmer glue joint epoxy wing halves together Re-enforce center section 4in wide piece fiberglass sand feather edges cured Cut ailerons proper length sand shape cut hinge slots trial fit wing Trial fit aileron linkages time Also cut aileron servo mounting hole install servo mounts Make hole near leading edge wing keep servo away fuel tank mounts above wing After locating drilling two 1/4 holes fuselage wing mount ing bulkhead place wing wing saddle mark hole locations inside fuselage Install 1/4 dowels wing Glue maple blocks rear wing saddle rear wing mounts Line up wing carefully drill wing mounts pilot hole tap maple blocks 10-24 nylon bolts enlarge wing holes bolts Make engine cut-out time Note shown plans en gine rotated muffler clears body side Rotate just far enough allow easy adjustment needle valve Size shape cut-out will deter mined dimensions engine carb amount rotation Once cut-out roughly shaped can fit engine mount make final cutting shaping muffler strap carb clear ance etc mount engine temporarily mount radial engine mount such Kraft Tatone etc have good experiences Kraft KM-40 Depending size engine cut-out may have insert mount engine through fuselage hole separately install two engine mounting bolts Center en gine mount using 2-in spinner airplane set up Carl Goldberg spinner mark holes firewall remove engine mount Drill mounting holes fuel line throttle link age rudder linkage holes Install motor mount position engine mount proper spinner clearance mark drill tap motor mount Note slight amount downthrust pusher means engine angled up looking towards rear airplane Hatch attachment made easy gluing lip glass cloth balsa along bot tom hatch cloth front effectively seals forward fuselage against air entry single screw top rear will nicely hold hatch down front lip will keep end lifting recommend put small rubber grommet under hatch screw act lockwasher screw grommet have yet come loose Install pine strips along lower edge hatch opening leaving sufficient clearance hatch lip fit inside body also installed partial bulkhead rear hatch keep spreading make rigid pine strips increase strength torsional rigidity fuselage such large hatch used finishing fill balsa grain fill holes sand well recommend priming K&B primer Sand down 400-grit wet dry used dry spray coat K&B super poxy pri mary color Mask spray trim coats rub down wax nice four-foot finish Balance airplane laterally adding weight wing tip necessary Finishing Installation Install radio far forward possible aid balance 80 Model Aviation KRAFT pcs Valid until May 151977 w Put battery nose servos right behind nose gear bulkhead followed receiver provides very good crash protection vibration isolation Depend ing individual radio system switch position may need extension cable either battery aileron servo Kraft system will fit extension have used aile ron servo convenience Install aile ron servo far forward wing possible help situation Set up control surfaces rudder moves about 3/4 inch either side elevators move 1/2 up forward stick 5/8 inch down back stick ailerons move 3/16 inch both ways Note elevator moves down causes nose come up plane climb So double check move transmitter stick airplane climb elevator trailing edge goes down remainder con trols work inaconventional manner flying off hard surfaces Rocket City brake nose gear helps immensely very easy install Connect work forward stick nose down pitch control Adjust nose gear length airplane sits level ground approxi mately same height off ground main gear position nose gear position like really slow down landing extend nose strut 1/2 1/4 inch Nats able land stop within 100 foot circle making screeching stop Flying Since unusual aircraft let share some solutions potential problems some warnings Since thrust line above wing application full power slow airspeed will push nose down airplane slow enough full elevator wont hold up Therefore bounce landing de cide go around bad approach smoothly apply about 1/2 power until airspeed builds up Remember ele vator less effective low airspeeds cause no prop-wash blows over sure fix route antenna wont go prop comes loose top fin prop could jerk loose near receiver causing drastic perhaps catastrophic loss range Check aileron linkage wing installed look through fuselage hatch removed make sure tank does interfere aileron opera tion ailerons jam air cooly throttle back say Sayonara After some rough ground handling started get ting some flutter vertical fin high speed found fuselage worked loose top firewall piece 1/8 balsa glued fin opening above fuel tank cured would also advise against trying spins snap-rollsyou may recover airplane except pieces airplane will spin snap normal maneuvering 7Fox Fuel Line Models Life Blood Passes Through Simple Piece Fuel Line Surely Want Best As engine manufacturers acutely aware large portion called engine problems reality fuel line problems Symptoms fuel line trouble going lean air leaks speed fluctuations inability get rich enough high speed restricted flow Fox Fuel Lines best materials available physical proper ties selected model use Fox Fuel Lines worlds finest Tuft Line Silicone far strongest market semitransparent shows bubbles line heat resis tant Like silicone tubing tends slip off fittings unless care taken Neoprene Actually complex compound much elastic clings fittings main disadvan tage transparent Surgical Tubing Pure Rubber Very flexible Use sharp bends necessary Semi-transparent Shows bubbles line Holds fittings well Main disadvantage tends deteriorate rapidly silicone neoprene Plastic good anybodys dont think much plastic fuel line Advantage low price transparency Disadvantage tends collapse bends hardens age heat Tends leak air fittings after ITEM FUEL LINEPRICEITEM FUEL LINEPRICE 86880 Small Neoprene2 P8g.5086885 Small Clear Plautic2 P8g.25 86881 Medium Neoprene2 P8g.6086886 Medium Clear Plautic21/2 P8g.30 86882 Large Neoprene2 P8g.7086887 Large Clear Plautic2 P8g.40 86883 Small Tuff Line1 Pkg . 5586888 Small Surgical Tubing2 Pkg.50 86884 Medium Tufi Line1 P8g7086880 Med Surgical Tubing2 P8g.50 86851 Large Tuff Line1 Pkg16086890 Large Surgical Tubing2 P8g.60 FOX MANUFACTURING Fox Model Airplane Products 5305 Towson Smith Arkansas 72901 e 501-646-1656 control movements CG range recommended goof something up force spin best mode recovery full throttle help lower nose full down control ro tation stops throttle back gently pull out sufficient altitude remains last warning change basic aerody namic layout like putting fin front doubling size canard changes required CG position sta bility Most modelers dont know good rules thumb applicable canard air planes Lest end pessimistic note have very enjoyable time flying Zonker 40 investigating things will will making little improvements unusual looking ship freak oddity draws spectators highly maneuverable aero dynamically sound has first place trophy Novice Pattern 5th contest have ever entered Two Zonker 40s up same time really add excitement air show Anybody passing through Dayton Ohio area feel free stop demo flight build design would like hear experiences including problems have questions feel free write author 1250 Adams Street Fairborn Ohio 45324 Good luck Zonker 40 March 1977 81