SEASThIJTZ SINCE THIS design developed Ted Straders Strutz-Echo 1967 Wilson seaplane tradition chose Seastrutz its name proved fine flying easily built biplane does great job land sea basic construction built-up balsa straight forward formida ble problem biplane construction cabane struts simplified building jig makes part project snap Good flying characteristics Strutz Echo preserved hopefully im proved following modifications Bottom wing lengthened six inches insure enough area handle added weight floats Total wing area about 515 sq about effective 440 sq multiplied biplane efficiency fac tor 85% Weight tail minimized using covered framework tail surfaces turtleback Flying weight dry 3 pounds Iandplane 4 pounds sea plane Covering nylon over light Silkspan open areas heavy Silkspan over sheet wood except nylon-covered float bottoms Wing loading 196 oz/sq ft landplane 224 oz seaplane 19 ample power As landplane normal three-channel maneuvers performed ease As seaplane loops snap rolls etc possible Seaplane performance realistic takeoffs easy water-handling good Interchangeable water rudder tail wheel fixtures provided Front land ing gear struts lengthened prop clearance water flying wider tracking land Fuselage redesigned use servo tray provide mounting rear float struts inverted building over top view plan Fuselage waterproofed sheeting over opening above lower wing using Nyrod equivalent pushrods gasketing removable front hatch Floats subrudder/water rudder assembly new additions Authors high-step design used flat float bottoms proved other recent seaplanes experience model seaplanes observation full-size seaplanes small distance required between tip step afterbottom step itself can slight still perform its function However height float step tip step top float must great Also rear end float must high enough allow model rotate nose up make angle-of-attack wing least 8o12o too much high-step float bottom allows model rock rotate backward float tip allows maximum lift wings take off step minimizes water drag helping model gain speed water As model rises step wetted area becomes less 16 Model Aviation Next Statue Liberty pose favorite author-model picture Cape Cod author poses landplane version Seastrutz bipe simpleand functional Opposite page floats big enough float modal easilythe first rule float design Above Coming up step Steering good water speeds White circle side medicine bottle cap over charging plug Right Running step touch up elevator airborne holding down model will plane fiat bottoms high speed wish get back quickly beach Developed popular Strutz Echo Ted Strader 19-powered biplane REM controls delight fly land water U George Wilson water drag decreases Bottom float behind step should completely out water during run Construction Instructions assume reader novice step-by-step detail given Construction straight forward sim ple Cabane strut system devised Stra der strong easily constructed recommended jig used assemble struts am partial aliphatic-type glues such Titebond model properly water proofed dry surface immediate ly wet accidentally will have no problem glues avoid white glues Fuselage Bottom built first Cut out main side pieces add plywood doublers p doubler Cut out assem ble bulkheads except firewall sides upside down over plan Dont add bulkhead doublers K L until install front gear struts Firewall motor bearers installed after bottom part removed building board Build hatch sepa rate piece fit neatly bottom part Hatch starts its bottom plate Cut Vs narrower fuselage sides sand edges match slant bulkheads Make cut-out fit fuel tank use Add hatch bulkheads Install side sheeting top sheeting Turtle back cemented directly onto bot tom section Install bulkheads first add stringers filler pieces Double cover section Silkspan Install guide tubes pushrods Dope inside fuselage before adding bottom rear sheet ing Dope inside bottom sheeting before installation Install front gear struts doublers K L before installing front bottom sheeting Add sheeting over lower wing opening after servo tray installed Front hatch water-proofed 1/8 X 3/16 foam rubber gasket attached Pliobond bottom section around outer edges hatch Hatch held down four 2-56 machine screws blind nuts Sufficient pressure required assure tight fit Scuba diving shops may have good fuel-proof foam rubber sheeting Triangular doublers behind cockpit installed before plywood bottom sheeting rear float strut mounting sheeting has blind nuts rear strut screws installed before cementing place Blind nuts tail wheel/sub-rudder installed before bottom sheeting tail cemented place Tailwheel/Suh-Rudder These assemblies built very hard balsa base plates strength minimize crushing holddown screws Use washers under bolt heads help spread load Sections dowels short lengths tubing inset places take pressure screws Hinge tubes 1/16 ID nylon sewn epox ied place Use thin monofilament fish line reinforcing joints figure-8 hinges Floats Construction similar used fuselage Assemble sides bottoms bulkheads over set lines drawn separate sheet Add bottom sheeting fore removing basic assemblies build ing board Remove board add top bulkheads Dope inside floats inside sheeting used cover float tops Add upper side sheeting upper top sheet ing Cut pine blocks strut mounts care fully install blind nuts Mark locations strut stops pencil Dope bottoms install floats Trim bottoms upper side sheeting using razor plane sandpaper Install shape nose blocks Install triangular stops struts Angle floats respect thrust line overly critical prefer degree two negative angle top-of-float thrust line minimize air drag increase maximum takeoff rotation angle Float angle set bending rear struts slight ly less angle between rear strut legs will change angle neatly Inter-float strut spruce hard pine sanded streamlined shape between floats Ends fit snugly between stops float tops Tail Surfaces parts including sub-rudder built 3/16 sheet strip Use light good-quality wood minimum weight anti-warping Center member stabilizer rear upright sub-rudder medium hard strength January 1978 17 air Seastrutz realistic yet agile enough loop roll its 19 engine nI1TI-- i III rII~--I iEEtzic ~__- ILii i IIN/N ANTTTTSXXL -F II IIIIWIIIGSTTON lAIN BALSA--1I IiIIISATUNLESSSOTSTii IFNAAE7IAANANAWIWISYTTAL SO/N BASS LA WI vW~iirTIT----ySTl1I1rIi III r III III I I ZiF-~Iz.LSNYBNBYAN XBTWIAN ONIflBEXWI TB/NIiIA BA WINO 6/ABLA B AT AlA N/NO AlASEE TEXTLISA B/SNAB r OLITTASEXXLOX TIt Y--rkLA XXIII1II1NBXEIXBB Y-A-- BNYTET/ILAAANASOWITSAABXS I/BANG /10OSNLYXA/BBliiIIABASTIBOSALNE STATBASONBTLONAXLAANN NON/NA TTXTOA-BA BAITS/A- B IIN-tNXBNLSFUSELAGE ANN FLOATS FROAXN BLISS BATS IA WIOG/WIBSIX BATSI/N BALSA SAT UNLESS NOTES EBB SAL WIN I/N SAT IN XL 14I1~~~ AlBSBIA I BA BAIii I1 NSBAISASASWIFTBTFNNBSI1 SNISATI BASIS5 LB BAtlBSIIINNNT N BAN T/BA/AX/TLXNNA5 LBI/B AXTABAXONS rAOTIGSAAL ISTSUTX FETAl ST TED STNAOEN eNSEAPLANE UPDATE BY XTOTOE WILSON STRU TZ FULL-SIZE PLANS AVAILABLE Note plywood side pieces inset lower extreme rudder absorb beating tailwheel water-rudder control links Original model used nylon monofilament figure-8 stitches SEEPAGE 104 Wings Both wings built over plan Build dihedral brace first panel wing Join two halves before top sheeting added Order assembly follows Pin down bottom sheeting Cement dihe dral brace spar Position spar install ribs pinning place until glue dry Angle center rib match dihedral Install leading edge Install 3/8 sheeting center top wing Remove first panel Cabane Strut jig shown place top fuselage simplifies construction strut assembly insures accurate alignment Plywood used liberally doublers gear mounting Quarters used balance picture Note hatch holddown blind nuts 18 Model Aviation I- I K III SNEEr USLOBS BOrONI BtBmPU~ 1 IrOOU--OBOWN Br ocosor WILSONIS NOV IBiS lOVES 0050W IHOBYOLL board build second panel using same order assembly First panel blocked up dihedral angle sec ond panel being built Washout built wings top sheeting being installed Pin leading edge center rib panel build ing board Block up rear wing tip amount washout shown plan pin place Block trailing edge up two three other places between tip center making straight line center-to-tip Install leading edge sheeting center sheeting trailing edge sheeting Amount washout overly critical Just make sure both sides have equal amounts washout Model stable slow speeds has no tendency snap-roll Tip blocks installed after have rough shaped Trim sand after place Cabane Struts Until cabane strut jig came mind dubious about building bi plane Vertical wooden struts used model designs solve problem prac tical pretty manner Jig built material must accurate provides places rest tips wing supports being attached struts done struts position fuselage jig resting atop part fuselage normally under hatch First build jig Cement stops center fuselage simplify positioning building struts Next bend approximate shape two U-shaped pieces 1/8 music wire two 1/16 music wire tie struts Cut two 1/8 mw wing supports length Using rubberbands soft wire #16 18 solid copper mount wing supports jig fit U-shaped pieces Rebend necessary fit neatly slot through fuselage reason able fit wing support satisfied fit bind ends wing supports using thin copper wire apply flux solder Before second U strut remove partially made assembly jig slip piece silicone rubber tubing over center part wing supports makes soft non-slip mount wing Push tubing far can toward solder joints Fit attach second U-shaped piece Tie struts fitted bound fluxed soldered Finished strut assembly slips off jig little difficulty Strut assembly mounted fuselage using nylon monofilament line epoxy produces well-aligned top wing mount Finishing Insides structures sealed dope thinned epoxy Hobby poxy Formula 2 diluted l-to-l thin ner 90% isopropyl alcohol good sealer Seal inside pieces used close structure model finished using Silkspan over wood except float bottoms nylon covered Open areas covered light Silkspan nylon Heatshrink materials easy waterproof Flying Seastrutz didnt quite fly right-offdrawing-board planned engine check bit taxiing Bob Martin Bruce Selig made bids test fly Weath er good wind steady 10 mph Takeoff required ten feet climb-out dramatic Bob fed full down trim wished Except too much climb ballooning glide first flight great success Bruce verified Bobs findings its first two flights Seastrutz its landplane configuration did rudderelevator maneuvers Bob Bruce could think including inverted flight agreed increased rudder area would useful least 1/8 down trim stabilizer necessary Slow speed flight steady no unexpected snaps next day Ed McCarty flew water tests Wind least 20 mph gusts found place shielded hills Seastrutz steered well water must going enjoy seaplane fly ing got up step ease Although lake deceptively calm trees blowing hill top As usual caution thrown winds theorized float dragwould offset down-trim required land flying set elevator trim zero Takeoff dramatic After 75 feet Continued page 86 January1978 19 Float attachments pine hardwood Left shows pine blocks blind nuts place Hardwood stops right installed after pine blocks have sanded match contours floats Finished cabane struts Fuel tubing pieces installed during assembly provide soft bed wing Struts sewed bulkheads monofila ment epoxied Allows wide tolerance making necessary bendsordinarily problem bending heavy music wire SPECIAL PRO SERIES 2 FOR RC-FREE FLIGHT CONTROL LINE CIAPITCHPRICE 5%3489 63489 733%4119 53%456129 94566% 77%139 10467149 1066V 8W149 to6016159 114677% 7Y, 7%8159 it6E1W169 11%67169 126179 12555179 1356219 1496249 1566309 164%6389 W 55106 BLADE 855 EXTRA WIDE SERIES 400 B Poe SPEED & RACING ADVANCED DESIGN NO 1 IN PYLON RACING LEADING SPEED REGGRO HOLDER OF ALL TIMES RC PYLON RACING DIA PITCHPRICE 6%3%4129 755%6149 7SN 5/N 6N149 8%6% 6% 7 7%7%189 96%7 7A7%189 CONTROL LINE SPEED& RACING CIA PITCHPRICE 4/8A7129 4%55%129 6788%149 7 7%10%11169 889189 89N9%N189 8% 77%189 912 13219 51ARRflW Homebuilts Bill Youmans firstplace win Masters Class Greenville NRCHA Nationals last August seems increasing interest homebuilt helicopters won scratchbuilt own design composite components Bill came within 10 points aceing hover course local flier Norm Holland has developed scratchbuilt using Kavan mechanics tn-cycle landing gear Rev-o-lution canopy Futaba Sl5M ball-bearing servos EK single-stick radio Kraft engine Tach-Tron gover nor weight 12 1/2 pounds very smooth precise enough people inter ested could soon put kit form Look column further details Dual Counter Rotating Head ScratchBuilt Gilbert Laforest Montreal suc cessfully flew counter rotating-head heli copter own design Greenville NRCHA Nats Webra Speed 60 driving both heads unbelievably complicated pushrod system Self-designed transmitter two single sticks dual rudder knobs much Separate collective control head well separate cyclic control Tremendous under taking say nothing about getting mind synchronized hands Radio custom Can-Air Canadian ProLine some radio interference problems Next months column will cover unique finish helicopters first part building Aerospatiale SA-34 1 G Gazelle ducted fan-tail rotor youre flying youre trying hard enough Walt Schoonard 2080 Sharon Rd Winter Park FL 32789 Letters continued page 7 quality Model viation money best model aviation magazine field William R Barr AMA 31415 Claremont CA MA policy publish types models eventually shall get around Mr Barrs suggestions Mistaken Identity No doubt have received few letters already rare event havent would like point out photograph lower right hand corner page 25 Aug 1977 issue Model viation incorrectly captioned gentleman photo Rick Pear son winner last years Soar Nats well other contests sailplane holding Paragon Rick did outstanding job flying under less ideal conditions would shame did receive credit display flying skill Since generally true least 75% sailplanes performance direct function pilots skill would follow mention sailplane used would significant have no doubt uninten tional error know would want errors called attention proper caption can used Ed Slobod Pierce Aero Company Nonthridge CA Size It/Powers continued page 13 ing slower speed reduce somewhat power requirements because scaling down proto type its weight-empty condition rather its gross-weight condition thats ut Size Questions comments may ad dressed Bradford W Powers care magazine Seastrutz/Wi son continued page 18 full throttle some down-elevator Ed pulled up Seastrutz oil like scared duck full stall attitude 50 feet hit wind blowing toward hill blown end-over-end trees Damage minor Test flying continued next week Fall Brimfield meet time stabilizer shim under its leading edge rudder area doubled Seastrutz flew beautifully Among its test pilots Ted Straders son Eric testified flew very much like its predecessor Strutz Echo Seastrutz built mci dences shown will perform very well relatively docile its 46-in wing span compact biplane configuration felt might too quick average flier case diffi cult machine fly land water Have fun Radio Technique/Myers continued page 14 An ammeter measure charging discharging operating currents turntable drum-type chart feed measure servo transmit time shaker find intermittent prob lems heat lamp can Freezit similar chiller locate temperature-sensitive compon ents Special tools various types like desoldering irons Youve seen lot items listed under additional advertisements probability should leave will describe some simple non destructive tests should perform 86 Model Aviation NEWS FLASH Bob Smith Chatsworth CA set new World Speed Record June 19 Pylon mula 11125 RevUp 8%-6% new Pylon RaC ing prop OUT- PERFORMS ALL OTHERS AT THE 1976 NATIONALS 1st RC Masters Class 1st RC Advanced 1st RC Novice 1st RC Sport Scale 1st Formula Pylon 1st Quarter Midget Pylon 1st CL Stunt Open 1st CL Stunt Senior 1st CL Stunt Junior 1st CL Combat O & Sr 1st CL Slow Comb OP & Sr 1st CL Class 0 Speed Open 1st CL Class C Speed Jr & Sr 1st CLCIassB Speed Op & Sr 1st CL Cl Speed Op Sr Jr 1st FE Class B Open 1st FE Class C Open HIGH PERFORMANCE * COMPETITION PROVEN * THIN RIGID BLADES OP HARD MAPLE WOOD * SUPERBLY FINISHED COMPLETELY FUEL PIDOF 1st CL Carrier II Op Jr Sr 1st CL Carrier Jr & Sr 1st CL Formula 40 Opec 1st CL Class 6 Proto Jr
Edition: Model Aviation - 1978/01
Page Numbers: 16, 17, 18, 19, 86
SEASThIJTZ SINCE THIS design developed Ted Straders Strutz-Echo 1967 Wilson seaplane tradition chose Seastrutz its name proved fine flying easily built biplane does great job land sea basic construction built-up balsa straight forward formida ble problem biplane construction cabane struts simplified building jig makes part project snap Good flying characteristics Strutz Echo preserved hopefully im proved following modifications Bottom wing lengthened six inches insure enough area handle added weight floats Total wing area about 515 sq about effective 440 sq multiplied biplane efficiency fac tor 85% Weight tail minimized using covered framework tail surfaces turtleback Flying weight dry 3 pounds Iandplane 4 pounds sea plane Covering nylon over light Silkspan open areas heavy Silkspan over sheet wood except nylon-covered float bottoms Wing loading 196 oz/sq ft landplane 224 oz seaplane 19 ample power As landplane normal three-channel maneuvers performed ease As seaplane loops snap rolls etc possible Seaplane performance realistic takeoffs easy water-handling good Interchangeable water rudder tail wheel fixtures provided Front land ing gear struts lengthened prop clearance water flying wider tracking land Fuselage redesigned use servo tray provide mounting rear float struts inverted building over top view plan Fuselage waterproofed sheeting over opening above lower wing using Nyrod equivalent pushrods gasketing removable front hatch Floats subrudder/water rudder assembly new additions Authors high-step design used flat float bottoms proved other recent seaplanes experience model seaplanes observation full-size seaplanes small distance required between tip step afterbottom step itself can slight still perform its function However height float step tip step top float must great Also rear end float must high enough allow model rotate nose up make angle-of-attack wing least 8o12o too much high-step float bottom allows model rock rotate backward float tip allows maximum lift wings take off step minimizes water drag helping model gain speed water As model rises step wetted area becomes less 16 Model Aviation Next Statue Liberty pose favorite author-model picture Cape Cod author poses landplane version Seastrutz bipe simpleand functional Opposite page floats big enough float modal easilythe first rule float design Above Coming up step Steering good water speeds White circle side medicine bottle cap over charging plug Right Running step touch up elevator airborne holding down model will plane fiat bottoms high speed wish get back quickly beach Developed popular Strutz Echo Ted Strader 19-powered biplane REM controls delight fly land water U George Wilson water drag decreases Bottom float behind step should completely out water during run Construction Instructions assume reader novice step-by-step detail given Construction straight forward sim ple Cabane strut system devised Stra der strong easily constructed recommended jig used assemble struts am partial aliphatic-type glues such Titebond model properly water proofed dry surface immediate ly wet accidentally will have no problem glues avoid white glues Fuselage Bottom built first Cut out main side pieces add plywood doublers p doubler Cut out assem ble bulkheads except firewall sides upside down over plan Dont add bulkhead doublers K L until install front gear struts Firewall motor bearers installed after bottom part removed building board Build hatch sepa rate piece fit neatly bottom part Hatch starts its bottom plate Cut Vs narrower fuselage sides sand edges match slant bulkheads Make cut-out fit fuel tank use Add hatch bulkheads Install side sheeting top sheeting Turtle back cemented directly onto bot tom section Install bulkheads first add stringers filler pieces Double cover section Silkspan Install guide tubes pushrods Dope inside fuselage before adding bottom rear sheet ing Dope inside bottom sheeting before installation Install front gear struts doublers K L before installing front bottom sheeting Add sheeting over lower wing opening after servo tray installed Front hatch water-proofed 1/8 X 3/16 foam rubber gasket attached Pliobond bottom section around outer edges hatch Hatch held down four 2-56 machine screws blind nuts Sufficient pressure required assure tight fit Scuba diving shops may have good fuel-proof foam rubber sheeting Triangular doublers behind cockpit installed before plywood bottom sheeting rear float strut mounting sheeting has blind nuts rear strut screws installed before cementing place Blind nuts tail wheel/sub-rudder installed before bottom sheeting tail cemented place Tailwheel/Suh-Rudder These assemblies built very hard balsa base plates strength minimize crushing holddown screws Use washers under bolt heads help spread load Sections dowels short lengths tubing inset places take pressure screws Hinge tubes 1/16 ID nylon sewn epox ied place Use thin monofilament fish line reinforcing joints figure-8 hinges Floats Construction similar used fuselage Assemble sides bottoms bulkheads over set lines drawn separate sheet Add bottom sheeting fore removing basic assemblies build ing board Remove board add top bulkheads Dope inside floats inside sheeting used cover float tops Add upper side sheeting upper top sheet ing Cut pine blocks strut mounts care fully install blind nuts Mark locations strut stops pencil Dope bottoms install floats Trim bottoms upper side sheeting using razor plane sandpaper Install shape nose blocks Install triangular stops struts Angle floats respect thrust line overly critical prefer degree two negative angle top-of-float thrust line minimize air drag increase maximum takeoff rotation angle Float angle set bending rear struts slight ly less angle between rear strut legs will change angle neatly Inter-float strut spruce hard pine sanded streamlined shape between floats Ends fit snugly between stops float tops Tail Surfaces parts including sub-rudder built 3/16 sheet strip Use light good-quality wood minimum weight anti-warping Center member stabilizer rear upright sub-rudder medium hard strength January 1978 17 air Seastrutz realistic yet agile enough loop roll its 19 engine nI1TI-- i III rII~--I iEEtzic ~__- ILii i IIN/N ANTTTTSXXL -F II IIIIWIIIGSTTON lAIN BALSA--1I IiIIISATUNLESSSOTSTii IFNAAE7IAANANAWIWISYTTAL SO/N BASS LA WI vW~iirTIT----ySTl1I1rIi III r III III I I ZiF-~Iz.LSNYBNBYAN XBTWIAN ONIflBEXWI TB/NIiIA BA WINO 6/ABLA B AT AlA N/NO AlASEE TEXTLISA B/SNAB r OLITTASEXXLOX TIt Y--rkLA XXIII1II1NBXEIXBB Y-A-- BNYTET/ILAAANASOWITSAABXS I/BANG /10OSNLYXA/BBliiIIABASTIBOSALNE STATBASONBTLONAXLAANN NON/NA TTXTOA-BA BAITS/A- B IIN-tNXBNLSFUSELAGE ANN FLOATS FROAXN BLISS BATS IA WIOG/WIBSIX BATSI/N BALSA SAT UNLESS NOTES EBB SAL WIN I/N SAT IN XL 14I1~~~ AlBSBIA I BA BAIii I1 NSBAISASASWIFTBTFNNBSI1 SNISATI BASIS5 LB BAtlBSIIINNNT N BAN T/BA/AX/TLXNNA5 LBI/B AXTABAXONS rAOTIGSAAL ISTSUTX FETAl ST TED STNAOEN eNSEAPLANE UPDATE BY XTOTOE WILSON STRU TZ FULL-SIZE PLANS AVAILABLE Note plywood side pieces inset lower extreme rudder absorb beating tailwheel water-rudder control links Original model used nylon monofilament figure-8 stitches SEEPAGE 104 Wings Both wings built over plan Build dihedral brace first panel wing Join two halves before top sheeting added Order assembly follows Pin down bottom sheeting Cement dihe dral brace spar Position spar install ribs pinning place until glue dry Angle center rib match dihedral Install leading edge Install 3/8 sheeting center top wing Remove first panel Cabane Strut jig shown place top fuselage simplifies construction strut assembly insures accurate alignment Plywood used liberally doublers gear mounting Quarters used balance picture Note hatch holddown blind nuts 18 Model Aviation I- I K III SNEEr USLOBS BOrONI BtBmPU~ 1 IrOOU--OBOWN Br ocosor WILSONIS NOV IBiS lOVES 0050W IHOBYOLL board build second panel using same order assembly First panel blocked up dihedral angle sec ond panel being built Washout built wings top sheeting being installed Pin leading edge center rib panel build ing board Block up rear wing tip amount washout shown plan pin place Block trailing edge up two three other places between tip center making straight line center-to-tip Install leading edge sheeting center sheeting trailing edge sheeting Amount washout overly critical Just make sure both sides have equal amounts washout Model stable slow speeds has no tendency snap-roll Tip blocks installed after have rough shaped Trim sand after place Cabane Struts Until cabane strut jig came mind dubious about building bi plane Vertical wooden struts used model designs solve problem prac tical pretty manner Jig built material must accurate provides places rest tips wing supports being attached struts done struts position fuselage jig resting atop part fuselage normally under hatch First build jig Cement stops center fuselage simplify positioning building struts Next bend approximate shape two U-shaped pieces 1/8 music wire two 1/16 music wire tie struts Cut two 1/8 mw wing supports length Using rubberbands soft wire #16 18 solid copper mount wing supports jig fit U-shaped pieces Rebend necessary fit neatly slot through fuselage reason able fit wing support satisfied fit bind ends wing supports using thin copper wire apply flux solder Before second U strut remove partially made assembly jig slip piece silicone rubber tubing over center part wing supports makes soft non-slip mount wing Push tubing far can toward solder joints Fit attach second U-shaped piece Tie struts fitted bound fluxed soldered Finished strut assembly slips off jig little difficulty Strut assembly mounted fuselage using nylon monofilament line epoxy produces well-aligned top wing mount Finishing Insides structures sealed dope thinned epoxy Hobby poxy Formula 2 diluted l-to-l thin ner 90% isopropyl alcohol good sealer Seal inside pieces used close structure model finished using Silkspan over wood except float bottoms nylon covered Open areas covered light Silkspan nylon Heatshrink materials easy waterproof Flying Seastrutz didnt quite fly right-offdrawing-board planned engine check bit taxiing Bob Martin Bruce Selig made bids test fly Weath er good wind steady 10 mph Takeoff required ten feet climb-out dramatic Bob fed full down trim wished Except too much climb ballooning glide first flight great success Bruce verified Bobs findings its first two flights Seastrutz its landplane configuration did rudderelevator maneuvers Bob Bruce could think including inverted flight agreed increased rudder area would useful least 1/8 down trim stabilizer necessary Slow speed flight steady no unexpected snaps next day Ed McCarty flew water tests Wind least 20 mph gusts found place shielded hills Seastrutz steered well water must going enjoy seaplane fly ing got up step ease Although lake deceptively calm trees blowing hill top As usual caution thrown winds theorized float dragwould offset down-trim required land flying set elevator trim zero Takeoff dramatic After 75 feet Continued page 86 January1978 19 Float attachments pine hardwood Left shows pine blocks blind nuts place Hardwood stops right installed after pine blocks have sanded match contours floats Finished cabane struts Fuel tubing pieces installed during assembly provide soft bed wing Struts sewed bulkheads monofila ment epoxied Allows wide tolerance making necessary bendsordinarily problem bending heavy music wire SPECIAL PRO SERIES 2 FOR RC-FREE FLIGHT CONTROL LINE CIAPITCHPRICE 5%3489 63489 733%4119 53%456129 94566% 77%139 10467149 1066V 8W149 to6016159 114677% 7Y, 7%8159 it6E1W169 11%67169 126179 12555179 1356219 1496249 1566309 164%6389 W 55106 BLADE 855 EXTRA WIDE SERIES 400 B Poe SPEED & RACING ADVANCED DESIGN NO 1 IN PYLON RACING LEADING SPEED REGGRO HOLDER OF ALL TIMES RC PYLON RACING DIA PITCHPRICE 6%3%4129 755%6149 7SN 5/N 6N149 8%6% 6% 7 7%7%189 96%7 7A7%189 CONTROL LINE SPEED& RACING CIA PITCHPRICE 4/8A7129 4%55%129 6788%149 7 7%10%11169 889189 89N9%N189 8% 77%189 912 13219 51ARRflW Homebuilts Bill Youmans firstplace win Masters Class Greenville NRCHA Nationals last August seems increasing interest homebuilt helicopters won scratchbuilt own design composite components Bill came within 10 points aceing hover course local flier Norm Holland has developed scratchbuilt using Kavan mechanics tn-cycle landing gear Rev-o-lution canopy Futaba Sl5M ball-bearing servos EK single-stick radio Kraft engine Tach-Tron gover nor weight 12 1/2 pounds very smooth precise enough people inter ested could soon put kit form Look column further details Dual Counter Rotating Head ScratchBuilt Gilbert Laforest Montreal suc cessfully flew counter rotating-head heli copter own design Greenville NRCHA Nats Webra Speed 60 driving both heads unbelievably complicated pushrod system Self-designed transmitter two single sticks dual rudder knobs much Separate collective control head well separate cyclic control Tremendous under taking say nothing about getting mind synchronized hands Radio custom Can-Air Canadian ProLine some radio interference problems Next months column will cover unique finish helicopters first part building Aerospatiale SA-34 1 G Gazelle ducted fan-tail rotor youre flying youre trying hard enough Walt Schoonard 2080 Sharon Rd Winter Park FL 32789 Letters continued page 7 quality Model viation money best model aviation magazine field William R Barr AMA 31415 Claremont CA MA policy publish types models eventually shall get around Mr Barrs suggestions Mistaken Identity No doubt have received few letters already rare event havent would like point out photograph lower right hand corner page 25 Aug 1977 issue Model viation incorrectly captioned gentleman photo Rick Pear son winner last years Soar Nats well other contests sailplane holding Paragon Rick did outstanding job flying under less ideal conditions would shame did receive credit display flying skill Since generally true least 75% sailplanes performance direct function pilots skill would follow mention sailplane used would significant have no doubt uninten tional error know would want errors called attention proper caption can used Ed Slobod Pierce Aero Company Nonthridge CA Size It/Powers continued page 13 ing slower speed reduce somewhat power requirements because scaling down proto type its weight-empty condition rather its gross-weight condition thats ut Size Questions comments may ad dressed Bradford W Powers care magazine Seastrutz/Wi son continued page 18 full throttle some down-elevator Ed pulled up Seastrutz oil like scared duck full stall attitude 50 feet hit wind blowing toward hill blown end-over-end trees Damage minor Test flying continued next week Fall Brimfield meet time stabilizer shim under its leading edge rudder area doubled Seastrutz flew beautifully Among its test pilots Ted Straders son Eric testified flew very much like its predecessor Strutz Echo Seastrutz built mci dences shown will perform very well relatively docile its 46-in wing span compact biplane configuration felt might too quick average flier case diffi cult machine fly land water Have fun Radio Technique/Myers continued page 14 An ammeter measure charging discharging operating currents turntable drum-type chart feed measure servo transmit time shaker find intermittent prob lems heat lamp can Freezit similar chiller locate temperature-sensitive compon ents Special tools various types like desoldering irons Youve seen lot items listed under additional advertisements probability should leave will describe some simple non destructive tests should perform 86 Model Aviation NEWS FLASH Bob Smith Chatsworth CA set new World Speed Record June 19 Pylon mula 11125 RevUp 8%-6% new Pylon RaC ing prop OUT- PERFORMS ALL OTHERS AT THE 1976 NATIONALS 1st RC Masters Class 1st RC Advanced 1st RC Novice 1st RC Sport Scale 1st Formula Pylon 1st Quarter Midget Pylon 1st CL Stunt Open 1st CL Stunt Senior 1st CL Stunt Junior 1st CL Combat O & Sr 1st CL Slow Comb OP & Sr 1st CL Class 0 Speed Open 1st CL Class C Speed Jr & Sr 1st CLCIassB Speed Op & Sr 1st CL Cl Speed Op Sr Jr 1st FE Class B Open 1st FE Class C Open HIGH PERFORMANCE * COMPETITION PROVEN * THIN RIGID BLADES OP HARD MAPLE WOOD * SUPERBLY FINISHED COMPLETELY FUEL PIDOF 1st CL Carrier II Op Jr Sr 1st CL Carrier Jr & Sr 1st CL Formula 40 Opec 1st CL Class 6 Proto Jr
Edition: Model Aviation - 1978/01
Page Numbers: 16, 17, 18, 19, 86
SEASThIJTZ SINCE THIS design developed Ted Straders Strutz-Echo 1967 Wilson seaplane tradition chose Seastrutz its name proved fine flying easily built biplane does great job land sea basic construction built-up balsa straight forward formida ble problem biplane construction cabane struts simplified building jig makes part project snap Good flying characteristics Strutz Echo preserved hopefully im proved following modifications Bottom wing lengthened six inches insure enough area handle added weight floats Total wing area about 515 sq about effective 440 sq multiplied biplane efficiency fac tor 85% Weight tail minimized using covered framework tail surfaces turtleback Flying weight dry 3 pounds Iandplane 4 pounds sea plane Covering nylon over light Silkspan open areas heavy Silkspan over sheet wood except nylon-covered float bottoms Wing loading 196 oz/sq ft landplane 224 oz seaplane 19 ample power As landplane normal three-channel maneuvers performed ease As seaplane loops snap rolls etc possible Seaplane performance realistic takeoffs easy water-handling good Interchangeable water rudder tail wheel fixtures provided Front land ing gear struts lengthened prop clearance water flying wider tracking land Fuselage redesigned use servo tray provide mounting rear float struts inverted building over top view plan Fuselage waterproofed sheeting over opening above lower wing using Nyrod equivalent pushrods gasketing removable front hatch Floats subrudder/water rudder assembly new additions Authors high-step design used flat float bottoms proved other recent seaplanes experience model seaplanes observation full-size seaplanes small distance required between tip step afterbottom step itself can slight still perform its function However height float step tip step top float must great Also rear end float must high enough allow model rotate nose up make angle-of-attack wing least 8o12o too much high-step float bottom allows model rock rotate backward float tip allows maximum lift wings take off step minimizes water drag helping model gain speed water As model rises step wetted area becomes less 16 Model Aviation Next Statue Liberty pose favorite author-model picture Cape Cod author poses landplane version Seastrutz bipe simpleand functional Opposite page floats big enough float modal easilythe first rule float design Above Coming up step Steering good water speeds White circle side medicine bottle cap over charging plug Right Running step touch up elevator airborne holding down model will plane fiat bottoms high speed wish get back quickly beach Developed popular Strutz Echo Ted Strader 19-powered biplane REM controls delight fly land water U George Wilson water drag decreases Bottom float behind step should completely out water during run Construction Instructions assume reader novice step-by-step detail given Construction straight forward sim ple Cabane strut system devised Stra der strong easily constructed recommended jig used assemble struts am partial aliphatic-type glues such Titebond model properly water proofed dry surface immediate ly wet accidentally will have no problem glues avoid white glues Fuselage Bottom built first Cut out main side pieces add plywood doublers p doubler Cut out assem ble bulkheads except firewall sides upside down over plan Dont add bulkhead doublers K L until install front gear struts Firewall motor bearers installed after bottom part removed building board Build hatch sepa rate piece fit neatly bottom part Hatch starts its bottom plate Cut Vs narrower fuselage sides sand edges match slant bulkheads Make cut-out fit fuel tank use Add hatch bulkheads Install side sheeting top sheeting Turtle back cemented directly onto bot tom section Install bulkheads first add stringers filler pieces Double cover section Silkspan Install guide tubes pushrods Dope inside fuselage before adding bottom rear sheet ing Dope inside bottom sheeting before installation Install front gear struts doublers K L before installing front bottom sheeting Add sheeting over lower wing opening after servo tray installed Front hatch water-proofed 1/8 X 3/16 foam rubber gasket attached Pliobond bottom section around outer edges hatch Hatch held down four 2-56 machine screws blind nuts Sufficient pressure required assure tight fit Scuba diving shops may have good fuel-proof foam rubber sheeting Triangular doublers behind cockpit installed before plywood bottom sheeting rear float strut mounting sheeting has blind nuts rear strut screws installed before cementing place Blind nuts tail wheel/sub-rudder installed before bottom sheeting tail cemented place Tailwheel/Suh-Rudder These assemblies built very hard balsa base plates strength minimize crushing holddown screws Use washers under bolt heads help spread load Sections dowels short lengths tubing inset places take pressure screws Hinge tubes 1/16 ID nylon sewn epox ied place Use thin monofilament fish line reinforcing joints figure-8 hinges Floats Construction similar used fuselage Assemble sides bottoms bulkheads over set lines drawn separate sheet Add bottom sheeting fore removing basic assemblies build ing board Remove board add top bulkheads Dope inside floats inside sheeting used cover float tops Add upper side sheeting upper top sheet ing Cut pine blocks strut mounts care fully install blind nuts Mark locations strut stops pencil Dope bottoms install floats Trim bottoms upper side sheeting using razor plane sandpaper Install shape nose blocks Install triangular stops struts Angle floats respect thrust line overly critical prefer degree two negative angle top-of-float thrust line minimize air drag increase maximum takeoff rotation angle Float angle set bending rear struts slight ly less angle between rear strut legs will change angle neatly Inter-float strut spruce hard pine sanded streamlined shape between floats Ends fit snugly between stops float tops Tail Surfaces parts including sub-rudder built 3/16 sheet strip Use light good-quality wood minimum weight anti-warping Center member stabilizer rear upright sub-rudder medium hard strength January 1978 17 air Seastrutz realistic yet agile enough loop roll its 19 engine nI1TI-- i III rII~--I iEEtzic ~__- ILii i IIN/N ANTTTTSXXL -F II IIIIWIIIGSTTON lAIN BALSA--1I IiIIISATUNLESSSOTSTii IFNAAE7IAANANAWIWISYTTAL SO/N BASS LA WI vW~iirTIT----ySTl1I1rIi III r III III I I ZiF-~Iz.LSNYBNBYAN XBTWIAN ONIflBEXWI TB/NIiIA BA WINO 6/ABLA B AT AlA N/NO AlASEE TEXTLISA B/SNAB r OLITTASEXXLOX TIt Y--rkLA XXIII1II1NBXEIXBB Y-A-- BNYTET/ILAAANASOWITSAABXS I/BANG /10OSNLYXA/BBliiIIABASTIBOSALNE STATBASONBTLONAXLAANN NON/NA TTXTOA-BA BAITS/A- B IIN-tNXBNLSFUSELAGE ANN FLOATS FROAXN BLISS BATS IA WIOG/WIBSIX BATSI/N BALSA SAT UNLESS NOTES EBB SAL WIN I/N SAT IN XL 14I1~~~ AlBSBIA I BA BAIii I1 NSBAISASASWIFTBTFNNBSI1 SNISATI BASIS5 LB BAtlBSIIINNNT N BAN T/BA/AX/TLXNNA5 LBI/B AXTABAXONS rAOTIGSAAL ISTSUTX FETAl ST TED STNAOEN eNSEAPLANE UPDATE BY XTOTOE WILSON STRU TZ FULL-SIZE PLANS AVAILABLE Note plywood side pieces inset lower extreme rudder absorb beating tailwheel water-rudder control links Original model used nylon monofilament figure-8 stitches SEEPAGE 104 Wings Both wings built over plan Build dihedral brace first panel wing Join two halves before top sheeting added Order assembly follows Pin down bottom sheeting Cement dihe dral brace spar Position spar install ribs pinning place until glue dry Angle center rib match dihedral Install leading edge Install 3/8 sheeting center top wing Remove first panel Cabane Strut jig shown place top fuselage simplifies construction strut assembly insures accurate alignment Plywood used liberally doublers gear mounting Quarters used balance picture Note hatch holddown blind nuts 18 Model Aviation I- I K III SNEEr USLOBS BOrONI BtBmPU~ 1 IrOOU--OBOWN Br ocosor WILSONIS NOV IBiS lOVES 0050W IHOBYOLL board build second panel using same order assembly First panel blocked up dihedral angle sec ond panel being built Washout built wings top sheeting being installed Pin leading edge center rib panel build ing board Block up rear wing tip amount washout shown plan pin place Block trailing edge up two three other places between tip center making straight line center-to-tip Install leading edge sheeting center sheeting trailing edge sheeting Amount washout overly critical Just make sure both sides have equal amounts washout Model stable slow speeds has no tendency snap-roll Tip blocks installed after have rough shaped Trim sand after place Cabane Struts Until cabane strut jig came mind dubious about building bi plane Vertical wooden struts used model designs solve problem prac tical pretty manner Jig built material must accurate provides places rest tips wing supports being attached struts done struts position fuselage jig resting atop part fuselage normally under hatch First build jig Cement stops center fuselage simplify positioning building struts Next bend approximate shape two U-shaped pieces 1/8 music wire two 1/16 music wire tie struts Cut two 1/8 mw wing supports length Using rubberbands soft wire #16 18 solid copper mount wing supports jig fit U-shaped pieces Rebend necessary fit neatly slot through fuselage reason able fit wing support satisfied fit bind ends wing supports using thin copper wire apply flux solder Before second U strut remove partially made assembly jig slip piece silicone rubber tubing over center part wing supports makes soft non-slip mount wing Push tubing far can toward solder joints Fit attach second U-shaped piece Tie struts fitted bound fluxed soldered Finished strut assembly slips off jig little difficulty Strut assembly mounted fuselage using nylon monofilament line epoxy produces well-aligned top wing mount Finishing Insides structures sealed dope thinned epoxy Hobby poxy Formula 2 diluted l-to-l thin ner 90% isopropyl alcohol good sealer Seal inside pieces used close structure model finished using Silkspan over wood except float bottoms nylon covered Open areas covered light Silkspan nylon Heatshrink materials easy waterproof Flying Seastrutz didnt quite fly right-offdrawing-board planned engine check bit taxiing Bob Martin Bruce Selig made bids test fly Weath er good wind steady 10 mph Takeoff required ten feet climb-out dramatic Bob fed full down trim wished Except too much climb ballooning glide first flight great success Bruce verified Bobs findings its first two flights Seastrutz its landplane configuration did rudderelevator maneuvers Bob Bruce could think including inverted flight agreed increased rudder area would useful least 1/8 down trim stabilizer necessary Slow speed flight steady no unexpected snaps next day Ed McCarty flew water tests Wind least 20 mph gusts found place shielded hills Seastrutz steered well water must going enjoy seaplane fly ing got up step ease Although lake deceptively calm trees blowing hill top As usual caution thrown winds theorized float dragwould offset down-trim required land flying set elevator trim zero Takeoff dramatic After 75 feet Continued page 86 January1978 19 Float attachments pine hardwood Left shows pine blocks blind nuts place Hardwood stops right installed after pine blocks have sanded match contours floats Finished cabane struts Fuel tubing pieces installed during assembly provide soft bed wing Struts sewed bulkheads monofila ment epoxied Allows wide tolerance making necessary bendsordinarily problem bending heavy music wire SPECIAL PRO SERIES 2 FOR RC-FREE FLIGHT CONTROL LINE CIAPITCHPRICE 5%3489 63489 733%4119 53%456129 94566% 77%139 10467149 1066V 8W149 to6016159 114677% 7Y, 7%8159 it6E1W169 11%67169 126179 12555179 1356219 1496249 1566309 164%6389 W 55106 BLADE 855 EXTRA WIDE SERIES 400 B Poe SPEED & RACING ADVANCED DESIGN NO 1 IN PYLON RACING LEADING SPEED REGGRO HOLDER OF ALL TIMES RC PYLON RACING DIA PITCHPRICE 6%3%4129 755%6149 7SN 5/N 6N149 8%6% 6% 7 7%7%189 96%7 7A7%189 CONTROL LINE SPEED& RACING CIA PITCHPRICE 4/8A7129 4%55%129 6788%149 7 7%10%11169 889189 89N9%N189 8% 77%189 912 13219 51ARRflW Homebuilts Bill Youmans firstplace win Masters Class Greenville NRCHA Nationals last August seems increasing interest homebuilt helicopters won scratchbuilt own design composite components Bill came within 10 points aceing hover course local flier Norm Holland has developed scratchbuilt using Kavan mechanics tn-cycle landing gear Rev-o-lution canopy Futaba Sl5M ball-bearing servos EK single-stick radio Kraft engine Tach-Tron gover nor weight 12 1/2 pounds very smooth precise enough people inter ested could soon put kit form Look column further details Dual Counter Rotating Head ScratchBuilt Gilbert Laforest Montreal suc cessfully flew counter rotating-head heli copter own design Greenville NRCHA Nats Webra Speed 60 driving both heads unbelievably complicated pushrod system Self-designed transmitter two single sticks dual rudder knobs much Separate collective control head well separate cyclic control Tremendous under taking say nothing about getting mind synchronized hands Radio custom Can-Air Canadian ProLine some radio interference problems Next months column will cover unique finish helicopters first part building Aerospatiale SA-34 1 G Gazelle ducted fan-tail rotor youre flying youre trying hard enough Walt Schoonard 2080 Sharon Rd Winter Park FL 32789 Letters continued page 7 quality Model viation money best model aviation magazine field William R Barr AMA 31415 Claremont CA MA policy publish types models eventually shall get around Mr Barrs suggestions Mistaken Identity No doubt have received few letters already rare event havent would like point out photograph lower right hand corner page 25 Aug 1977 issue Model viation incorrectly captioned gentleman photo Rick Pear son winner last years Soar Nats well other contests sailplane holding Paragon Rick did outstanding job flying under less ideal conditions would shame did receive credit display flying skill Since generally true least 75% sailplanes performance direct function pilots skill would follow mention sailplane used would significant have no doubt uninten tional error know would want errors called attention proper caption can used Ed Slobod Pierce Aero Company Nonthridge CA Size It/Powers continued page 13 ing slower speed reduce somewhat power requirements because scaling down proto type its weight-empty condition rather its gross-weight condition thats ut Size Questions comments may ad dressed Bradford W Powers care magazine Seastrutz/Wi son continued page 18 full throttle some down-elevator Ed pulled up Seastrutz oil like scared duck full stall attitude 50 feet hit wind blowing toward hill blown end-over-end trees Damage minor Test flying continued next week Fall Brimfield meet time stabilizer shim under its leading edge rudder area doubled Seastrutz flew beautifully Among its test pilots Ted Straders son Eric testified flew very much like its predecessor Strutz Echo Seastrutz built mci dences shown will perform very well relatively docile its 46-in wing span compact biplane configuration felt might too quick average flier case diffi cult machine fly land water Have fun Radio Technique/Myers continued page 14 An ammeter measure charging discharging operating currents turntable drum-type chart feed measure servo transmit time shaker find intermittent prob lems heat lamp can Freezit similar chiller locate temperature-sensitive compon ents Special tools various types like desoldering irons Youve seen lot items listed under additional advertisements probability should leave will describe some simple non destructive tests should perform 86 Model Aviation NEWS FLASH Bob Smith Chatsworth CA set new World Speed Record June 19 Pylon mula 11125 RevUp 8%-6% new Pylon RaC ing prop OUT- PERFORMS ALL OTHERS AT THE 1976 NATIONALS 1st RC Masters Class 1st RC Advanced 1st RC Novice 1st RC Sport Scale 1st Formula Pylon 1st Quarter Midget Pylon 1st CL Stunt Open 1st CL Stunt Senior 1st CL Stunt Junior 1st CL Combat O & Sr 1st CL Slow Comb OP & Sr 1st CL Class 0 Speed Open 1st CL Class C Speed Jr & Sr 1st CLCIassB Speed Op & Sr 1st CL Cl Speed Op Sr Jr 1st FE Class B Open 1st FE Class C Open HIGH PERFORMANCE * COMPETITION PROVEN * THIN RIGID BLADES OP HARD MAPLE WOOD * SUPERBLY FINISHED COMPLETELY FUEL PIDOF 1st CL Carrier II Op Jr Sr 1st CL Carrier Jr & Sr 1st CL Formula 40 Opec 1st CL Class 6 Proto Jr
Edition: Model Aviation - 1978/01
Page Numbers: 16, 17, 18, 19, 86
SEASThIJTZ SINCE THIS design developed Ted Straders Strutz-Echo 1967 Wilson seaplane tradition chose Seastrutz its name proved fine flying easily built biplane does great job land sea basic construction built-up balsa straight forward formida ble problem biplane construction cabane struts simplified building jig makes part project snap Good flying characteristics Strutz Echo preserved hopefully im proved following modifications Bottom wing lengthened six inches insure enough area handle added weight floats Total wing area about 515 sq about effective 440 sq multiplied biplane efficiency fac tor 85% Weight tail minimized using covered framework tail surfaces turtleback Flying weight dry 3 pounds Iandplane 4 pounds sea plane Covering nylon over light Silkspan open areas heavy Silkspan over sheet wood except nylon-covered float bottoms Wing loading 196 oz/sq ft landplane 224 oz seaplane 19 ample power As landplane normal three-channel maneuvers performed ease As seaplane loops snap rolls etc possible Seaplane performance realistic takeoffs easy water-handling good Interchangeable water rudder tail wheel fixtures provided Front land ing gear struts lengthened prop clearance water flying wider tracking land Fuselage redesigned use servo tray provide mounting rear float struts inverted building over top view plan Fuselage waterproofed sheeting over opening above lower wing using Nyrod equivalent pushrods gasketing removable front hatch Floats subrudder/water rudder assembly new additions Authors high-step design used flat float bottoms proved other recent seaplanes experience model seaplanes observation full-size seaplanes small distance required between tip step afterbottom step itself can slight still perform its function However height float step tip step top float must great Also rear end float must high enough allow model rotate nose up make angle-of-attack wing least 8o12o too much high-step float bottom allows model rock rotate backward float tip allows maximum lift wings take off step minimizes water drag helping model gain speed water As model rises step wetted area becomes less 16 Model Aviation Next Statue Liberty pose favorite author-model picture Cape Cod author poses landplane version Seastrutz bipe simpleand functional Opposite page floats big enough float modal easilythe first rule float design Above Coming up step Steering good water speeds White circle side medicine bottle cap over charging plug Right Running step touch up elevator airborne holding down model will plane fiat bottoms high speed wish get back quickly beach Developed popular Strutz Echo Ted Strader 19-powered biplane REM controls delight fly land water U George Wilson water drag decreases Bottom float behind step should completely out water during run Construction Instructions assume reader novice step-by-step detail given Construction straight forward sim ple Cabane strut system devised Stra der strong easily constructed recommended jig used assemble struts am partial aliphatic-type glues such Titebond model properly water proofed dry surface immediate ly wet accidentally will have no problem glues avoid white glues Fuselage Bottom built first Cut out main side pieces add plywood doublers p doubler Cut out assem ble bulkheads except firewall sides upside down over plan Dont add bulkhead doublers K L until install front gear struts Firewall motor bearers installed after bottom part removed building board Build hatch sepa rate piece fit neatly bottom part Hatch starts its bottom plate Cut Vs narrower fuselage sides sand edges match slant bulkheads Make cut-out fit fuel tank use Add hatch bulkheads Install side sheeting top sheeting Turtle back cemented directly onto bot tom section Install bulkheads first add stringers filler pieces Double cover section Silkspan Install guide tubes pushrods Dope inside fuselage before adding bottom rear sheet ing Dope inside bottom sheeting before installation Install front gear struts doublers K L before installing front bottom sheeting Add sheeting over lower wing opening after servo tray installed Front hatch water-proofed 1/8 X 3/16 foam rubber gasket attached Pliobond bottom section around outer edges hatch Hatch held down four 2-56 machine screws blind nuts Sufficient pressure required assure tight fit Scuba diving shops may have good fuel-proof foam rubber sheeting Triangular doublers behind cockpit installed before plywood bottom sheeting rear float strut mounting sheeting has blind nuts rear strut screws installed before cementing place Blind nuts tail wheel/sub-rudder installed before bottom sheeting tail cemented place Tailwheel/Suh-Rudder These assemblies built very hard balsa base plates strength minimize crushing holddown screws Use washers under bolt heads help spread load Sections dowels short lengths tubing inset places take pressure screws Hinge tubes 1/16 ID nylon sewn epox ied place Use thin monofilament fish line reinforcing joints figure-8 hinges Floats Construction similar used fuselage Assemble sides bottoms bulkheads over set lines drawn separate sheet Add bottom sheeting fore removing basic assemblies build ing board Remove board add top bulkheads Dope inside floats inside sheeting used cover float tops Add upper side sheeting upper top sheet ing Cut pine blocks strut mounts care fully install blind nuts Mark locations strut stops pencil Dope bottoms install floats Trim bottoms upper side sheeting using razor plane sandpaper Install shape nose blocks Install triangular stops struts Angle floats respect thrust line overly critical prefer degree two negative angle top-of-float thrust line minimize air drag increase maximum takeoff rotation angle Float angle set bending rear struts slight ly less angle between rear strut legs will change angle neatly Inter-float strut spruce hard pine sanded streamlined shape between floats Ends fit snugly between stops float tops Tail Surfaces parts including sub-rudder built 3/16 sheet strip Use light good-quality wood minimum weight anti-warping Center member stabilizer rear upright sub-rudder medium hard strength January 1978 17 air Seastrutz realistic yet agile enough loop roll its 19 engine nI1TI-- i III rII~--I iEEtzic ~__- ILii i IIN/N ANTTTTSXXL -F II IIIIWIIIGSTTON lAIN BALSA--1I IiIIISATUNLESSSOTSTii IFNAAE7IAANANAWIWISYTTAL SO/N BASS LA WI vW~iirTIT----ySTl1I1rIi III r III III I I ZiF-~Iz.LSNYBNBYAN XBTWIAN ONIflBEXWI TB/NIiIA BA WINO 6/ABLA B AT AlA N/NO AlASEE TEXTLISA B/SNAB r OLITTASEXXLOX TIt Y--rkLA XXIII1II1NBXEIXBB Y-A-- BNYTET/ILAAANASOWITSAABXS I/BANG /10OSNLYXA/BBliiIIABASTIBOSALNE STATBASONBTLONAXLAANN NON/NA TTXTOA-BA BAITS/A- B IIN-tNXBNLSFUSELAGE ANN FLOATS FROAXN BLISS BATS IA WIOG/WIBSIX BATSI/N BALSA SAT UNLESS NOTES EBB SAL WIN I/N SAT IN XL 14I1~~~ AlBSBIA I BA BAIii I1 NSBAISASASWIFTBTFNNBSI1 SNISATI BASIS5 LB BAtlBSIIINNNT N BAN T/BA/AX/TLXNNA5 LBI/B AXTABAXONS rAOTIGSAAL ISTSUTX FETAl ST TED STNAOEN eNSEAPLANE UPDATE BY XTOTOE WILSON STRU TZ FULL-SIZE PLANS AVAILABLE Note plywood side pieces inset lower extreme rudder absorb beating tailwheel water-rudder control links Original model used nylon monofilament figure-8 stitches SEEPAGE 104 Wings Both wings built over plan Build dihedral brace first panel wing Join two halves before top sheeting added Order assembly follows Pin down bottom sheeting Cement dihe dral brace spar Position spar install ribs pinning place until glue dry Angle center rib match dihedral Install leading edge Install 3/8 sheeting center top wing Remove first panel Cabane Strut jig shown place top fuselage simplifies construction strut assembly insures accurate alignment Plywood used liberally doublers gear mounting Quarters used balance picture Note hatch holddown blind nuts 18 Model Aviation I- I K III SNEEr USLOBS BOrONI BtBmPU~ 1 IrOOU--OBOWN Br ocosor WILSONIS NOV IBiS lOVES 0050W IHOBYOLL board build second panel using same order assembly First panel blocked up dihedral angle sec ond panel being built Washout built wings top sheeting being installed Pin leading edge center rib panel build ing board Block up rear wing tip amount washout shown plan pin place Block trailing edge up two three other places between tip center making straight line center-to-tip Install leading edge sheeting center sheeting trailing edge sheeting Amount washout overly critical Just make sure both sides have equal amounts washout Model stable slow speeds has no tendency snap-roll Tip blocks installed after have rough shaped Trim sand after place Cabane Struts Until cabane strut jig came mind dubious about building bi plane Vertical wooden struts used model designs solve problem prac tical pretty manner Jig built material must accurate provides places rest tips wing supports being attached struts done struts position fuselage jig resting atop part fuselage normally under hatch First build jig Cement stops center fuselage simplify positioning building struts Next bend approximate shape two U-shaped pieces 1/8 music wire two 1/16 music wire tie struts Cut two 1/8 mw wing supports length Using rubberbands soft wire #16 18 solid copper mount wing supports jig fit U-shaped pieces Rebend necessary fit neatly slot through fuselage reason able fit wing support satisfied fit bind ends wing supports using thin copper wire apply flux solder Before second U strut remove partially made assembly jig slip piece silicone rubber tubing over center part wing supports makes soft non-slip mount wing Push tubing far can toward solder joints Fit attach second U-shaped piece Tie struts fitted bound fluxed soldered Finished strut assembly slips off jig little difficulty Strut assembly mounted fuselage using nylon monofilament line epoxy produces well-aligned top wing mount Finishing Insides structures sealed dope thinned epoxy Hobby poxy Formula 2 diluted l-to-l thin ner 90% isopropyl alcohol good sealer Seal inside pieces used close structure model finished using Silkspan over wood except float bottoms nylon covered Open areas covered light Silkspan nylon Heatshrink materials easy waterproof Flying Seastrutz didnt quite fly right-offdrawing-board planned engine check bit taxiing Bob Martin Bruce Selig made bids test fly Weath er good wind steady 10 mph Takeoff required ten feet climb-out dramatic Bob fed full down trim wished Except too much climb ballooning glide first flight great success Bruce verified Bobs findings its first two flights Seastrutz its landplane configuration did rudderelevator maneuvers Bob Bruce could think including inverted flight agreed increased rudder area would useful least 1/8 down trim stabilizer necessary Slow speed flight steady no unexpected snaps next day Ed McCarty flew water tests Wind least 20 mph gusts found place shielded hills Seastrutz steered well water must going enjoy seaplane fly ing got up step ease Although lake deceptively calm trees blowing hill top As usual caution thrown winds theorized float dragwould offset down-trim required land flying set elevator trim zero Takeoff dramatic After 75 feet Continued page 86 January1978 19 Float attachments pine hardwood Left shows pine blocks blind nuts place Hardwood stops right installed after pine blocks have sanded match contours floats Finished cabane struts Fuel tubing pieces installed during assembly provide soft bed wing Struts sewed bulkheads monofila ment epoxied Allows wide tolerance making necessary bendsordinarily problem bending heavy music wire SPECIAL PRO SERIES 2 FOR RC-FREE FLIGHT CONTROL LINE CIAPITCHPRICE 5%3489 63489 733%4119 53%456129 94566% 77%139 10467149 1066V 8W149 to6016159 114677% 7Y, 7%8159 it6E1W169 11%67169 126179 12555179 1356219 1496249 1566309 164%6389 W 55106 BLADE 855 EXTRA WIDE SERIES 400 B Poe SPEED & RACING ADVANCED DESIGN NO 1 IN PYLON RACING LEADING SPEED REGGRO HOLDER OF ALL TIMES RC PYLON RACING DIA PITCHPRICE 6%3%4129 755%6149 7SN 5/N 6N149 8%6% 6% 7 7%7%189 96%7 7A7%189 CONTROL LINE SPEED& RACING CIA PITCHPRICE 4/8A7129 4%55%129 6788%149 7 7%10%11169 889189 89N9%N189 8% 77%189 912 13219 51ARRflW Homebuilts Bill Youmans firstplace win Masters Class Greenville NRCHA Nationals last August seems increasing interest homebuilt helicopters won scratchbuilt own design composite components Bill came within 10 points aceing hover course local flier Norm Holland has developed scratchbuilt using Kavan mechanics tn-cycle landing gear Rev-o-lution canopy Futaba Sl5M ball-bearing servos EK single-stick radio Kraft engine Tach-Tron gover nor weight 12 1/2 pounds very smooth precise enough people inter ested could soon put kit form Look column further details Dual Counter Rotating Head ScratchBuilt Gilbert Laforest Montreal suc cessfully flew counter rotating-head heli copter own design Greenville NRCHA Nats Webra Speed 60 driving both heads unbelievably complicated pushrod system Self-designed transmitter two single sticks dual rudder knobs much Separate collective control head well separate cyclic control Tremendous under taking say nothing about getting mind synchronized hands Radio custom Can-Air Canadian ProLine some radio interference problems Next months column will cover unique finish helicopters first part building Aerospatiale SA-34 1 G Gazelle ducted fan-tail rotor youre flying youre trying hard enough Walt Schoonard 2080 Sharon Rd Winter Park FL 32789 Letters continued page 7 quality Model viation money best model aviation magazine field William R Barr AMA 31415 Claremont CA MA policy publish types models eventually shall get around Mr Barrs suggestions Mistaken Identity No doubt have received few letters already rare event havent would like point out photograph lower right hand corner page 25 Aug 1977 issue Model viation incorrectly captioned gentleman photo Rick Pear son winner last years Soar Nats well other contests sailplane holding Paragon Rick did outstanding job flying under less ideal conditions would shame did receive credit display flying skill Since generally true least 75% sailplanes performance direct function pilots skill would follow mention sailplane used would significant have no doubt uninten tional error know would want errors called attention proper caption can used Ed Slobod Pierce Aero Company Nonthridge CA Size It/Powers continued page 13 ing slower speed reduce somewhat power requirements because scaling down proto type its weight-empty condition rather its gross-weight condition thats ut Size Questions comments may ad dressed Bradford W Powers care magazine Seastrutz/Wi son continued page 18 full throttle some down-elevator Ed pulled up Seastrutz oil like scared duck full stall attitude 50 feet hit wind blowing toward hill blown end-over-end trees Damage minor Test flying continued next week Fall Brimfield meet time stabilizer shim under its leading edge rudder area doubled Seastrutz flew beautifully Among its test pilots Ted Straders son Eric testified flew very much like its predecessor Strutz Echo Seastrutz built mci dences shown will perform very well relatively docile its 46-in wing span compact biplane configuration felt might too quick average flier case diffi cult machine fly land water Have fun Radio Technique/Myers continued page 14 An ammeter measure charging discharging operating currents turntable drum-type chart feed measure servo transmit time shaker find intermittent prob lems heat lamp can Freezit similar chiller locate temperature-sensitive compon ents Special tools various types like desoldering irons Youve seen lot items listed under additional advertisements probability should leave will describe some simple non destructive tests should perform 86 Model Aviation NEWS FLASH Bob Smith Chatsworth CA set new World Speed Record June 19 Pylon mula 11125 RevUp 8%-6% new Pylon RaC ing prop OUT- PERFORMS ALL OTHERS AT THE 1976 NATIONALS 1st RC Masters Class 1st RC Advanced 1st RC Novice 1st RC Sport Scale 1st Formula Pylon 1st Quarter Midget Pylon 1st CL Stunt Open 1st CL Stunt Senior 1st CL Stunt Junior 1st CL Combat O & Sr 1st CL Slow Comb OP & Sr 1st CL Class 0 Speed Open 1st CL Class C Speed Jr & Sr 1st CLCIassB Speed Op & Sr 1st CL Cl Speed Op Sr Jr 1st FE Class B Open 1st FE Class C Open HIGH PERFORMANCE * COMPETITION PROVEN * THIN RIGID BLADES OP HARD MAPLE WOOD * SUPERBLY FINISHED COMPLETELY FUEL PIDOF 1st CL Carrier II Op Jr Sr 1st CL Carrier Jr & Sr 1st CL Formula 40 Opec 1st CL Class 6 Proto Jr
Edition: Model Aviation - 1978/01
Page Numbers: 16, 17, 18, 19, 86
SEASThIJTZ SINCE THIS design developed Ted Straders Strutz-Echo 1967 Wilson seaplane tradition chose Seastrutz its name proved fine flying easily built biplane does great job land sea basic construction built-up balsa straight forward formida ble problem biplane construction cabane struts simplified building jig makes part project snap Good flying characteristics Strutz Echo preserved hopefully im proved following modifications Bottom wing lengthened six inches insure enough area handle added weight floats Total wing area about 515 sq about effective 440 sq multiplied biplane efficiency fac tor 85% Weight tail minimized using covered framework tail surfaces turtleback Flying weight dry 3 pounds Iandplane 4 pounds sea plane Covering nylon over light Silkspan open areas heavy Silkspan over sheet wood except nylon-covered float bottoms Wing loading 196 oz/sq ft landplane 224 oz seaplane 19 ample power As landplane normal three-channel maneuvers performed ease As seaplane loops snap rolls etc possible Seaplane performance realistic takeoffs easy water-handling good Interchangeable water rudder tail wheel fixtures provided Front land ing gear struts lengthened prop clearance water flying wider tracking land Fuselage redesigned use servo tray provide mounting rear float struts inverted building over top view plan Fuselage waterproofed sheeting over opening above lower wing using Nyrod equivalent pushrods gasketing removable front hatch Floats subrudder/water rudder assembly new additions Authors high-step design used flat float bottoms proved other recent seaplanes experience model seaplanes observation full-size seaplanes small distance required between tip step afterbottom step itself can slight still perform its function However height float step tip step top float must great Also rear end float must high enough allow model rotate nose up make angle-of-attack wing least 8o12o too much high-step float bottom allows model rock rotate backward float tip allows maximum lift wings take off step minimizes water drag helping model gain speed water As model rises step wetted area becomes less 16 Model Aviation Next Statue Liberty pose favorite author-model picture Cape Cod author poses landplane version Seastrutz bipe simpleand functional Opposite page floats big enough float modal easilythe first rule float design Above Coming up step Steering good water speeds White circle side medicine bottle cap over charging plug Right Running step touch up elevator airborne holding down model will plane fiat bottoms high speed wish get back quickly beach Developed popular Strutz Echo Ted Strader 19-powered biplane REM controls delight fly land water U George Wilson water drag decreases Bottom float behind step should completely out water during run Construction Instructions assume reader novice step-by-step detail given Construction straight forward sim ple Cabane strut system devised Stra der strong easily constructed recommended jig used assemble struts am partial aliphatic-type glues such Titebond model properly water proofed dry surface immediate ly wet accidentally will have no problem glues avoid white glues Fuselage Bottom built first Cut out main side pieces add plywood doublers p doubler Cut out assem ble bulkheads except firewall sides upside down over plan Dont add bulkhead doublers K L until install front gear struts Firewall motor bearers installed after bottom part removed building board Build hatch sepa rate piece fit neatly bottom part Hatch starts its bottom plate Cut Vs narrower fuselage sides sand edges match slant bulkheads Make cut-out fit fuel tank use Add hatch bulkheads Install side sheeting top sheeting Turtle back cemented directly onto bot tom section Install bulkheads first add stringers filler pieces Double cover section Silkspan Install guide tubes pushrods Dope inside fuselage before adding bottom rear sheet ing Dope inside bottom sheeting before installation Install front gear struts doublers K L before installing front bottom sheeting Add sheeting over lower wing opening after servo tray installed Front hatch water-proofed 1/8 X 3/16 foam rubber gasket attached Pliobond bottom section around outer edges hatch Hatch held down four 2-56 machine screws blind nuts Sufficient pressure required assure tight fit Scuba diving shops may have good fuel-proof foam rubber sheeting Triangular doublers behind cockpit installed before plywood bottom sheeting rear float strut mounting sheeting has blind nuts rear strut screws installed before cementing place Blind nuts tail wheel/sub-rudder installed before bottom sheeting tail cemented place Tailwheel/Suh-Rudder These assemblies built very hard balsa base plates strength minimize crushing holddown screws Use washers under bolt heads help spread load Sections dowels short lengths tubing inset places take pressure screws Hinge tubes 1/16 ID nylon sewn epox ied place Use thin monofilament fish line reinforcing joints figure-8 hinges Floats Construction similar used fuselage Assemble sides bottoms bulkheads over set lines drawn separate sheet Add bottom sheeting fore removing basic assemblies build ing board Remove board add top bulkheads Dope inside floats inside sheeting used cover float tops Add upper side sheeting upper top sheet ing Cut pine blocks strut mounts care fully install blind nuts Mark locations strut stops pencil Dope bottoms install floats Trim bottoms upper side sheeting using razor plane sandpaper Install shape nose blocks Install triangular stops struts Angle floats respect thrust line overly critical prefer degree two negative angle top-of-float thrust line minimize air drag increase maximum takeoff rotation angle Float angle set bending rear struts slight ly less angle between rear strut legs will change angle neatly Inter-float strut spruce hard pine sanded streamlined shape between floats Ends fit snugly between stops float tops Tail Surfaces parts including sub-rudder built 3/16 sheet strip Use light good-quality wood minimum weight anti-warping Center member stabilizer rear upright sub-rudder medium hard strength January 1978 17 air Seastrutz realistic yet agile enough loop roll its 19 engine nI1TI-- i III rII~--I iEEtzic ~__- ILii i IIN/N ANTTTTSXXL -F II IIIIWIIIGSTTON lAIN BALSA--1I IiIIISATUNLESSSOTSTii IFNAAE7IAANANAWIWISYTTAL SO/N BASS LA WI vW~iirTIT----ySTl1I1rIi III r III III I I ZiF-~Iz.LSNYBNBYAN XBTWIAN ONIflBEXWI TB/NIiIA BA WINO 6/ABLA B AT AlA N/NO AlASEE TEXTLISA B/SNAB r OLITTASEXXLOX TIt Y--rkLA XXIII1II1NBXEIXBB Y-A-- BNYTET/ILAAANASOWITSAABXS I/BANG /10OSNLYXA/BBliiIIABASTIBOSALNE STATBASONBTLONAXLAANN NON/NA TTXTOA-BA BAITS/A- B IIN-tNXBNLSFUSELAGE ANN FLOATS FROAXN BLISS BATS IA WIOG/WIBSIX BATSI/N BALSA SAT UNLESS NOTES EBB SAL WIN I/N SAT IN XL 14I1~~~ AlBSBIA I BA BAIii I1 NSBAISASASWIFTBTFNNBSI1 SNISATI BASIS5 LB BAtlBSIIINNNT N BAN T/BA/AX/TLXNNA5 LBI/B AXTABAXONS rAOTIGSAAL ISTSUTX FETAl ST TED STNAOEN eNSEAPLANE UPDATE BY XTOTOE WILSON STRU TZ FULL-SIZE PLANS AVAILABLE Note plywood side pieces inset lower extreme rudder absorb beating tailwheel water-rudder control links Original model used nylon monofilament figure-8 stitches SEEPAGE 104 Wings Both wings built over plan Build dihedral brace first panel wing Join two halves before top sheeting added Order assembly follows Pin down bottom sheeting Cement dihe dral brace spar Position spar install ribs pinning place until glue dry Angle center rib match dihedral Install leading edge Install 3/8 sheeting center top wing Remove first panel Cabane Strut jig shown place top fuselage simplifies construction strut assembly insures accurate alignment Plywood used liberally doublers gear mounting Quarters used balance picture Note hatch holddown blind nuts 18 Model Aviation I- I K III SNEEr USLOBS BOrONI BtBmPU~ 1 IrOOU--OBOWN Br ocosor WILSONIS NOV IBiS lOVES 0050W IHOBYOLL board build second panel using same order assembly First panel blocked up dihedral angle sec ond panel being built Washout built wings top sheeting being installed Pin leading edge center rib panel build ing board Block up rear wing tip amount washout shown plan pin place Block trailing edge up two three other places between tip center making straight line center-to-tip Install leading edge sheeting center sheeting trailing edge sheeting Amount washout overly critical Just make sure both sides have equal amounts washout Model stable slow speeds has no tendency snap-roll Tip blocks installed after have rough shaped Trim sand after place Cabane Struts Until cabane strut jig came mind dubious about building bi plane Vertical wooden struts used model designs solve problem prac tical pretty manner Jig built material must accurate provides places rest tips wing supports being attached struts done struts position fuselage jig resting atop part fuselage normally under hatch First build jig Cement stops center fuselage simplify positioning building struts Next bend approximate shape two U-shaped pieces 1/8 music wire two 1/16 music wire tie struts Cut two 1/8 mw wing supports length Using rubberbands soft wire #16 18 solid copper mount wing supports jig fit U-shaped pieces Rebend necessary fit neatly slot through fuselage reason able fit wing support satisfied fit bind ends wing supports using thin copper wire apply flux solder Before second U strut remove partially made assembly jig slip piece silicone rubber tubing over center part wing supports makes soft non-slip mount wing Push tubing far can toward solder joints Fit attach second U-shaped piece Tie struts fitted bound fluxed soldered Finished strut assembly slips off jig little difficulty Strut assembly mounted fuselage using nylon monofilament line epoxy produces well-aligned top wing mount Finishing Insides structures sealed dope thinned epoxy Hobby poxy Formula 2 diluted l-to-l thin ner 90% isopropyl alcohol good sealer Seal inside pieces used close structure model finished using Silkspan over wood except float bottoms nylon covered Open areas covered light Silkspan nylon Heatshrink materials easy waterproof Flying Seastrutz didnt quite fly right-offdrawing-board planned engine check bit taxiing Bob Martin Bruce Selig made bids test fly Weath er good wind steady 10 mph Takeoff required ten feet climb-out dramatic Bob fed full down trim wished Except too much climb ballooning glide first flight great success Bruce verified Bobs findings its first two flights Seastrutz its landplane configuration did rudderelevator maneuvers Bob Bruce could think including inverted flight agreed increased rudder area would useful least 1/8 down trim stabilizer necessary Slow speed flight steady no unexpected snaps next day Ed McCarty flew water tests Wind least 20 mph gusts found place shielded hills Seastrutz steered well water must going enjoy seaplane fly ing got up step ease Although lake deceptively calm trees blowing hill top As usual caution thrown winds theorized float dragwould offset down-trim required land flying set elevator trim zero Takeoff dramatic After 75 feet Continued page 86 January1978 19 Float attachments pine hardwood Left shows pine blocks blind nuts place Hardwood stops right installed after pine blocks have sanded match contours floats Finished cabane struts Fuel tubing pieces installed during assembly provide soft bed wing Struts sewed bulkheads monofila ment epoxied Allows wide tolerance making necessary bendsordinarily problem bending heavy music wire SPECIAL PRO SERIES 2 FOR RC-FREE FLIGHT CONTROL LINE CIAPITCHPRICE 5%3489 63489 733%4119 53%456129 94566% 77%139 10467149 1066V 8W149 to6016159 114677% 7Y, 7%8159 it6E1W169 11%67169 126179 12555179 1356219 1496249 1566309 164%6389 W 55106 BLADE 855 EXTRA WIDE SERIES 400 B Poe SPEED & RACING ADVANCED DESIGN NO 1 IN PYLON RACING LEADING SPEED REGGRO HOLDER OF ALL TIMES RC PYLON RACING DIA PITCHPRICE 6%3%4129 755%6149 7SN 5/N 6N149 8%6% 6% 7 7%7%189 96%7 7A7%189 CONTROL LINE SPEED& RACING CIA PITCHPRICE 4/8A7129 4%55%129 6788%149 7 7%10%11169 889189 89N9%N189 8% 77%189 912 13219 51ARRflW Homebuilts Bill Youmans firstplace win Masters Class Greenville NRCHA Nationals last August seems increasing interest homebuilt helicopters won scratchbuilt own design composite components Bill came within 10 points aceing hover course local flier Norm Holland has developed scratchbuilt using Kavan mechanics tn-cycle landing gear Rev-o-lution canopy Futaba Sl5M ball-bearing servos EK single-stick radio Kraft engine Tach-Tron gover nor weight 12 1/2 pounds very smooth precise enough people inter ested could soon put kit form Look column further details Dual Counter Rotating Head ScratchBuilt Gilbert Laforest Montreal suc cessfully flew counter rotating-head heli copter own design Greenville NRCHA Nats Webra Speed 60 driving both heads unbelievably complicated pushrod system Self-designed transmitter two single sticks dual rudder knobs much Separate collective control head well separate cyclic control Tremendous under taking say nothing about getting mind synchronized hands Radio custom Can-Air Canadian ProLine some radio interference problems Next months column will cover unique finish helicopters first part building Aerospatiale SA-34 1 G Gazelle ducted fan-tail rotor youre flying youre trying hard enough Walt Schoonard 2080 Sharon Rd Winter Park FL 32789 Letters continued page 7 quality Model viation money best model aviation magazine field William R Barr AMA 31415 Claremont CA MA policy publish types models eventually shall get around Mr Barrs suggestions Mistaken Identity No doubt have received few letters already rare event havent would like point out photograph lower right hand corner page 25 Aug 1977 issue Model viation incorrectly captioned gentleman photo Rick Pear son winner last years Soar Nats well other contests sailplane holding Paragon Rick did outstanding job flying under less ideal conditions would shame did receive credit display flying skill Since generally true least 75% sailplanes performance direct function pilots skill would follow mention sailplane used would significant have no doubt uninten tional error know would want errors called attention proper caption can used Ed Slobod Pierce Aero Company Nonthridge CA Size It/Powers continued page 13 ing slower speed reduce somewhat power requirements because scaling down proto type its weight-empty condition rather its gross-weight condition thats ut Size Questions comments may ad dressed Bradford W Powers care magazine Seastrutz/Wi son continued page 18 full throttle some down-elevator Ed pulled up Seastrutz oil like scared duck full stall attitude 50 feet hit wind blowing toward hill blown end-over-end trees Damage minor Test flying continued next week Fall Brimfield meet time stabilizer shim under its leading edge rudder area doubled Seastrutz flew beautifully Among its test pilots Ted Straders son Eric testified flew very much like its predecessor Strutz Echo Seastrutz built mci dences shown will perform very well relatively docile its 46-in wing span compact biplane configuration felt might too quick average flier case diffi cult machine fly land water Have fun Radio Technique/Myers continued page 14 An ammeter measure charging discharging operating currents turntable drum-type chart feed measure servo transmit time shaker find intermittent prob lems heat lamp can Freezit similar chiller locate temperature-sensitive compon ents Special tools various types like desoldering irons Youve seen lot items listed under additional advertisements probability should leave will describe some simple non destructive tests should perform 86 Model Aviation NEWS FLASH Bob Smith Chatsworth CA set new World Speed Record June 19 Pylon mula 11125 RevUp 8%-6% new Pylon RaC ing prop OUT- PERFORMS ALL OTHERS AT THE 1976 NATIONALS 1st RC Masters Class 1st RC Advanced 1st RC Novice 1st RC Sport Scale 1st Formula Pylon 1st Quarter Midget Pylon 1st CL Stunt Open 1st CL Stunt Senior 1st CL Stunt Junior 1st CL Combat O & Sr 1st CL Slow Comb OP & Sr 1st CL Class 0 Speed Open 1st CL Class C Speed Jr & Sr 1st CLCIassB Speed Op & Sr 1st CL Cl Speed Op Sr Jr 1st FE Class B Open 1st FE Class C Open HIGH PERFORMANCE * COMPETITION PROVEN * THIN RIGID BLADES OP HARD MAPLE WOOD * SUPERBLY FINISHED COMPLETELY FUEL PIDOF 1st CL Carrier II Op Jr Sr 1st CL Carrier Jr & Sr 1st CL Formula 40 Opec 1st CL Class 6 Proto Jr