NEAT constant-tension winch Jack Perecman Golden Valley MN sent excellent photos very neat winch Jacks letter tells about Enclosed will find some photos showing constant-tension winch designed built winch presently its second season far has proven quite reliable Im mem ber Minnesota RC Soaring Society have used winch both club fun-flys contests motor starter motor Johnson outboard has high torque plus ad vantages both long shaft thread end splines near motor face make mounting drum quite easy photo shows winch turnaround transportation mode Another photos shows right side winch its operating position wheels have flipped out underneath frame now resting ground foot treadle behind attached winch means bicycle brake cable operation farther treadle pushed down greater tension line T handle device top battery emer gency kill switch threaded rod crank low motor pivots motor/drum assembly fine adjustment line level winding final photo shows main parts constant-tension device Pushing down foot treadle pulls cable causes switch arm pivot counterclockwise away spring-loaded roller arms microswitch normally closed As soon switch pulled away roller arms closes en ergizes solenoid supplies power motor As tension line increases roller arms begin pivot toward switch ten sion line counterbalanced two springs desired tension achieved left roller arm touches microswitch open ing turning off solenoid will stay off until tension line decreases greater tension desired operator pushes foot treadle down pulls switch farther away roller arm springs have stretched before arm contacts switch operation due dampening effect stretch line way device automatically pulses motor off very similar what operator would using normal foot switch Other features include one-way clutch roller can engaged disengaged moving 44 Model Aviation Radio Control Soaring Byron Blakeslee 3134 N Winnebago Dr Sedalia CO 80135 Four Ts Teutonic Tailless Terror Team Germany flew Viking Cup Slope Races held Denmark Note models has some sort experimental aftmounted horizontal stability augmentation surface model just front has extended fu selage central fin other wings use tip-mounted fins Photo Preben Norhoim Swiss team Viking Cup meet Manager RoIf Gersberger right Norholm Jack Perecman designed winch its constant-tension mechanism Motor starter Johnson outboard motor Jack en gineer 3M company designs sort thing living Items note T-handled kill switch mounted right bat tery terminal extra-heavy battery post clamps flip-up wheel carriage Foot treadle gas pedal tells winch much tension put towline winch motor cycles automatically maintain desired tension Author Blakeslee has info column small black lever seen just above center shaft clutch roller uses Torrington oneway roller bearing addition just below roller mounted roller arm small tri angular piece urethane rubber rubs rim drum effectively brakes drum slightly prevent backlashes main purpose building winch first see simple reliable constant-tension device could built F3B competition days weak link Second perhaps applicable average club putting stop switch arm possible easily ad just maximum tension pilot can achieve using winch have able launch Gnome hand-launched Glider immediately readjust winch launching Windsong addition possible beginners have con fidence launching airplanes fear folding wings can see what beautiful job engineering fabricating Jack did winch especially constant-tension device CT mechanism would course work winch just Jacks outboard-motor design Some careful machinework would need done duplicate though Jack said hed make drawings avail able theres enough interest can con tact Jack Pereeman 224 Natchez Ave North Golden Valley MN 55422 Incidenially winches should have kill switch similar Jacks cut off battery power case emergency common situ ation stuck solenoid tries strain plane through turnaround need switch can operate quickly state severe panic RV shops sell big copper knife switches about $20 mount right battery post Theyre cheap insurance Danish connection risk infringing Mark Triebes turf Id like print letter friend Preben Norholm Copenhagen describing 1989 Viking Cup Race Vi king Cup biggest annual International F3F event held North Sea slopes near Hanstholm Denmark last June F3F FAI Provisional event Slope Racers fly 10 laps 100-meter course against clockone plane time Slope Racing US traditionally run exciting way te wtth four planes flying against other heat However Europeans decided certain prospect midair collisions consequent loss hundreds dollars worth planes equipment sufficient rea son race one-at-a-time Preben founders F3F Racing justifiably proud success Viking Cup has achieved Preben too beauty event like gathering gether enthusiasts different coun tries Preben would like US fliers participate too team South Bay club got serious thinking stage couldnt quite man age trip 89 Maybe next year Isnt wonderful have hobby/sport can travel almost country world welcomed instant friends identical interests Prebens letter ended up 40 contestants coun tries spread Iceland Israel almost everything between came Switzer land Bavaria Berlin Westphalia Osnabruck area England Scotland Norway Nic Wright England won again Denmark took team trophy followed England NorIv finest model building equipment manufactured kahe4 zfloS4loAuh1wi 4ohrk a41/i/nna 94eady& Mdc dealer order direct-500A Magic Magnet Builder Icontains 16x48 Steel Base Plate 30 Magnets 10 stands S 9450 SOOB Master Magic Magnet Builder Icontains 1 6x4B Steel base plate 60 Magnets 20 stands 10 Vert press 10 steps 20 rib holders 50 sets nuts & bolts$16895 503B Base Plate Extension 1 6x1 6 Steel Base plate building giants$ 2695 501A Unassembled Magnets 10 pak$ 1195 501 B Assembled Magnets 10 pakS 2200 502 Stands 110 uprights primarily fuselage easyS 950 504 Vertical press 5 pak holding spars leading trailing edges position$ 995 505 Steps 5 pakl adjustible leading & trailing edge positioning$ 595 506 Rib Holder 10 pak Use magnet building faster$ 995 ~TUFELDON J LIND COMPANY 3151 Caravelle Dr Lake Havasu City AZ 86403 C 16021453 7970 Send sell addressed stamped envelope catalog ot products M/C & Visa accepted December 1989 45 Fourmost Fuselage Fixture Mark II Fourmost Fuselage Fixture Mark II designed auto matically align fuselage structures built strings measuring eyeballing Price $5995 Simply slide four centering brackets track until align fire wall tail joint two bulkheads Clamp fuselage together lightly rubber bands structure will straight ready gluing Fixture will accomodate fuselages long four feet wide eight inches eight inches Please include $400 br Shipping Handling direct orders FOURMOST PRODUCTS 4040 24TH AVEFOREST GROVE OR 971165031 357-2732 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NiCd Batteries Ihe chargers YOU need packageFor Cycier-Chargec,,,, $23996 Fits 48V Rs 96V Tx packsPlus ened Ceii Others avaable write kier.. *3495Reguiar Modei $4696 ForPlus $3 S&H\ eiFor held kit smatPlus $3 S&H tipleelectric boat batteriesSpecify 612 24V Heavy Duty Model.. $5896 sport winch large boat andPlus $4 S&H electric power charging batteriesSpecify 6 1 2V CaRa Products ox 221 DealerinqurneslnveedCanton SO 57013 pp THERMAL CHARGER what looking electric sailplane good looks easy build fun fly great performance Thermal Charger Wing Span Wing Area Motor Included 60 Inches 545 Sq Inches Leisure 05 Electric C — t PRECISION PRODUCTS INC 714 592-5144 510 E Arrow Highway San Dimas CA 91773 way first day just little wind ran practice round let fliers prac tice own afterwards needed especially Alps because unfamiliar seaside slopes winds second day shot four good contest rounds fairly good west wind third day rather weak winds did round Some fliers went sight seeing some stayed practice fourth day expected good north winds finally arrived 12- 20-mph winds directly best slope made five rounds dinner delayed until 800 pm Rain forecast next day turned out expectedan off day kept people busy think happy time Evening entertainment included RoIf Girs berger designer RG series airfoils new Chairman FAI s F3B ClAM Subcom mitteeBB telling about airfoil develop ments showing Selig-Donovan Princeton wind tunnel video several times very popular conference about F3F rules future Viking Races took two hours de cide rules great meet again Derbyshire England October 1990 RoIf also showed two films about modeling full-scale gliding Switzerland 1942-44 100% professionally done included some unique things films original purpose PR Swiss Army Air Force long rainy day off Chas Gardner Brian Sharp England Scotland told about British Slope Cross-Country Racing ended 20-minute presentations six interesting thought planes entered contest pilots plus sometimes interpre ter Very popular too course pilots se lected very proud have opportunity tell about marvelous designs 'Then time get dressed banquetand long happy night special Viking Year award went Siegfried Schedel Bavaria Siegfried started out looking very much like beginner F3F practiced minute could find climbed steadily scoreboard ended fifth place beating 80% winning Danish team agreement best man won no protests during contest Includ ing practice must have close 1000 flights two three models minor damage landings com pletely repaired hour 'The next morning everybody packed went home again Anna Johannes owners Vigso Bugt Pension everyone stayed BB happy too said never better guests wished us come back soon hope will have success new American Sportsman F3B class dont know told fact F3B contests Denmark according local Sportsman rules far biggest problem num ber officials needed So decided cut down simply taking five steps 1 Eliminating Distance task altogether 2 Fly Duration task individual flights after another no group scoring 3 No working-time slots 4 Organizer-supplied winches 5 Only attempt flight tough pop off Its far simpler contest run because everybody can help another same way normal American Duration-only contest challenge airthe six-minute Preci sion Speed runis exactly same real F3B course guys would have liked fly Distance no way can make work Three weeks ago ran National Cham pionship F3B have separate Nats classes F3A F3B F3C etc 18 pi lots zero officials fixed se quence flying timekeeping flagging etc CD himself managed place second course way setting up will produce some breaks since people active time lunch break must put managed seven rounds two days including early dinner Sunday night Italian pizza res taurant everyone 15 50 years great fun Next weekend will busy practicing F3B team Paris Preben Danish teams managerBB have good team time mean have some bright young people team gonna win anything down Paris certainly will middle time team does have strongest men eitherthe members spread second tOth place Nats will survive physi cally mentally hope will learn some thing can used Czechoslovakia next year 1990 European F3B Championships Netherlands -1991 F3B World Championships Only has made Speed task better 18 seconds official contest dont count practice runs arrive Paris day before practice round would have liked few days 46 Model Aviation durable skis made lightweight aluminum feature steel spring holds ski rigid flight also elevates axle above ski no modifications cur rent gear wire needed can go wheels skis seconds side ski also has special edge allows excellent tracking icy surfaces avalisbie three sizes snd can purchased trikes just mains order please send check money order $200 shipping handling Add 8% sales tax Minnesota Allow 2 weeks delivery large scales please submit weight wing span Telephone inquires call Ron 612-781-7333 NORTHERN 20 30 Trike $2000 Mains $1500 MODELING 40 60 Trike $2200 Mains $1700 PRODUCTS Large Scale Trike $7500 Mains $5500 PO Box 21181 ColumbIa Heights MN 55421 781-7333 DIAMOND ShARPENS BLADES NA JIFFY GET GREAT EDGE ON THAT NO11 OR UBER SKIVER BLADE COMES WITH REVERSIBLE BLOCK 325 grit 1000 grit $1500 Replacement Block$850 ADD $175 P&H 6% sales tax CA AVAILABLE CERAMIC AND ARKANSAS WHETSTONES P 0. BOX 8 MOORPARK CA 93020 805 529-9313 short money time again Prebens letters always fun read full good information great time Preben 1987 following Osnabruck F3B World Champs staying same pension flying same slopes talked ahout wind north-facing bluff high above beach cant imagine finer place Slope flying once wrote bluff must 400 ft high Preben later called attention fact highest spot Denmark 350 ft still say looked high time remarks about fly F3B con tests could food thought US CDs run ning Sportsman multitask events Because no hard-and-fast rules can run SMT contests way makes sense local conditions Wingspan winch launches windspeed Wisconsins Lee Murray kind enough write share some interesting data proj ect has working Back 1986 several Sailplane fliers club began collect records flights IIIBTBI2IIN 11$ ELIcIT tITlES PndlgJ II HIngE. 33-3344-1346-774 Ill MItag learn about performance various mod els effects flying conditions etc records now include over 250 flights provide some insight flight performance related windspeed launch methods Sailplane type Virtually flights club field sod farm often damp compared higher ground evaporative cooling often limits thermal generation Location would important consideration comparing results tween clubs Winch launches using Two-Meter Prodi gy resulted flights 25 seconds longer av erage high-start widely recognized difference performance between wingspans also evident shown chart below AWRACE FLIGHT TIME VT HIIECSPHN 336 FlIght Histopa ii isA N1a Aa 3p 4 TIHH IN iI121IN146SB WII4GNFBS PPndlgyB 50-4 B CopiloA comparison theoretical flight times suggests effect involves differ ences sink rate difference between 2M Standard class 78 vs 100 larger difference between Standard Unlim ited Class 2M class RO-8 has old standby years E-205 wing pro file substituted performer Prodigy shows up also Flying moderate wind does decrease flight times based Prodigy flying off highstart chart titled Flight Times vs Windspeed shows relationshipwhich fact undoubtedly linear lack data shown linear Flight lAment WinO Spa. Pndlns-IhIhnlapt Sa N6 Ia N 3 lend Spend reason flight times appear correlated windspeed probably related getting height launches since winch flights did show same correlation Model & Average Flight Times Minutes 2-Meter Prodigy RO-8 Std Class Cumic XC/Unlimited Dynasoar Scale ASW-17 526 465 891 1022 428 As know am big advocate theoreti cal Sailplane performance analysis Lee John Hohensee developed market computer Sail plane design/analysis programs called PC-Soar MaxSoar BB Part quest tie theory reality analysis actual flight per formance Al Scidmore Professor Electrical Engineering University Wisconsin pursuing instrumentation Sailplane digital data logger hope someday ALL STAINLESS STEEL HEAD LITE IItm BEST GLOW PLUG CONNECTOR Stainless Steel HEAD LOCK BEST DESIGN Welded No Solder Acid Flux Flexing Wires BEST NiCad Field Replaceable 12 AH SANYO 15 AH PANASONIC BEST QUALITY & GUARANTEE MODEL PRODUCTS CORPORATION BEST PRICESt #045-WIO NiCad Charger$ 995 available write directSt #040-With NiCad$ 1595 add $100 $200 outside US St #041-With NiCad & Charger $ 2595 MODEL PRODUCTS CORP PO Box 100 Allamuchy NJ 07820 201850-1508 December 1989 47 will able share some hard numbers Sailplane performance have calibration data first versions altimeter temperature sensor sup ply voltage monitor velocity sensor Al has some improvements under way altitude velocity Tbe equipment will small enough fit inside X-Country Scale ships can mounted pod above wing smaller models would nice transmit digitally encoded data ground someone would like get involved would love bear him Presently sensor outputs 0-20 VDC Drop line Lee Murray 1300 Bay Ridge Road Appleton WI 54915 phone 1-414/7314848 Lees letter reminder its good idea keep logbook Gliders Person ally usually dont note time flight enter date place number flights windspeed flying conditions weight ballast used results changes trim reason recording flight times during prac tice session maximum time launch objective Practice occasion perfecting pre cision landing one-minute countdown trying out different thermaling techniques general doing wild crazy things dont dare try during contest Id like review about practice sessions future column Please write youd like share favorite meth ods How-to-make-molds video previously re viewed two Julian Tamezs instructional videos titled Vacuum Bag Cut ting Foam Cores Now Ive chance see Julians 34-hr tape called Making Fiberglass Molds Let tell theres lot informa tion Julian partner Greg Norsworthy go through process making fiberglass fuse lage Cross-Country ship start making plug making fiberglass molds finally laying up two halves fu selage joining together whole pro cess takes good deal time involves lot skill tricks trade As Julian says tape gives ABCs making molds what equipment materials will need manufacture kind fiber glass part have idea youd like make own F/G fuselages guarantee studying tape will save much time aggravation kept returning thought watching Guys like Bob Sealy Jerry Slates really earn money make nice fuselages such reasonable prices three Julians tapes $3495 less 20% NSS LSF members plus $350 shipping address Channel Productions 19827 Bishops Gate Suite No1 Humble TX 77338 Phone 1-713/443-1253 days 5403944 evenings Sportsman Multi-Task update winner isMark Allens Falcon 880 course Im re ferring Jim Grays RIC Soaring Digest Chal lenge Design contest Sportsman Multi-Task SMT Sailplanes very interesting competition because good de signs entered including several brand-new ones says Soaring lacking new exciting things days addition winning Falcon 880 featured October column other designs en tered alphabetical order Bob Dodgsons Camano Terry Edmonds Callisto Don Chan ceys Conquest Don Edbergs Hustler Jeremy Teos Odyssey Bob Sealys Pulsar Paul Carlsons Quasoar Max Mills Westwind Sportsman Multi-Task new contest con cept Its takeoff F3B Duration/Distance Speed task flying restricted aircraft simplified flexible contest operation SMT suitable intermediate-level fliers say about LSF Level 3 designed middle ground between AMA Thermal Duration flying real International F3B Soaring competi tion limitation maximum weight SMT planes intended keep Gliders nonintim idating Sportsman-level fliers Thermal Duration will always bedrock Soaring USA youll find addi tion some Distance Speed tasks just adds fun makes quite different ball game Sailplane fliers say looking something new challenging think SMT will provide excitement seek ing restriction SMT planes must weigh 75 oz ballast pretty well excludes F3B planes permits just about kits market plus original de signs approximately two-meter 115-inspan size range Now suggested SMT contest rules place see October column have de sign RCSD jury feels good plane event next step clubs around coun try try SMT contests practice sessions see works club has run Distance Speed tasks before first problem will making 3 New ARFs ZMP SUKHOI Su-26M 1/5 ScaleIMPALA Masters Pattern span 68 area 890 sq motor 4 stroke 120 equivspan 66 area 800 sq motor 4 stroke 120 60 rear Preassembled lightweight epoxy fuselage sheeted plug-in wingsPresssembled balsa fuselage veneersd plug-in wings 8 stabs sheeted stab fin & rudder 5 dia epoxy cowl texan canopy &Epoxy cowl pipe cover removable canopy Illustrated illustrated assembly manualassembly manual see hobby dealer order direct MONARCH AMA Sport Pattern span 66 area 750 sq motor 4 stroke 90 60 Cu Preassembled balsa fuselage venesred wing shaped balsa parts texan canopy epoxy cowl illustrated assembly manual c ZIMPRO MARKETING tu sOt arK OAK StOOL 55 35535 P001St 515 482 6155 48 Model Aviation AIR WOLF EPOXY FIBERGLASS FUSELAGES TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $21000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 Z ial Introductory Offer Frequency Conversion $3500 Includes Crystals Certification Special Fast Turnaround Now Available CALL Send Large Self Addressed Envelope Brochures UPS U S Mail Federai Express Used Mastercard Visa Accepted pair sighting devices used define two dimensionless planes 150 meters apart known Base Base B two bases just big windows sky delineate distance Glid ers need fly leg Speed Distance circuit RMSA PPSS clubs Colorado fly quite bit Distance club contests weve found hoop-on-a-tripod sighting device both simple make easy use first described Dan Pruss June 1983 Soaring column thismagazine dont save old sues MA send business-size envelope 25C stamp Ill return reprint Dans column showing make sighting device quick description Pruss sighting device 36-in length %2 music wire stuck holes drilled opposite sides plastic like Lucite metal block about 15 20 side A-in hole drilled precisely 900 %2 holes Through hole inserted 10in length A-in-GD brass tube bottom block drilled No 7 drill tapped x 20 attachment camera tripod operation set up sighting device near winches Base walk 150 meters upwind F3B crosswind AMA rules set down other sighting device Base B just look through brass tube sight Base device adjust ing head tripod Doing same thing Base Aie sighting Base B deviceguarantees wire hoops both bases exactly parallel other Necking down end brass tubes soldering short pieces two-nextsmaller-size tubes makes sighting process precise look through big end 150-meter distance can laid out measured length cable fishing leader stored fast-wind spool Just play out walk Base B wind up walk back whole procedure can done faster setting out winch Speed task run flier time flagger required Base B flag ger puts up flag Glider about half way Base B drops Glider breaks plane defined wire hoop flag must stay up Glider fails break planeie cuts turnso pilots timer can tell him go back try again timer usually calls Base turns pilot pilot needs stand near timer Base sighting device practice its best pilot get lined up Base can judge turn himself instead waiting Turn call Distance task usually run four pi lots flying man-on-man although can done time small contests needs flagger differently colored flag Base B plane four planes per heat youll need flaggers red white blue green colored flags course need establish before launching color signed pilot Holding up red white blue green flag also holding up Glider helps Base B crew determine plane flag Also weve found inex pensive Radio Shack-type two-way radio set very helpful communicating back forthISO meters just bit too far shouting As mentioned above first time two flying SMT need called contest Its good schedule couple practice sessions everyone gets hang flying Speed Distance tasks well getting accustomed flagging jobs Give try Please let know works out Airfoils Low Speeds title 398-page book Michael Selig John Donovan Da vid Fraser reporting long-awaited results tests using Princeton Universitys lowspeed wind tunnel book being published Herk Stokely Soartech #8 sells $20 ppd may order now Herk 1504 Horseshoe Drive Virginia Beach VA 23451 Princeton tests probably exten sive best controlled investigation model Sailplane airfoils ever done As such Sailplaners have extremely anxious read about what Michael John Dave have discoveredand some new super airfoils will forthcoming So Soartech #8 should very interesting popular read David Fraser also designer popular Sailplane Design computer program lat est Version 30 has Princeton data cludes 87 airfoils including flapped tripped versions David says Its quite gold Version 30 sells $35 Version 2 users can updated 30 returning diskette $10 Write Sailplane Design 1335 Slaton Dr Maple Glen PA 19002 Torrey Pines Scale Fun Fly Its short notice over Thanksgiving weekend Friday through Sunday Torrey Pines Gulls club will put Scale-only Slope Fun Fly fa mous Torrey Pines site just north San Diego Charley Morrey Slope Soaring News wrote invite Scale fans come fly Charley said details hadnt nailed Continued page 156 December 1989 49 Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royal Tower Hobbies World Engines Spectrum Analyzers CalIbrated Test Instruments Large Inventory RIC Parts Crystals THE PIPER BRAVE scale model Pipers latest Ag plane t wing span 30-33 lbs 5 cc power lb payload ational flaps hopper door onal Spreader Kit formed aluminum landing gear rglass cowls um-formed canopy tucted extruded foam ply hardwood E $269~ OPTIONAL $ 4fl95 Smoker l actually dusting KITSPREADER SEND $100 FOR CATALOG OFQ 4/RT 1 NEODESHA KS 66757 SAC KITS AND ACCESSORIES316 325-2821 Free Shipping Kit OrdersScott Airplane CompanyVISA/MASTERCARD GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation
Edition: Model Aviation - 1989/12
Page Numbers: 44, 45, 46, 47, 48, 49, 156
NEAT constant-tension winch Jack Perecman Golden Valley MN sent excellent photos very neat winch Jacks letter tells about Enclosed will find some photos showing constant-tension winch designed built winch presently its second season far has proven quite reliable Im mem ber Minnesota RC Soaring Society have used winch both club fun-flys contests motor starter motor Johnson outboard has high torque plus ad vantages both long shaft thread end splines near motor face make mounting drum quite easy photo shows winch turnaround transportation mode Another photos shows right side winch its operating position wheels have flipped out underneath frame now resting ground foot treadle behind attached winch means bicycle brake cable operation farther treadle pushed down greater tension line T handle device top battery emer gency kill switch threaded rod crank low motor pivots motor/drum assembly fine adjustment line level winding final photo shows main parts constant-tension device Pushing down foot treadle pulls cable causes switch arm pivot counterclockwise away spring-loaded roller arms microswitch normally closed As soon switch pulled away roller arms closes en ergizes solenoid supplies power motor As tension line increases roller arms begin pivot toward switch ten sion line counterbalanced two springs desired tension achieved left roller arm touches microswitch open ing turning off solenoid will stay off until tension line decreases greater tension desired operator pushes foot treadle down pulls switch farther away roller arm springs have stretched before arm contacts switch operation due dampening effect stretch line way device automatically pulses motor off very similar what operator would using normal foot switch Other features include one-way clutch roller can engaged disengaged moving 44 Model Aviation Radio Control Soaring Byron Blakeslee 3134 N Winnebago Dr Sedalia CO 80135 Four Ts Teutonic Tailless Terror Team Germany flew Viking Cup Slope Races held Denmark Note models has some sort experimental aftmounted horizontal stability augmentation surface model just front has extended fu selage central fin other wings use tip-mounted fins Photo Preben Norhoim Swiss team Viking Cup meet Manager RoIf Gersberger right Norholm Jack Perecman designed winch its constant-tension mechanism Motor starter Johnson outboard motor Jack en gineer 3M company designs sort thing living Items note T-handled kill switch mounted right bat tery terminal extra-heavy battery post clamps flip-up wheel carriage Foot treadle gas pedal tells winch much tension put towline winch motor cycles automatically maintain desired tension Author Blakeslee has info column small black lever seen just above center shaft clutch roller uses Torrington oneway roller bearing addition just below roller mounted roller arm small tri angular piece urethane rubber rubs rim drum effectively brakes drum slightly prevent backlashes main purpose building winch first see simple reliable constant-tension device could built F3B competition days weak link Second perhaps applicable average club putting stop switch arm possible easily ad just maximum tension pilot can achieve using winch have able launch Gnome hand-launched Glider immediately readjust winch launching Windsong addition possible beginners have con fidence launching airplanes fear folding wings can see what beautiful job engineering fabricating Jack did winch especially constant-tension device CT mechanism would course work winch just Jacks outboard-motor design Some careful machinework would need done duplicate though Jack said hed make drawings avail able theres enough interest can con tact Jack Pereeman 224 Natchez Ave North Golden Valley MN 55422 Incidenially winches should have kill switch similar Jacks cut off battery power case emergency common situ ation stuck solenoid tries strain plane through turnaround need switch can operate quickly state severe panic RV shops sell big copper knife switches about $20 mount right battery post Theyre cheap insurance Danish connection risk infringing Mark Triebes turf Id like print letter friend Preben Norholm Copenhagen describing 1989 Viking Cup Race Vi king Cup biggest annual International F3F event held North Sea slopes near Hanstholm Denmark last June F3F FAI Provisional event Slope Racers fly 10 laps 100-meter course against clockone plane time Slope Racing US traditionally run exciting way te wtth four planes flying against other heat However Europeans decided certain prospect midair collisions consequent loss hundreds dollars worth planes equipment sufficient rea son race one-at-a-time Preben founders F3F Racing justifiably proud success Viking Cup has achieved Preben too beauty event like gathering gether enthusiasts different coun tries Preben would like US fliers participate too team South Bay club got serious thinking stage couldnt quite man age trip 89 Maybe next year Isnt wonderful have hobby/sport can travel almost country world welcomed instant friends identical interests Prebens letter ended up 40 contestants coun tries spread Iceland Israel almost everything between came Switzer land Bavaria Berlin Westphalia Osnabruck area England Scotland Norway Nic Wright England won again Denmark took team trophy followed England NorIv finest model building equipment manufactured kahe4 zfloS4loAuh1wi 4ohrk a41/i/nna 94eady& Mdc dealer order direct-500A Magic Magnet Builder Icontains 16x48 Steel Base Plate 30 Magnets 10 stands S 9450 SOOB Master Magic Magnet Builder Icontains 1 6x4B Steel base plate 60 Magnets 20 stands 10 Vert press 10 steps 20 rib holders 50 sets nuts & bolts$16895 503B Base Plate Extension 1 6x1 6 Steel Base plate building giants$ 2695 501A Unassembled Magnets 10 pak$ 1195 501 B Assembled Magnets 10 pakS 2200 502 Stands 110 uprights primarily fuselage easyS 950 504 Vertical press 5 pak holding spars leading trailing edges position$ 995 505 Steps 5 pakl adjustible leading & trailing edge positioning$ 595 506 Rib Holder 10 pak Use magnet building faster$ 995 ~TUFELDON J LIND COMPANY 3151 Caravelle Dr Lake Havasu City AZ 86403 C 16021453 7970 Send sell addressed stamped envelope catalog ot products M/C & Visa accepted December 1989 45 Fourmost Fuselage Fixture Mark II Fourmost Fuselage Fixture Mark II designed auto matically align fuselage structures built strings measuring eyeballing Price $5995 Simply slide four centering brackets track until align fire wall tail joint two bulkheads Clamp fuselage together lightly rubber bands structure will straight ready gluing Fixture will accomodate fuselages long four feet wide eight inches eight inches Please include $400 br Shipping Handling direct orders FOURMOST PRODUCTS 4040 24TH AVEFOREST GROVE OR 971165031 357-2732 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NiCd Batteries Ihe chargers YOU need packageFor Cycier-Chargec,,,, $23996 Fits 48V Rs 96V Tx packsPlus ened Ceii Others avaable write kier.. *3495Reguiar Modei $4696 ForPlus $3 S&H\ eiFor held kit smatPlus $3 S&H tipleelectric boat batteriesSpecify 612 24V Heavy Duty Model.. $5896 sport winch large boat andPlus $4 S&H electric power charging batteriesSpecify 6 1 2V CaRa Products ox 221 DealerinqurneslnveedCanton SO 57013 pp THERMAL CHARGER what looking electric sailplane good looks easy build fun fly great performance Thermal Charger Wing Span Wing Area Motor Included 60 Inches 545 Sq Inches Leisure 05 Electric C — t PRECISION PRODUCTS INC 714 592-5144 510 E Arrow Highway San Dimas CA 91773 way first day just little wind ran practice round let fliers prac tice own afterwards needed especially Alps because unfamiliar seaside slopes winds second day shot four good contest rounds fairly good west wind third day rather weak winds did round Some fliers went sight seeing some stayed practice fourth day expected good north winds finally arrived 12- 20-mph winds directly best slope made five rounds dinner delayed until 800 pm Rain forecast next day turned out expectedan off day kept people busy think happy time Evening entertainment included RoIf Girs berger designer RG series airfoils new Chairman FAI s F3B ClAM Subcom mitteeBB telling about airfoil develop ments showing Selig-Donovan Princeton wind tunnel video several times very popular conference about F3F rules future Viking Races took two hours de cide rules great meet again Derbyshire England October 1990 RoIf also showed two films about modeling full-scale gliding Switzerland 1942-44 100% professionally done included some unique things films original purpose PR Swiss Army Air Force long rainy day off Chas Gardner Brian Sharp England Scotland told about British Slope Cross-Country Racing ended 20-minute presentations six interesting thought planes entered contest pilots plus sometimes interpre ter Very popular too course pilots se lected very proud have opportunity tell about marvelous designs 'Then time get dressed banquetand long happy night special Viking Year award went Siegfried Schedel Bavaria Siegfried started out looking very much like beginner F3F practiced minute could find climbed steadily scoreboard ended fifth place beating 80% winning Danish team agreement best man won no protests during contest Includ ing practice must have close 1000 flights two three models minor damage landings com pletely repaired hour 'The next morning everybody packed went home again Anna Johannes owners Vigso Bugt Pension everyone stayed BB happy too said never better guests wished us come back soon hope will have success new American Sportsman F3B class dont know told fact F3B contests Denmark according local Sportsman rules far biggest problem num ber officials needed So decided cut down simply taking five steps 1 Eliminating Distance task altogether 2 Fly Duration task individual flights after another no group scoring 3 No working-time slots 4 Organizer-supplied winches 5 Only attempt flight tough pop off Its far simpler contest run because everybody can help another same way normal American Duration-only contest challenge airthe six-minute Preci sion Speed runis exactly same real F3B course guys would have liked fly Distance no way can make work Three weeks ago ran National Cham pionship F3B have separate Nats classes F3A F3B F3C etc 18 pi lots zero officials fixed se quence flying timekeeping flagging etc CD himself managed place second course way setting up will produce some breaks since people active time lunch break must put managed seven rounds two days including early dinner Sunday night Italian pizza res taurant everyone 15 50 years great fun Next weekend will busy practicing F3B team Paris Preben Danish teams managerBB have good team time mean have some bright young people team gonna win anything down Paris certainly will middle time team does have strongest men eitherthe members spread second tOth place Nats will survive physi cally mentally hope will learn some thing can used Czechoslovakia next year 1990 European F3B Championships Netherlands -1991 F3B World Championships Only has made Speed task better 18 seconds official contest dont count practice runs arrive Paris day before practice round would have liked few days 46 Model Aviation durable skis made lightweight aluminum feature steel spring holds ski rigid flight also elevates axle above ski no modifications cur rent gear wire needed can go wheels skis seconds side ski also has special edge allows excellent tracking icy surfaces avalisbie three sizes snd can purchased trikes just mains order please send check money order $200 shipping handling Add 8% sales tax Minnesota Allow 2 weeks delivery large scales please submit weight wing span Telephone inquires call Ron 612-781-7333 NORTHERN 20 30 Trike $2000 Mains $1500 MODELING 40 60 Trike $2200 Mains $1700 PRODUCTS Large Scale Trike $7500 Mains $5500 PO Box 21181 ColumbIa Heights MN 55421 781-7333 DIAMOND ShARPENS BLADES NA JIFFY GET GREAT EDGE ON THAT NO11 OR UBER SKIVER BLADE COMES WITH REVERSIBLE BLOCK 325 grit 1000 grit $1500 Replacement Block$850 ADD $175 P&H 6% sales tax CA AVAILABLE CERAMIC AND ARKANSAS WHETSTONES P 0. BOX 8 MOORPARK CA 93020 805 529-9313 short money time again Prebens letters always fun read full good information great time Preben 1987 following Osnabruck F3B World Champs staying same pension flying same slopes talked ahout wind north-facing bluff high above beach cant imagine finer place Slope flying once wrote bluff must 400 ft high Preben later called attention fact highest spot Denmark 350 ft still say looked high time remarks about fly F3B con tests could food thought US CDs run ning Sportsman multitask events Because no hard-and-fast rules can run SMT contests way makes sense local conditions Wingspan winch launches windspeed Wisconsins Lee Murray kind enough write share some interesting data proj ect has working Back 1986 several Sailplane fliers club began collect records flights IIIBTBI2IIN 11$ ELIcIT tITlES PndlgJ II HIngE. 33-3344-1346-774 Ill MItag learn about performance various mod els effects flying conditions etc records now include over 250 flights provide some insight flight performance related windspeed launch methods Sailplane type Virtually flights club field sod farm often damp compared higher ground evaporative cooling often limits thermal generation Location would important consideration comparing results tween clubs Winch launches using Two-Meter Prodi gy resulted flights 25 seconds longer av erage high-start widely recognized difference performance between wingspans also evident shown chart below AWRACE FLIGHT TIME VT HIIECSPHN 336 FlIght Histopa ii isA N1a Aa 3p 4 TIHH IN iI121IN146SB WII4GNFBS PPndlgyB 50-4 B CopiloA comparison theoretical flight times suggests effect involves differ ences sink rate difference between 2M Standard class 78 vs 100 larger difference between Standard Unlim ited Class 2M class RO-8 has old standby years E-205 wing pro file substituted performer Prodigy shows up also Flying moderate wind does decrease flight times based Prodigy flying off highstart chart titled Flight Times vs Windspeed shows relationshipwhich fact undoubtedly linear lack data shown linear Flight lAment WinO Spa. Pndlns-IhIhnlapt Sa N6 Ia N 3 lend Spend reason flight times appear correlated windspeed probably related getting height launches since winch flights did show same correlation Model & Average Flight Times Minutes 2-Meter Prodigy RO-8 Std Class Cumic XC/Unlimited Dynasoar Scale ASW-17 526 465 891 1022 428 As know am big advocate theoreti cal Sailplane performance analysis Lee John Hohensee developed market computer Sail plane design/analysis programs called PC-Soar MaxSoar BB Part quest tie theory reality analysis actual flight per formance Al Scidmore Professor Electrical Engineering University Wisconsin pursuing instrumentation Sailplane digital data logger hope someday ALL STAINLESS STEEL HEAD LITE IItm BEST GLOW PLUG CONNECTOR Stainless Steel HEAD LOCK BEST DESIGN Welded No Solder Acid Flux Flexing Wires BEST NiCad Field Replaceable 12 AH SANYO 15 AH PANASONIC BEST QUALITY & GUARANTEE MODEL PRODUCTS CORPORATION BEST PRICESt #045-WIO NiCad Charger$ 995 available write directSt #040-With NiCad$ 1595 add $100 $200 outside US St #041-With NiCad & Charger $ 2595 MODEL PRODUCTS CORP PO Box 100 Allamuchy NJ 07820 201850-1508 December 1989 47 will able share some hard numbers Sailplane performance have calibration data first versions altimeter temperature sensor sup ply voltage monitor velocity sensor Al has some improvements under way altitude velocity Tbe equipment will small enough fit inside X-Country Scale ships can mounted pod above wing smaller models would nice transmit digitally encoded data ground someone would like get involved would love bear him Presently sensor outputs 0-20 VDC Drop line Lee Murray 1300 Bay Ridge Road Appleton WI 54915 phone 1-414/7314848 Lees letter reminder its good idea keep logbook Gliders Person ally usually dont note time flight enter date place number flights windspeed flying conditions weight ballast used results changes trim reason recording flight times during prac tice session maximum time launch objective Practice occasion perfecting pre cision landing one-minute countdown trying out different thermaling techniques general doing wild crazy things dont dare try during contest Id like review about practice sessions future column Please write youd like share favorite meth ods How-to-make-molds video previously re viewed two Julian Tamezs instructional videos titled Vacuum Bag Cut ting Foam Cores Now Ive chance see Julians 34-hr tape called Making Fiberglass Molds Let tell theres lot informa tion Julian partner Greg Norsworthy go through process making fiberglass fuse lage Cross-Country ship start making plug making fiberglass molds finally laying up two halves fu selage joining together whole pro cess takes good deal time involves lot skill tricks trade As Julian says tape gives ABCs making molds what equipment materials will need manufacture kind fiber glass part have idea youd like make own F/G fuselages guarantee studying tape will save much time aggravation kept returning thought watching Guys like Bob Sealy Jerry Slates really earn money make nice fuselages such reasonable prices three Julians tapes $3495 less 20% NSS LSF members plus $350 shipping address Channel Productions 19827 Bishops Gate Suite No1 Humble TX 77338 Phone 1-713/443-1253 days 5403944 evenings Sportsman Multi-Task update winner isMark Allens Falcon 880 course Im re ferring Jim Grays RIC Soaring Digest Chal lenge Design contest Sportsman Multi-Task SMT Sailplanes very interesting competition because good de signs entered including several brand-new ones says Soaring lacking new exciting things days addition winning Falcon 880 featured October column other designs en tered alphabetical order Bob Dodgsons Camano Terry Edmonds Callisto Don Chan ceys Conquest Don Edbergs Hustler Jeremy Teos Odyssey Bob Sealys Pulsar Paul Carlsons Quasoar Max Mills Westwind Sportsman Multi-Task new contest con cept Its takeoff F3B Duration/Distance Speed task flying restricted aircraft simplified flexible contest operation SMT suitable intermediate-level fliers say about LSF Level 3 designed middle ground between AMA Thermal Duration flying real International F3B Soaring competi tion limitation maximum weight SMT planes intended keep Gliders nonintim idating Sportsman-level fliers Thermal Duration will always bedrock Soaring USA youll find addi tion some Distance Speed tasks just adds fun makes quite different ball game Sailplane fliers say looking something new challenging think SMT will provide excitement seek ing restriction SMT planes must weigh 75 oz ballast pretty well excludes F3B planes permits just about kits market plus original de signs approximately two-meter 115-inspan size range Now suggested SMT contest rules place see October column have de sign RCSD jury feels good plane event next step clubs around coun try try SMT contests practice sessions see works club has run Distance Speed tasks before first problem will making 3 New ARFs ZMP SUKHOI Su-26M 1/5 ScaleIMPALA Masters Pattern span 68 area 890 sq motor 4 stroke 120 equivspan 66 area 800 sq motor 4 stroke 120 60 rear Preassembled lightweight epoxy fuselage sheeted plug-in wingsPresssembled balsa fuselage veneersd plug-in wings 8 stabs sheeted stab fin & rudder 5 dia epoxy cowl texan canopy &Epoxy cowl pipe cover removable canopy Illustrated illustrated assembly manualassembly manual see hobby dealer order direct MONARCH AMA Sport Pattern span 66 area 750 sq motor 4 stroke 90 60 Cu Preassembled balsa fuselage venesred wing shaped balsa parts texan canopy epoxy cowl illustrated assembly manual c ZIMPRO MARKETING tu sOt arK OAK StOOL 55 35535 P001St 515 482 6155 48 Model Aviation AIR WOLF EPOXY FIBERGLASS FUSELAGES TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $21000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 Z ial Introductory Offer Frequency Conversion $3500 Includes Crystals Certification Special Fast Turnaround Now Available CALL Send Large Self Addressed Envelope Brochures UPS U S Mail Federai Express Used Mastercard Visa Accepted pair sighting devices used define two dimensionless planes 150 meters apart known Base Base B two bases just big windows sky delineate distance Glid ers need fly leg Speed Distance circuit RMSA PPSS clubs Colorado fly quite bit Distance club contests weve found hoop-on-a-tripod sighting device both simple make easy use first described Dan Pruss June 1983 Soaring column thismagazine dont save old sues MA send business-size envelope 25C stamp Ill return reprint Dans column showing make sighting device quick description Pruss sighting device 36-in length %2 music wire stuck holes drilled opposite sides plastic like Lucite metal block about 15 20 side A-in hole drilled precisely 900 %2 holes Through hole inserted 10in length A-in-GD brass tube bottom block drilled No 7 drill tapped x 20 attachment camera tripod operation set up sighting device near winches Base walk 150 meters upwind F3B crosswind AMA rules set down other sighting device Base B just look through brass tube sight Base device adjust ing head tripod Doing same thing Base Aie sighting Base B deviceguarantees wire hoops both bases exactly parallel other Necking down end brass tubes soldering short pieces two-nextsmaller-size tubes makes sighting process precise look through big end 150-meter distance can laid out measured length cable fishing leader stored fast-wind spool Just play out walk Base B wind up walk back whole procedure can done faster setting out winch Speed task run flier time flagger required Base B flag ger puts up flag Glider about half way Base B drops Glider breaks plane defined wire hoop flag must stay up Glider fails break planeie cuts turnso pilots timer can tell him go back try again timer usually calls Base turns pilot pilot needs stand near timer Base sighting device practice its best pilot get lined up Base can judge turn himself instead waiting Turn call Distance task usually run four pi lots flying man-on-man although can done time small contests needs flagger differently colored flag Base B plane four planes per heat youll need flaggers red white blue green colored flags course need establish before launching color signed pilot Holding up red white blue green flag also holding up Glider helps Base B crew determine plane flag Also weve found inex pensive Radio Shack-type two-way radio set very helpful communicating back forthISO meters just bit too far shouting As mentioned above first time two flying SMT need called contest Its good schedule couple practice sessions everyone gets hang flying Speed Distance tasks well getting accustomed flagging jobs Give try Please let know works out Airfoils Low Speeds title 398-page book Michael Selig John Donovan Da vid Fraser reporting long-awaited results tests using Princeton Universitys lowspeed wind tunnel book being published Herk Stokely Soartech #8 sells $20 ppd may order now Herk 1504 Horseshoe Drive Virginia Beach VA 23451 Princeton tests probably exten sive best controlled investigation model Sailplane airfoils ever done As such Sailplaners have extremely anxious read about what Michael John Dave have discoveredand some new super airfoils will forthcoming So Soartech #8 should very interesting popular read David Fraser also designer popular Sailplane Design computer program lat est Version 30 has Princeton data cludes 87 airfoils including flapped tripped versions David says Its quite gold Version 30 sells $35 Version 2 users can updated 30 returning diskette $10 Write Sailplane Design 1335 Slaton Dr Maple Glen PA 19002 Torrey Pines Scale Fun Fly Its short notice over Thanksgiving weekend Friday through Sunday Torrey Pines Gulls club will put Scale-only Slope Fun Fly fa mous Torrey Pines site just north San Diego Charley Morrey Slope Soaring News wrote invite Scale fans come fly Charley said details hadnt nailed Continued page 156 December 1989 49 Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royal Tower Hobbies World Engines Spectrum Analyzers CalIbrated Test Instruments Large Inventory RIC Parts Crystals THE PIPER BRAVE scale model Pipers latest Ag plane t wing span 30-33 lbs 5 cc power lb payload ational flaps hopper door onal Spreader Kit formed aluminum landing gear rglass cowls um-formed canopy tucted extruded foam ply hardwood E $269~ OPTIONAL $ 4fl95 Smoker l actually dusting KITSPREADER SEND $100 FOR CATALOG OFQ 4/RT 1 NEODESHA KS 66757 SAC KITS AND ACCESSORIES316 325-2821 Free Shipping Kit OrdersScott Airplane CompanyVISA/MASTERCARD GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation
Edition: Model Aviation - 1989/12
Page Numbers: 44, 45, 46, 47, 48, 49, 156
NEAT constant-tension winch Jack Perecman Golden Valley MN sent excellent photos very neat winch Jacks letter tells about Enclosed will find some photos showing constant-tension winch designed built winch presently its second season far has proven quite reliable Im mem ber Minnesota RC Soaring Society have used winch both club fun-flys contests motor starter motor Johnson outboard has high torque plus ad vantages both long shaft thread end splines near motor face make mounting drum quite easy photo shows winch turnaround transportation mode Another photos shows right side winch its operating position wheels have flipped out underneath frame now resting ground foot treadle behind attached winch means bicycle brake cable operation farther treadle pushed down greater tension line T handle device top battery emer gency kill switch threaded rod crank low motor pivots motor/drum assembly fine adjustment line level winding final photo shows main parts constant-tension device Pushing down foot treadle pulls cable causes switch arm pivot counterclockwise away spring-loaded roller arms microswitch normally closed As soon switch pulled away roller arms closes en ergizes solenoid supplies power motor As tension line increases roller arms begin pivot toward switch ten sion line counterbalanced two springs desired tension achieved left roller arm touches microswitch open ing turning off solenoid will stay off until tension line decreases greater tension desired operator pushes foot treadle down pulls switch farther away roller arm springs have stretched before arm contacts switch operation due dampening effect stretch line way device automatically pulses motor off very similar what operator would using normal foot switch Other features include one-way clutch roller can engaged disengaged moving 44 Model Aviation Radio Control Soaring Byron Blakeslee 3134 N Winnebago Dr Sedalia CO 80135 Four Ts Teutonic Tailless Terror Team Germany flew Viking Cup Slope Races held Denmark Note models has some sort experimental aftmounted horizontal stability augmentation surface model just front has extended fu selage central fin other wings use tip-mounted fins Photo Preben Norhoim Swiss team Viking Cup meet Manager RoIf Gersberger right Norholm Jack Perecman designed winch its constant-tension mechanism Motor starter Johnson outboard motor Jack en gineer 3M company designs sort thing living Items note T-handled kill switch mounted right bat tery terminal extra-heavy battery post clamps flip-up wheel carriage Foot treadle gas pedal tells winch much tension put towline winch motor cycles automatically maintain desired tension Author Blakeslee has info column small black lever seen just above center shaft clutch roller uses Torrington oneway roller bearing addition just below roller mounted roller arm small tri angular piece urethane rubber rubs rim drum effectively brakes drum slightly prevent backlashes main purpose building winch first see simple reliable constant-tension device could built F3B competition days weak link Second perhaps applicable average club putting stop switch arm possible easily ad just maximum tension pilot can achieve using winch have able launch Gnome hand-launched Glider immediately readjust winch launching Windsong addition possible beginners have con fidence launching airplanes fear folding wings can see what beautiful job engineering fabricating Jack did winch especially constant-tension device CT mechanism would course work winch just Jacks outboard-motor design Some careful machinework would need done duplicate though Jack said hed make drawings avail able theres enough interest can con tact Jack Pereeman 224 Natchez Ave North Golden Valley MN 55422 Incidenially winches should have kill switch similar Jacks cut off battery power case emergency common situ ation stuck solenoid tries strain plane through turnaround need switch can operate quickly state severe panic RV shops sell big copper knife switches about $20 mount right battery post Theyre cheap insurance Danish connection risk infringing Mark Triebes turf Id like print letter friend Preben Norholm Copenhagen describing 1989 Viking Cup Race Vi king Cup biggest annual International F3F event held North Sea slopes near Hanstholm Denmark last June F3F FAI Provisional event Slope Racers fly 10 laps 100-meter course against clockone plane time Slope Racing US traditionally run exciting way te wtth four planes flying against other heat However Europeans decided certain prospect midair collisions consequent loss hundreds dollars worth planes equipment sufficient rea son race one-at-a-time Preben founders F3F Racing justifiably proud success Viking Cup has achieved Preben too beauty event like gathering gether enthusiasts different coun tries Preben would like US fliers participate too team South Bay club got serious thinking stage couldnt quite man age trip 89 Maybe next year Isnt wonderful have hobby/sport can travel almost country world welcomed instant friends identical interests Prebens letter ended up 40 contestants coun tries spread Iceland Israel almost everything between came Switzer land Bavaria Berlin Westphalia Osnabruck area England Scotland Norway Nic Wright England won again Denmark took team trophy followed England NorIv finest model building equipment manufactured kahe4 zfloS4loAuh1wi 4ohrk a41/i/nna 94eady& Mdc dealer order direct-500A Magic Magnet Builder Icontains 16x48 Steel Base Plate 30 Magnets 10 stands S 9450 SOOB Master Magic Magnet Builder Icontains 1 6x4B Steel base plate 60 Magnets 20 stands 10 Vert press 10 steps 20 rib holders 50 sets nuts & bolts$16895 503B Base Plate Extension 1 6x1 6 Steel Base plate building giants$ 2695 501A Unassembled Magnets 10 pak$ 1195 501 B Assembled Magnets 10 pakS 2200 502 Stands 110 uprights primarily fuselage easyS 950 504 Vertical press 5 pak holding spars leading trailing edges position$ 995 505 Steps 5 pakl adjustible leading & trailing edge positioning$ 595 506 Rib Holder 10 pak Use magnet building faster$ 995 ~TUFELDON J LIND COMPANY 3151 Caravelle Dr Lake Havasu City AZ 86403 C 16021453 7970 Send sell addressed stamped envelope catalog ot products M/C & Visa accepted December 1989 45 Fourmost Fuselage Fixture Mark II Fourmost Fuselage Fixture Mark II designed auto matically align fuselage structures built strings measuring eyeballing Price $5995 Simply slide four centering brackets track until align fire wall tail joint two bulkheads Clamp fuselage together lightly rubber bands structure will straight ready gluing Fixture will accomodate fuselages long four feet wide eight inches eight inches Please include $400 br Shipping Handling direct orders FOURMOST PRODUCTS 4040 24TH AVEFOREST GROVE OR 971165031 357-2732 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NiCd Batteries Ihe chargers YOU need packageFor Cycier-Chargec,,,, $23996 Fits 48V Rs 96V Tx packsPlus ened Ceii Others avaable write kier.. *3495Reguiar Modei $4696 ForPlus $3 S&H\ eiFor held kit smatPlus $3 S&H tipleelectric boat batteriesSpecify 612 24V Heavy Duty Model.. $5896 sport winch large boat andPlus $4 S&H electric power charging batteriesSpecify 6 1 2V CaRa Products ox 221 DealerinqurneslnveedCanton SO 57013 pp THERMAL CHARGER what looking electric sailplane good looks easy build fun fly great performance Thermal Charger Wing Span Wing Area Motor Included 60 Inches 545 Sq Inches Leisure 05 Electric C — t PRECISION PRODUCTS INC 714 592-5144 510 E Arrow Highway San Dimas CA 91773 way first day just little wind ran practice round let fliers prac tice own afterwards needed especially Alps because unfamiliar seaside slopes winds second day shot four good contest rounds fairly good west wind third day rather weak winds did round Some fliers went sight seeing some stayed practice fourth day expected good north winds finally arrived 12- 20-mph winds directly best slope made five rounds dinner delayed until 800 pm Rain forecast next day turned out expectedan off day kept people busy think happy time Evening entertainment included RoIf Girs berger designer RG series airfoils new Chairman FAI s F3B ClAM Subcom mitteeBB telling about airfoil develop ments showing Selig-Donovan Princeton wind tunnel video several times very popular conference about F3F rules future Viking Races took two hours de cide rules great meet again Derbyshire England October 1990 RoIf also showed two films about modeling full-scale gliding Switzerland 1942-44 100% professionally done included some unique things films original purpose PR Swiss Army Air Force long rainy day off Chas Gardner Brian Sharp England Scotland told about British Slope Cross-Country Racing ended 20-minute presentations six interesting thought planes entered contest pilots plus sometimes interpre ter Very popular too course pilots se lected very proud have opportunity tell about marvelous designs 'Then time get dressed banquetand long happy night special Viking Year award went Siegfried Schedel Bavaria Siegfried started out looking very much like beginner F3F practiced minute could find climbed steadily scoreboard ended fifth place beating 80% winning Danish team agreement best man won no protests during contest Includ ing practice must have close 1000 flights two three models minor damage landings com pletely repaired hour 'The next morning everybody packed went home again Anna Johannes owners Vigso Bugt Pension everyone stayed BB happy too said never better guests wished us come back soon hope will have success new American Sportsman F3B class dont know told fact F3B contests Denmark according local Sportsman rules far biggest problem num ber officials needed So decided cut down simply taking five steps 1 Eliminating Distance task altogether 2 Fly Duration task individual flights after another no group scoring 3 No working-time slots 4 Organizer-supplied winches 5 Only attempt flight tough pop off Its far simpler contest run because everybody can help another same way normal American Duration-only contest challenge airthe six-minute Preci sion Speed runis exactly same real F3B course guys would have liked fly Distance no way can make work Three weeks ago ran National Cham pionship F3B have separate Nats classes F3A F3B F3C etc 18 pi lots zero officials fixed se quence flying timekeeping flagging etc CD himself managed place second course way setting up will produce some breaks since people active time lunch break must put managed seven rounds two days including early dinner Sunday night Italian pizza res taurant everyone 15 50 years great fun Next weekend will busy practicing F3B team Paris Preben Danish teams managerBB have good team time mean have some bright young people team gonna win anything down Paris certainly will middle time team does have strongest men eitherthe members spread second tOth place Nats will survive physi cally mentally hope will learn some thing can used Czechoslovakia next year 1990 European F3B Championships Netherlands -1991 F3B World Championships Only has made Speed task better 18 seconds official contest dont count practice runs arrive Paris day before practice round would have liked few days 46 Model Aviation durable skis made lightweight aluminum feature steel spring holds ski rigid flight also elevates axle above ski no modifications cur rent gear wire needed can go wheels skis seconds side ski also has special edge allows excellent tracking icy surfaces avalisbie three sizes snd can purchased trikes just mains order please send check money order $200 shipping handling Add 8% sales tax Minnesota Allow 2 weeks delivery large scales please submit weight wing span Telephone inquires call Ron 612-781-7333 NORTHERN 20 30 Trike $2000 Mains $1500 MODELING 40 60 Trike $2200 Mains $1700 PRODUCTS Large Scale Trike $7500 Mains $5500 PO Box 21181 ColumbIa Heights MN 55421 781-7333 DIAMOND ShARPENS BLADES NA JIFFY GET GREAT EDGE ON THAT NO11 OR UBER SKIVER BLADE COMES WITH REVERSIBLE BLOCK 325 grit 1000 grit $1500 Replacement Block$850 ADD $175 P&H 6% sales tax CA AVAILABLE CERAMIC AND ARKANSAS WHETSTONES P 0. BOX 8 MOORPARK CA 93020 805 529-9313 short money time again Prebens letters always fun read full good information great time Preben 1987 following Osnabruck F3B World Champs staying same pension flying same slopes talked ahout wind north-facing bluff high above beach cant imagine finer place Slope flying once wrote bluff must 400 ft high Preben later called attention fact highest spot Denmark 350 ft still say looked high time remarks about fly F3B con tests could food thought US CDs run ning Sportsman multitask events Because no hard-and-fast rules can run SMT contests way makes sense local conditions Wingspan winch launches windspeed Wisconsins Lee Murray kind enough write share some interesting data proj ect has working Back 1986 several Sailplane fliers club began collect records flights IIIBTBI2IIN 11$ ELIcIT tITlES PndlgJ II HIngE. 33-3344-1346-774 Ill MItag learn about performance various mod els effects flying conditions etc records now include over 250 flights provide some insight flight performance related windspeed launch methods Sailplane type Virtually flights club field sod farm often damp compared higher ground evaporative cooling often limits thermal generation Location would important consideration comparing results tween clubs Winch launches using Two-Meter Prodi gy resulted flights 25 seconds longer av erage high-start widely recognized difference performance between wingspans also evident shown chart below AWRACE FLIGHT TIME VT HIIECSPHN 336 FlIght Histopa ii isA N1a Aa 3p 4 TIHH IN iI121IN146SB WII4GNFBS PPndlgyB 50-4 B CopiloA comparison theoretical flight times suggests effect involves differ ences sink rate difference between 2M Standard class 78 vs 100 larger difference between Standard Unlim ited Class 2M class RO-8 has old standby years E-205 wing pro file substituted performer Prodigy shows up also Flying moderate wind does decrease flight times based Prodigy flying off highstart chart titled Flight Times vs Windspeed shows relationshipwhich fact undoubtedly linear lack data shown linear Flight lAment WinO Spa. Pndlns-IhIhnlapt Sa N6 Ia N 3 lend Spend reason flight times appear correlated windspeed probably related getting height launches since winch flights did show same correlation Model & Average Flight Times Minutes 2-Meter Prodigy RO-8 Std Class Cumic XC/Unlimited Dynasoar Scale ASW-17 526 465 891 1022 428 As know am big advocate theoreti cal Sailplane performance analysis Lee John Hohensee developed market computer Sail plane design/analysis programs called PC-Soar MaxSoar BB Part quest tie theory reality analysis actual flight per formance Al Scidmore Professor Electrical Engineering University Wisconsin pursuing instrumentation Sailplane digital data logger hope someday ALL STAINLESS STEEL HEAD LITE IItm BEST GLOW PLUG CONNECTOR Stainless Steel HEAD LOCK BEST DESIGN Welded No Solder Acid Flux Flexing Wires BEST NiCad Field Replaceable 12 AH SANYO 15 AH PANASONIC BEST QUALITY & GUARANTEE MODEL PRODUCTS CORPORATION BEST PRICESt #045-WIO NiCad Charger$ 995 available write directSt #040-With NiCad$ 1595 add $100 $200 outside US St #041-With NiCad & Charger $ 2595 MODEL PRODUCTS CORP PO Box 100 Allamuchy NJ 07820 201850-1508 December 1989 47 will able share some hard numbers Sailplane performance have calibration data first versions altimeter temperature sensor sup ply voltage monitor velocity sensor Al has some improvements under way altitude velocity Tbe equipment will small enough fit inside X-Country Scale ships can mounted pod above wing smaller models would nice transmit digitally encoded data ground someone would like get involved would love bear him Presently sensor outputs 0-20 VDC Drop line Lee Murray 1300 Bay Ridge Road Appleton WI 54915 phone 1-414/7314848 Lees letter reminder its good idea keep logbook Gliders Person ally usually dont note time flight enter date place number flights windspeed flying conditions weight ballast used results changes trim reason recording flight times during prac tice session maximum time launch objective Practice occasion perfecting pre cision landing one-minute countdown trying out different thermaling techniques general doing wild crazy things dont dare try during contest Id like review about practice sessions future column Please write youd like share favorite meth ods How-to-make-molds video previously re viewed two Julian Tamezs instructional videos titled Vacuum Bag Cut ting Foam Cores Now Ive chance see Julians 34-hr tape called Making Fiberglass Molds Let tell theres lot informa tion Julian partner Greg Norsworthy go through process making fiberglass fuse lage Cross-Country ship start making plug making fiberglass molds finally laying up two halves fu selage joining together whole pro cess takes good deal time involves lot skill tricks trade As Julian says tape gives ABCs making molds what equipment materials will need manufacture kind fiber glass part have idea youd like make own F/G fuselages guarantee studying tape will save much time aggravation kept returning thought watching Guys like Bob Sealy Jerry Slates really earn money make nice fuselages such reasonable prices three Julians tapes $3495 less 20% NSS LSF members plus $350 shipping address Channel Productions 19827 Bishops Gate Suite No1 Humble TX 77338 Phone 1-713/443-1253 days 5403944 evenings Sportsman Multi-Task update winner isMark Allens Falcon 880 course Im re ferring Jim Grays RIC Soaring Digest Chal lenge Design contest Sportsman Multi-Task SMT Sailplanes very interesting competition because good de signs entered including several brand-new ones says Soaring lacking new exciting things days addition winning Falcon 880 featured October column other designs en tered alphabetical order Bob Dodgsons Camano Terry Edmonds Callisto Don Chan ceys Conquest Don Edbergs Hustler Jeremy Teos Odyssey Bob Sealys Pulsar Paul Carlsons Quasoar Max Mills Westwind Sportsman Multi-Task new contest con cept Its takeoff F3B Duration/Distance Speed task flying restricted aircraft simplified flexible contest operation SMT suitable intermediate-level fliers say about LSF Level 3 designed middle ground between AMA Thermal Duration flying real International F3B Soaring competi tion limitation maximum weight SMT planes intended keep Gliders nonintim idating Sportsman-level fliers Thermal Duration will always bedrock Soaring USA youll find addi tion some Distance Speed tasks just adds fun makes quite different ball game Sailplane fliers say looking something new challenging think SMT will provide excitement seek ing restriction SMT planes must weigh 75 oz ballast pretty well excludes F3B planes permits just about kits market plus original de signs approximately two-meter 115-inspan size range Now suggested SMT contest rules place see October column have de sign RCSD jury feels good plane event next step clubs around coun try try SMT contests practice sessions see works club has run Distance Speed tasks before first problem will making 3 New ARFs ZMP SUKHOI Su-26M 1/5 ScaleIMPALA Masters Pattern span 68 area 890 sq motor 4 stroke 120 equivspan 66 area 800 sq motor 4 stroke 120 60 rear Preassembled lightweight epoxy fuselage sheeted plug-in wingsPresssembled balsa fuselage veneersd plug-in wings 8 stabs sheeted stab fin & rudder 5 dia epoxy cowl texan canopy &Epoxy cowl pipe cover removable canopy Illustrated illustrated assembly manualassembly manual see hobby dealer order direct MONARCH AMA Sport Pattern span 66 area 750 sq motor 4 stroke 90 60 Cu Preassembled balsa fuselage venesred wing shaped balsa parts texan canopy epoxy cowl illustrated assembly manual c ZIMPRO MARKETING tu sOt arK OAK StOOL 55 35535 P001St 515 482 6155 48 Model Aviation AIR WOLF EPOXY FIBERGLASS FUSELAGES TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $21000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 Z ial Introductory Offer Frequency Conversion $3500 Includes Crystals Certification Special Fast Turnaround Now Available CALL Send Large Self Addressed Envelope Brochures UPS U S Mail Federai Express Used Mastercard Visa Accepted pair sighting devices used define two dimensionless planes 150 meters apart known Base Base B two bases just big windows sky delineate distance Glid ers need fly leg Speed Distance circuit RMSA PPSS clubs Colorado fly quite bit Distance club contests weve found hoop-on-a-tripod sighting device both simple make easy use first described Dan Pruss June 1983 Soaring column thismagazine dont save old sues MA send business-size envelope 25C stamp Ill return reprint Dans column showing make sighting device quick description Pruss sighting device 36-in length %2 music wire stuck holes drilled opposite sides plastic like Lucite metal block about 15 20 side A-in hole drilled precisely 900 %2 holes Through hole inserted 10in length A-in-GD brass tube bottom block drilled No 7 drill tapped x 20 attachment camera tripod operation set up sighting device near winches Base walk 150 meters upwind F3B crosswind AMA rules set down other sighting device Base B just look through brass tube sight Base device adjust ing head tripod Doing same thing Base Aie sighting Base B deviceguarantees wire hoops both bases exactly parallel other Necking down end brass tubes soldering short pieces two-nextsmaller-size tubes makes sighting process precise look through big end 150-meter distance can laid out measured length cable fishing leader stored fast-wind spool Just play out walk Base B wind up walk back whole procedure can done faster setting out winch Speed task run flier time flagger required Base B flag ger puts up flag Glider about half way Base B drops Glider breaks plane defined wire hoop flag must stay up Glider fails break planeie cuts turnso pilots timer can tell him go back try again timer usually calls Base turns pilot pilot needs stand near timer Base sighting device practice its best pilot get lined up Base can judge turn himself instead waiting Turn call Distance task usually run four pi lots flying man-on-man although can done time small contests needs flagger differently colored flag Base B plane four planes per heat youll need flaggers red white blue green colored flags course need establish before launching color signed pilot Holding up red white blue green flag also holding up Glider helps Base B crew determine plane flag Also weve found inex pensive Radio Shack-type two-way radio set very helpful communicating back forthISO meters just bit too far shouting As mentioned above first time two flying SMT need called contest Its good schedule couple practice sessions everyone gets hang flying Speed Distance tasks well getting accustomed flagging jobs Give try Please let know works out Airfoils Low Speeds title 398-page book Michael Selig John Donovan Da vid Fraser reporting long-awaited results tests using Princeton Universitys lowspeed wind tunnel book being published Herk Stokely Soartech #8 sells $20 ppd may order now Herk 1504 Horseshoe Drive Virginia Beach VA 23451 Princeton tests probably exten sive best controlled investigation model Sailplane airfoils ever done As such Sailplaners have extremely anxious read about what Michael John Dave have discoveredand some new super airfoils will forthcoming So Soartech #8 should very interesting popular read David Fraser also designer popular Sailplane Design computer program lat est Version 30 has Princeton data cludes 87 airfoils including flapped tripped versions David says Its quite gold Version 30 sells $35 Version 2 users can updated 30 returning diskette $10 Write Sailplane Design 1335 Slaton Dr Maple Glen PA 19002 Torrey Pines Scale Fun Fly Its short notice over Thanksgiving weekend Friday through Sunday Torrey Pines Gulls club will put Scale-only Slope Fun Fly fa mous Torrey Pines site just north San Diego Charley Morrey Slope Soaring News wrote invite Scale fans come fly Charley said details hadnt nailed Continued page 156 December 1989 49 Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royal Tower Hobbies World Engines Spectrum Analyzers CalIbrated Test Instruments Large Inventory RIC Parts Crystals THE PIPER BRAVE scale model Pipers latest Ag plane t wing span 30-33 lbs 5 cc power lb payload ational flaps hopper door onal Spreader Kit formed aluminum landing gear rglass cowls um-formed canopy tucted extruded foam ply hardwood E $269~ OPTIONAL $ 4fl95 Smoker l actually dusting KITSPREADER SEND $100 FOR CATALOG OFQ 4/RT 1 NEODESHA KS 66757 SAC KITS AND ACCESSORIES316 325-2821 Free Shipping Kit OrdersScott Airplane CompanyVISA/MASTERCARD GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation
Edition: Model Aviation - 1989/12
Page Numbers: 44, 45, 46, 47, 48, 49, 156
NEAT constant-tension winch Jack Perecman Golden Valley MN sent excellent photos very neat winch Jacks letter tells about Enclosed will find some photos showing constant-tension winch designed built winch presently its second season far has proven quite reliable Im mem ber Minnesota RC Soaring Society have used winch both club fun-flys contests motor starter motor Johnson outboard has high torque plus ad vantages both long shaft thread end splines near motor face make mounting drum quite easy photo shows winch turnaround transportation mode Another photos shows right side winch its operating position wheels have flipped out underneath frame now resting ground foot treadle behind attached winch means bicycle brake cable operation farther treadle pushed down greater tension line T handle device top battery emer gency kill switch threaded rod crank low motor pivots motor/drum assembly fine adjustment line level winding final photo shows main parts constant-tension device Pushing down foot treadle pulls cable causes switch arm pivot counterclockwise away spring-loaded roller arms microswitch normally closed As soon switch pulled away roller arms closes en ergizes solenoid supplies power motor As tension line increases roller arms begin pivot toward switch ten sion line counterbalanced two springs desired tension achieved left roller arm touches microswitch open ing turning off solenoid will stay off until tension line decreases greater tension desired operator pushes foot treadle down pulls switch farther away roller arm springs have stretched before arm contacts switch operation due dampening effect stretch line way device automatically pulses motor off very similar what operator would using normal foot switch Other features include one-way clutch roller can engaged disengaged moving 44 Model Aviation Radio Control Soaring Byron Blakeslee 3134 N Winnebago Dr Sedalia CO 80135 Four Ts Teutonic Tailless Terror Team Germany flew Viking Cup Slope Races held Denmark Note models has some sort experimental aftmounted horizontal stability augmentation surface model just front has extended fu selage central fin other wings use tip-mounted fins Photo Preben Norhoim Swiss team Viking Cup meet Manager RoIf Gersberger right Norholm Jack Perecman designed winch its constant-tension mechanism Motor starter Johnson outboard motor Jack en gineer 3M company designs sort thing living Items note T-handled kill switch mounted right bat tery terminal extra-heavy battery post clamps flip-up wheel carriage Foot treadle gas pedal tells winch much tension put towline winch motor cycles automatically maintain desired tension Author Blakeslee has info column small black lever seen just above center shaft clutch roller uses Torrington oneway roller bearing addition just below roller mounted roller arm small tri angular piece urethane rubber rubs rim drum effectively brakes drum slightly prevent backlashes main purpose building winch first see simple reliable constant-tension device could built F3B competition days weak link Second perhaps applicable average club putting stop switch arm possible easily ad just maximum tension pilot can achieve using winch have able launch Gnome hand-launched Glider immediately readjust winch launching Windsong addition possible beginners have con fidence launching airplanes fear folding wings can see what beautiful job engineering fabricating Jack did winch especially constant-tension device CT mechanism would course work winch just Jacks outboard-motor design Some careful machinework would need done duplicate though Jack said hed make drawings avail able theres enough interest can con tact Jack Pereeman 224 Natchez Ave North Golden Valley MN 55422 Incidenially winches should have kill switch similar Jacks cut off battery power case emergency common situ ation stuck solenoid tries strain plane through turnaround need switch can operate quickly state severe panic RV shops sell big copper knife switches about $20 mount right battery post Theyre cheap insurance Danish connection risk infringing Mark Triebes turf Id like print letter friend Preben Norholm Copenhagen describing 1989 Viking Cup Race Vi king Cup biggest annual International F3F event held North Sea slopes near Hanstholm Denmark last June F3F FAI Provisional event Slope Racers fly 10 laps 100-meter course against clockone plane time Slope Racing US traditionally run exciting way te wtth four planes flying against other heat However Europeans decided certain prospect midair collisions consequent loss hundreds dollars worth planes equipment sufficient rea son race one-at-a-time Preben founders F3F Racing justifiably proud success Viking Cup has achieved Preben too beauty event like gathering gether enthusiasts different coun tries Preben would like US fliers participate too team South Bay club got serious thinking stage couldnt quite man age trip 89 Maybe next year Isnt wonderful have hobby/sport can travel almost country world welcomed instant friends identical interests Prebens letter ended up 40 contestants coun tries spread Iceland Israel almost everything between came Switzer land Bavaria Berlin Westphalia Osnabruck area England Scotland Norway Nic Wright England won again Denmark took team trophy followed England NorIv finest model building equipment manufactured kahe4 zfloS4loAuh1wi 4ohrk a41/i/nna 94eady& Mdc dealer order direct-500A Magic Magnet Builder Icontains 16x48 Steel Base Plate 30 Magnets 10 stands S 9450 SOOB Master Magic Magnet Builder Icontains 1 6x4B Steel base plate 60 Magnets 20 stands 10 Vert press 10 steps 20 rib holders 50 sets nuts & bolts$16895 503B Base Plate Extension 1 6x1 6 Steel Base plate building giants$ 2695 501A Unassembled Magnets 10 pak$ 1195 501 B Assembled Magnets 10 pakS 2200 502 Stands 110 uprights primarily fuselage easyS 950 504 Vertical press 5 pak holding spars leading trailing edges position$ 995 505 Steps 5 pakl adjustible leading & trailing edge positioning$ 595 506 Rib Holder 10 pak Use magnet building faster$ 995 ~TUFELDON J LIND COMPANY 3151 Caravelle Dr Lake Havasu City AZ 86403 C 16021453 7970 Send sell addressed stamped envelope catalog ot products M/C & Visa accepted December 1989 45 Fourmost Fuselage Fixture Mark II Fourmost Fuselage Fixture Mark II designed auto matically align fuselage structures built strings measuring eyeballing Price $5995 Simply slide four centering brackets track until align fire wall tail joint two bulkheads Clamp fuselage together lightly rubber bands structure will straight ready gluing Fixture will accomodate fuselages long four feet wide eight inches eight inches Please include $400 br Shipping Handling direct orders FOURMOST PRODUCTS 4040 24TH AVEFOREST GROVE OR 971165031 357-2732 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NiCd Batteries Ihe chargers YOU need packageFor Cycier-Chargec,,,, $23996 Fits 48V Rs 96V Tx packsPlus ened Ceii Others avaable write kier.. *3495Reguiar Modei $4696 ForPlus $3 S&H\ eiFor held kit smatPlus $3 S&H tipleelectric boat batteriesSpecify 612 24V Heavy Duty Model.. $5896 sport winch large boat andPlus $4 S&H electric power charging batteriesSpecify 6 1 2V CaRa Products ox 221 DealerinqurneslnveedCanton SO 57013 pp THERMAL CHARGER what looking electric sailplane good looks easy build fun fly great performance Thermal Charger Wing Span Wing Area Motor Included 60 Inches 545 Sq Inches Leisure 05 Electric C — t PRECISION PRODUCTS INC 714 592-5144 510 E Arrow Highway San Dimas CA 91773 way first day just little wind ran practice round let fliers prac tice own afterwards needed especially Alps because unfamiliar seaside slopes winds second day shot four good contest rounds fairly good west wind third day rather weak winds did round Some fliers went sight seeing some stayed practice fourth day expected good north winds finally arrived 12- 20-mph winds directly best slope made five rounds dinner delayed until 800 pm Rain forecast next day turned out expectedan off day kept people busy think happy time Evening entertainment included RoIf Girs berger designer RG series airfoils new Chairman FAI s F3B ClAM Subcom mitteeBB telling about airfoil develop ments showing Selig-Donovan Princeton wind tunnel video several times very popular conference about F3F rules future Viking Races took two hours de cide rules great meet again Derbyshire England October 1990 RoIf also showed two films about modeling full-scale gliding Switzerland 1942-44 100% professionally done included some unique things films original purpose PR Swiss Army Air Force long rainy day off Chas Gardner Brian Sharp England Scotland told about British Slope Cross-Country Racing ended 20-minute presentations six interesting thought planes entered contest pilots plus sometimes interpre ter Very popular too course pilots se lected very proud have opportunity tell about marvelous designs 'Then time get dressed banquetand long happy night special Viking Year award went Siegfried Schedel Bavaria Siegfried started out looking very much like beginner F3F practiced minute could find climbed steadily scoreboard ended fifth place beating 80% winning Danish team agreement best man won no protests during contest Includ ing practice must have close 1000 flights two three models minor damage landings com pletely repaired hour 'The next morning everybody packed went home again Anna Johannes owners Vigso Bugt Pension everyone stayed BB happy too said never better guests wished us come back soon hope will have success new American Sportsman F3B class dont know told fact F3B contests Denmark according local Sportsman rules far biggest problem num ber officials needed So decided cut down simply taking five steps 1 Eliminating Distance task altogether 2 Fly Duration task individual flights after another no group scoring 3 No working-time slots 4 Organizer-supplied winches 5 Only attempt flight tough pop off Its far simpler contest run because everybody can help another same way normal American Duration-only contest challenge airthe six-minute Preci sion Speed runis exactly same real F3B course guys would have liked fly Distance no way can make work Three weeks ago ran National Cham pionship F3B have separate Nats classes F3A F3B F3C etc 18 pi lots zero officials fixed se quence flying timekeeping flagging etc CD himself managed place second course way setting up will produce some breaks since people active time lunch break must put managed seven rounds two days including early dinner Sunday night Italian pizza res taurant everyone 15 50 years great fun Next weekend will busy practicing F3B team Paris Preben Danish teams managerBB have good team time mean have some bright young people team gonna win anything down Paris certainly will middle time team does have strongest men eitherthe members spread second tOth place Nats will survive physi cally mentally hope will learn some thing can used Czechoslovakia next year 1990 European F3B Championships Netherlands -1991 F3B World Championships Only has made Speed task better 18 seconds official contest dont count practice runs arrive Paris day before practice round would have liked few days 46 Model Aviation durable skis made lightweight aluminum feature steel spring holds ski rigid flight also elevates axle above ski no modifications cur rent gear wire needed can go wheels skis seconds side ski also has special edge allows excellent tracking icy surfaces avalisbie three sizes snd can purchased trikes just mains order please send check money order $200 shipping handling Add 8% sales tax Minnesota Allow 2 weeks delivery large scales please submit weight wing span Telephone inquires call Ron 612-781-7333 NORTHERN 20 30 Trike $2000 Mains $1500 MODELING 40 60 Trike $2200 Mains $1700 PRODUCTS Large Scale Trike $7500 Mains $5500 PO Box 21181 ColumbIa Heights MN 55421 781-7333 DIAMOND ShARPENS BLADES NA JIFFY GET GREAT EDGE ON THAT NO11 OR UBER SKIVER BLADE COMES WITH REVERSIBLE BLOCK 325 grit 1000 grit $1500 Replacement Block$850 ADD $175 P&H 6% sales tax CA AVAILABLE CERAMIC AND ARKANSAS WHETSTONES P 0. BOX 8 MOORPARK CA 93020 805 529-9313 short money time again Prebens letters always fun read full good information great time Preben 1987 following Osnabruck F3B World Champs staying same pension flying same slopes talked ahout wind north-facing bluff high above beach cant imagine finer place Slope flying once wrote bluff must 400 ft high Preben later called attention fact highest spot Denmark 350 ft still say looked high time remarks about fly F3B con tests could food thought US CDs run ning Sportsman multitask events Because no hard-and-fast rules can run SMT contests way makes sense local conditions Wingspan winch launches windspeed Wisconsins Lee Murray kind enough write share some interesting data proj ect has working Back 1986 several Sailplane fliers club began collect records flights IIIBTBI2IIN 11$ ELIcIT tITlES PndlgJ II HIngE. 33-3344-1346-774 Ill MItag learn about performance various mod els effects flying conditions etc records now include over 250 flights provide some insight flight performance related windspeed launch methods Sailplane type Virtually flights club field sod farm often damp compared higher ground evaporative cooling often limits thermal generation Location would important consideration comparing results tween clubs Winch launches using Two-Meter Prodi gy resulted flights 25 seconds longer av erage high-start widely recognized difference performance between wingspans also evident shown chart below AWRACE FLIGHT TIME VT HIIECSPHN 336 FlIght Histopa ii isA N1a Aa 3p 4 TIHH IN iI121IN146SB WII4GNFBS PPndlgyB 50-4 B CopiloA comparison theoretical flight times suggests effect involves differ ences sink rate difference between 2M Standard class 78 vs 100 larger difference between Standard Unlim ited Class 2M class RO-8 has old standby years E-205 wing pro file substituted performer Prodigy shows up also Flying moderate wind does decrease flight times based Prodigy flying off highstart chart titled Flight Times vs Windspeed shows relationshipwhich fact undoubtedly linear lack data shown linear Flight lAment WinO Spa. Pndlns-IhIhnlapt Sa N6 Ia N 3 lend Spend reason flight times appear correlated windspeed probably related getting height launches since winch flights did show same correlation Model & Average Flight Times Minutes 2-Meter Prodigy RO-8 Std Class Cumic XC/Unlimited Dynasoar Scale ASW-17 526 465 891 1022 428 As know am big advocate theoreti cal Sailplane performance analysis Lee John Hohensee developed market computer Sail plane design/analysis programs called PC-Soar MaxSoar BB Part quest tie theory reality analysis actual flight per formance Al Scidmore Professor Electrical Engineering University Wisconsin pursuing instrumentation Sailplane digital data logger hope someday ALL STAINLESS STEEL HEAD LITE IItm BEST GLOW PLUG CONNECTOR Stainless Steel HEAD LOCK BEST DESIGN Welded No Solder Acid Flux Flexing Wires BEST NiCad Field Replaceable 12 AH SANYO 15 AH PANASONIC BEST QUALITY & GUARANTEE MODEL PRODUCTS CORPORATION BEST PRICESt #045-WIO NiCad Charger$ 995 available write directSt #040-With NiCad$ 1595 add $100 $200 outside US St #041-With NiCad & Charger $ 2595 MODEL PRODUCTS CORP PO Box 100 Allamuchy NJ 07820 201850-1508 December 1989 47 will able share some hard numbers Sailplane performance have calibration data first versions altimeter temperature sensor sup ply voltage monitor velocity sensor Al has some improvements under way altitude velocity Tbe equipment will small enough fit inside X-Country Scale ships can mounted pod above wing smaller models would nice transmit digitally encoded data ground someone would like get involved would love bear him Presently sensor outputs 0-20 VDC Drop line Lee Murray 1300 Bay Ridge Road Appleton WI 54915 phone 1-414/7314848 Lees letter reminder its good idea keep logbook Gliders Person ally usually dont note time flight enter date place number flights windspeed flying conditions weight ballast used results changes trim reason recording flight times during prac tice session maximum time launch objective Practice occasion perfecting pre cision landing one-minute countdown trying out different thermaling techniques general doing wild crazy things dont dare try during contest Id like review about practice sessions future column Please write youd like share favorite meth ods How-to-make-molds video previously re viewed two Julian Tamezs instructional videos titled Vacuum Bag Cut ting Foam Cores Now Ive chance see Julians 34-hr tape called Making Fiberglass Molds Let tell theres lot informa tion Julian partner Greg Norsworthy go through process making fiberglass fuse lage Cross-Country ship start making plug making fiberglass molds finally laying up two halves fu selage joining together whole pro cess takes good deal time involves lot skill tricks trade As Julian says tape gives ABCs making molds what equipment materials will need manufacture kind fiber glass part have idea youd like make own F/G fuselages guarantee studying tape will save much time aggravation kept returning thought watching Guys like Bob Sealy Jerry Slates really earn money make nice fuselages such reasonable prices three Julians tapes $3495 less 20% NSS LSF members plus $350 shipping address Channel Productions 19827 Bishops Gate Suite No1 Humble TX 77338 Phone 1-713/443-1253 days 5403944 evenings Sportsman Multi-Task update winner isMark Allens Falcon 880 course Im re ferring Jim Grays RIC Soaring Digest Chal lenge Design contest Sportsman Multi-Task SMT Sailplanes very interesting competition because good de signs entered including several brand-new ones says Soaring lacking new exciting things days addition winning Falcon 880 featured October column other designs en tered alphabetical order Bob Dodgsons Camano Terry Edmonds Callisto Don Chan ceys Conquest Don Edbergs Hustler Jeremy Teos Odyssey Bob Sealys Pulsar Paul Carlsons Quasoar Max Mills Westwind Sportsman Multi-Task new contest con cept Its takeoff F3B Duration/Distance Speed task flying restricted aircraft simplified flexible contest operation SMT suitable intermediate-level fliers say about LSF Level 3 designed middle ground between AMA Thermal Duration flying real International F3B Soaring competi tion limitation maximum weight SMT planes intended keep Gliders nonintim idating Sportsman-level fliers Thermal Duration will always bedrock Soaring USA youll find addi tion some Distance Speed tasks just adds fun makes quite different ball game Sailplane fliers say looking something new challenging think SMT will provide excitement seek ing restriction SMT planes must weigh 75 oz ballast pretty well excludes F3B planes permits just about kits market plus original de signs approximately two-meter 115-inspan size range Now suggested SMT contest rules place see October column have de sign RCSD jury feels good plane event next step clubs around coun try try SMT contests practice sessions see works club has run Distance Speed tasks before first problem will making 3 New ARFs ZMP SUKHOI Su-26M 1/5 ScaleIMPALA Masters Pattern span 68 area 890 sq motor 4 stroke 120 equivspan 66 area 800 sq motor 4 stroke 120 60 rear Preassembled lightweight epoxy fuselage sheeted plug-in wingsPresssembled balsa fuselage veneersd plug-in wings 8 stabs sheeted stab fin & rudder 5 dia epoxy cowl texan canopy &Epoxy cowl pipe cover removable canopy Illustrated illustrated assembly manualassembly manual see hobby dealer order direct MONARCH AMA Sport Pattern span 66 area 750 sq motor 4 stroke 90 60 Cu Preassembled balsa fuselage venesred wing shaped balsa parts texan canopy epoxy cowl illustrated assembly manual c ZIMPRO MARKETING tu sOt arK OAK StOOL 55 35535 P001St 515 482 6155 48 Model Aviation AIR WOLF EPOXY FIBERGLASS FUSELAGES TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $21000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 Z ial Introductory Offer Frequency Conversion $3500 Includes Crystals Certification Special Fast Turnaround Now Available CALL Send Large Self Addressed Envelope Brochures UPS U S Mail Federai Express Used Mastercard Visa Accepted pair sighting devices used define two dimensionless planes 150 meters apart known Base Base B two bases just big windows sky delineate distance Glid ers need fly leg Speed Distance circuit RMSA PPSS clubs Colorado fly quite bit Distance club contests weve found hoop-on-a-tripod sighting device both simple make easy use first described Dan Pruss June 1983 Soaring column thismagazine dont save old sues MA send business-size envelope 25C stamp Ill return reprint Dans column showing make sighting device quick description Pruss sighting device 36-in length %2 music wire stuck holes drilled opposite sides plastic like Lucite metal block about 15 20 side A-in hole drilled precisely 900 %2 holes Through hole inserted 10in length A-in-GD brass tube bottom block drilled No 7 drill tapped x 20 attachment camera tripod operation set up sighting device near winches Base walk 150 meters upwind F3B crosswind AMA rules set down other sighting device Base B just look through brass tube sight Base device adjust ing head tripod Doing same thing Base Aie sighting Base B deviceguarantees wire hoops both bases exactly parallel other Necking down end brass tubes soldering short pieces two-nextsmaller-size tubes makes sighting process precise look through big end 150-meter distance can laid out measured length cable fishing leader stored fast-wind spool Just play out walk Base B wind up walk back whole procedure can done faster setting out winch Speed task run flier time flagger required Base B flag ger puts up flag Glider about half way Base B drops Glider breaks plane defined wire hoop flag must stay up Glider fails break planeie cuts turnso pilots timer can tell him go back try again timer usually calls Base turns pilot pilot needs stand near timer Base sighting device practice its best pilot get lined up Base can judge turn himself instead waiting Turn call Distance task usually run four pi lots flying man-on-man although can done time small contests needs flagger differently colored flag Base B plane four planes per heat youll need flaggers red white blue green colored flags course need establish before launching color signed pilot Holding up red white blue green flag also holding up Glider helps Base B crew determine plane flag Also weve found inex pensive Radio Shack-type two-way radio set very helpful communicating back forthISO meters just bit too far shouting As mentioned above first time two flying SMT need called contest Its good schedule couple practice sessions everyone gets hang flying Speed Distance tasks well getting accustomed flagging jobs Give try Please let know works out Airfoils Low Speeds title 398-page book Michael Selig John Donovan Da vid Fraser reporting long-awaited results tests using Princeton Universitys lowspeed wind tunnel book being published Herk Stokely Soartech #8 sells $20 ppd may order now Herk 1504 Horseshoe Drive Virginia Beach VA 23451 Princeton tests probably exten sive best controlled investigation model Sailplane airfoils ever done As such Sailplaners have extremely anxious read about what Michael John Dave have discoveredand some new super airfoils will forthcoming So Soartech #8 should very interesting popular read David Fraser also designer popular Sailplane Design computer program lat est Version 30 has Princeton data cludes 87 airfoils including flapped tripped versions David says Its quite gold Version 30 sells $35 Version 2 users can updated 30 returning diskette $10 Write Sailplane Design 1335 Slaton Dr Maple Glen PA 19002 Torrey Pines Scale Fun Fly Its short notice over Thanksgiving weekend Friday through Sunday Torrey Pines Gulls club will put Scale-only Slope Fun Fly fa mous Torrey Pines site just north San Diego Charley Morrey Slope Soaring News wrote invite Scale fans come fly Charley said details hadnt nailed Continued page 156 December 1989 49 Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royal Tower Hobbies World Engines Spectrum Analyzers CalIbrated Test Instruments Large Inventory RIC Parts Crystals THE PIPER BRAVE scale model Pipers latest Ag plane t wing span 30-33 lbs 5 cc power lb payload ational flaps hopper door onal Spreader Kit formed aluminum landing gear rglass cowls um-formed canopy tucted extruded foam ply hardwood E $269~ OPTIONAL $ 4fl95 Smoker l actually dusting KITSPREADER SEND $100 FOR CATALOG OFQ 4/RT 1 NEODESHA KS 66757 SAC KITS AND ACCESSORIES316 325-2821 Free Shipping Kit OrdersScott Airplane CompanyVISA/MASTERCARD GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation
Edition: Model Aviation - 1989/12
Page Numbers: 44, 45, 46, 47, 48, 49, 156
NEAT constant-tension winch Jack Perecman Golden Valley MN sent excellent photos very neat winch Jacks letter tells about Enclosed will find some photos showing constant-tension winch designed built winch presently its second season far has proven quite reliable Im mem ber Minnesota RC Soaring Society have used winch both club fun-flys contests motor starter motor Johnson outboard has high torque plus ad vantages both long shaft thread end splines near motor face make mounting drum quite easy photo shows winch turnaround transportation mode Another photos shows right side winch its operating position wheels have flipped out underneath frame now resting ground foot treadle behind attached winch means bicycle brake cable operation farther treadle pushed down greater tension line T handle device top battery emer gency kill switch threaded rod crank low motor pivots motor/drum assembly fine adjustment line level winding final photo shows main parts constant-tension device Pushing down foot treadle pulls cable causes switch arm pivot counterclockwise away spring-loaded roller arms microswitch normally closed As soon switch pulled away roller arms closes en ergizes solenoid supplies power motor As tension line increases roller arms begin pivot toward switch ten sion line counterbalanced two springs desired tension achieved left roller arm touches microswitch open ing turning off solenoid will stay off until tension line decreases greater tension desired operator pushes foot treadle down pulls switch farther away roller arm springs have stretched before arm contacts switch operation due dampening effect stretch line way device automatically pulses motor off very similar what operator would using normal foot switch Other features include one-way clutch roller can engaged disengaged moving 44 Model Aviation Radio Control Soaring Byron Blakeslee 3134 N Winnebago Dr Sedalia CO 80135 Four Ts Teutonic Tailless Terror Team Germany flew Viking Cup Slope Races held Denmark Note models has some sort experimental aftmounted horizontal stability augmentation surface model just front has extended fu selage central fin other wings use tip-mounted fins Photo Preben Norhoim Swiss team Viking Cup meet Manager RoIf Gersberger right Norholm Jack Perecman designed winch its constant-tension mechanism Motor starter Johnson outboard motor Jack en gineer 3M company designs sort thing living Items note T-handled kill switch mounted right bat tery terminal extra-heavy battery post clamps flip-up wheel carriage Foot treadle gas pedal tells winch much tension put towline winch motor cycles automatically maintain desired tension Author Blakeslee has info column small black lever seen just above center shaft clutch roller uses Torrington oneway roller bearing addition just below roller mounted roller arm small tri angular piece urethane rubber rubs rim drum effectively brakes drum slightly prevent backlashes main purpose building winch first see simple reliable constant-tension device could built F3B competition days weak link Second perhaps applicable average club putting stop switch arm possible easily ad just maximum tension pilot can achieve using winch have able launch Gnome hand-launched Glider immediately readjust winch launching Windsong addition possible beginners have con fidence launching airplanes fear folding wings can see what beautiful job engineering fabricating Jack did winch especially constant-tension device CT mechanism would course work winch just Jacks outboard-motor design Some careful machinework would need done duplicate though Jack said hed make drawings avail able theres enough interest can con tact Jack Pereeman 224 Natchez Ave North Golden Valley MN 55422 Incidenially winches should have kill switch similar Jacks cut off battery power case emergency common situ ation stuck solenoid tries strain plane through turnaround need switch can operate quickly state severe panic RV shops sell big copper knife switches about $20 mount right battery post Theyre cheap insurance Danish connection risk infringing Mark Triebes turf Id like print letter friend Preben Norholm Copenhagen describing 1989 Viking Cup Race Vi king Cup biggest annual International F3F event held North Sea slopes near Hanstholm Denmark last June F3F FAI Provisional event Slope Racers fly 10 laps 100-meter course against clockone plane time Slope Racing US traditionally run exciting way te wtth four planes flying against other heat However Europeans decided certain prospect midair collisions consequent loss hundreds dollars worth planes equipment sufficient rea son race one-at-a-time Preben founders F3F Racing justifiably proud success Viking Cup has achieved Preben too beauty event like gathering gether enthusiasts different coun tries Preben would like US fliers participate too team South Bay club got serious thinking stage couldnt quite man age trip 89 Maybe next year Isnt wonderful have hobby/sport can travel almost country world welcomed instant friends identical interests Prebens letter ended up 40 contestants coun tries spread Iceland Israel almost everything between came Switzer land Bavaria Berlin Westphalia Osnabruck area England Scotland Norway Nic Wright England won again Denmark took team trophy followed England NorIv finest model building equipment manufactured kahe4 zfloS4loAuh1wi 4ohrk a41/i/nna 94eady& Mdc dealer order direct-500A Magic Magnet Builder Icontains 16x48 Steel Base Plate 30 Magnets 10 stands S 9450 SOOB Master Magic Magnet Builder Icontains 1 6x4B Steel base plate 60 Magnets 20 stands 10 Vert press 10 steps 20 rib holders 50 sets nuts & bolts$16895 503B Base Plate Extension 1 6x1 6 Steel Base plate building giants$ 2695 501A Unassembled Magnets 10 pak$ 1195 501 B Assembled Magnets 10 pakS 2200 502 Stands 110 uprights primarily fuselage easyS 950 504 Vertical press 5 pak holding spars leading trailing edges position$ 995 505 Steps 5 pakl adjustible leading & trailing edge positioning$ 595 506 Rib Holder 10 pak Use magnet building faster$ 995 ~TUFELDON J LIND COMPANY 3151 Caravelle Dr Lake Havasu City AZ 86403 C 16021453 7970 Send sell addressed stamped envelope catalog ot products M/C & Visa accepted December 1989 45 Fourmost Fuselage Fixture Mark II Fourmost Fuselage Fixture Mark II designed auto matically align fuselage structures built strings measuring eyeballing Price $5995 Simply slide four centering brackets track until align fire wall tail joint two bulkheads Clamp fuselage together lightly rubber bands structure will straight ready gluing Fixture will accomodate fuselages long four feet wide eight inches eight inches Please include $400 br Shipping Handling direct orders FOURMOST PRODUCTS 4040 24TH AVEFOREST GROVE OR 971165031 357-2732 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NiCd Batteries Ihe chargers YOU need packageFor Cycier-Chargec,,,, $23996 Fits 48V Rs 96V Tx packsPlus ened Ceii Others avaable write kier.. *3495Reguiar Modei $4696 ForPlus $3 S&H\ eiFor held kit smatPlus $3 S&H tipleelectric boat batteriesSpecify 612 24V Heavy Duty Model.. $5896 sport winch large boat andPlus $4 S&H electric power charging batteriesSpecify 6 1 2V CaRa Products ox 221 DealerinqurneslnveedCanton SO 57013 pp THERMAL CHARGER what looking electric sailplane good looks easy build fun fly great performance Thermal Charger Wing Span Wing Area Motor Included 60 Inches 545 Sq Inches Leisure 05 Electric C — t PRECISION PRODUCTS INC 714 592-5144 510 E Arrow Highway San Dimas CA 91773 way first day just little wind ran practice round let fliers prac tice own afterwards needed especially Alps because unfamiliar seaside slopes winds second day shot four good contest rounds fairly good west wind third day rather weak winds did round Some fliers went sight seeing some stayed practice fourth day expected good north winds finally arrived 12- 20-mph winds directly best slope made five rounds dinner delayed until 800 pm Rain forecast next day turned out expectedan off day kept people busy think happy time Evening entertainment included RoIf Girs berger designer RG series airfoils new Chairman FAI s F3B ClAM Subcom mitteeBB telling about airfoil develop ments showing Selig-Donovan Princeton wind tunnel video several times very popular conference about F3F rules future Viking Races took two hours de cide rules great meet again Derbyshire England October 1990 RoIf also showed two films about modeling full-scale gliding Switzerland 1942-44 100% professionally done included some unique things films original purpose PR Swiss Army Air Force long rainy day off Chas Gardner Brian Sharp England Scotland told about British Slope Cross-Country Racing ended 20-minute presentations six interesting thought planes entered contest pilots plus sometimes interpre ter Very popular too course pilots se lected very proud have opportunity tell about marvelous designs 'Then time get dressed banquetand long happy night special Viking Year award went Siegfried Schedel Bavaria Siegfried started out looking very much like beginner F3F practiced minute could find climbed steadily scoreboard ended fifth place beating 80% winning Danish team agreement best man won no protests during contest Includ ing practice must have close 1000 flights two three models minor damage landings com pletely repaired hour 'The next morning everybody packed went home again Anna Johannes owners Vigso Bugt Pension everyone stayed BB happy too said never better guests wished us come back soon hope will have success new American Sportsman F3B class dont know told fact F3B contests Denmark according local Sportsman rules far biggest problem num ber officials needed So decided cut down simply taking five steps 1 Eliminating Distance task altogether 2 Fly Duration task individual flights after another no group scoring 3 No working-time slots 4 Organizer-supplied winches 5 Only attempt flight tough pop off Its far simpler contest run because everybody can help another same way normal American Duration-only contest challenge airthe six-minute Preci sion Speed runis exactly same real F3B course guys would have liked fly Distance no way can make work Three weeks ago ran National Cham pionship F3B have separate Nats classes F3A F3B F3C etc 18 pi lots zero officials fixed se quence flying timekeeping flagging etc CD himself managed place second course way setting up will produce some breaks since people active time lunch break must put managed seven rounds two days including early dinner Sunday night Italian pizza res taurant everyone 15 50 years great fun Next weekend will busy practicing F3B team Paris Preben Danish teams managerBB have good team time mean have some bright young people team gonna win anything down Paris certainly will middle time team does have strongest men eitherthe members spread second tOth place Nats will survive physi cally mentally hope will learn some thing can used Czechoslovakia next year 1990 European F3B Championships Netherlands -1991 F3B World Championships Only has made Speed task better 18 seconds official contest dont count practice runs arrive Paris day before practice round would have liked few days 46 Model Aviation durable skis made lightweight aluminum feature steel spring holds ski rigid flight also elevates axle above ski no modifications cur rent gear wire needed can go wheels skis seconds side ski also has special edge allows excellent tracking icy surfaces avalisbie three sizes snd can purchased trikes just mains order please send check money order $200 shipping handling Add 8% sales tax Minnesota Allow 2 weeks delivery large scales please submit weight wing span Telephone inquires call Ron 612-781-7333 NORTHERN 20 30 Trike $2000 Mains $1500 MODELING 40 60 Trike $2200 Mains $1700 PRODUCTS Large Scale Trike $7500 Mains $5500 PO Box 21181 ColumbIa Heights MN 55421 781-7333 DIAMOND ShARPENS BLADES NA JIFFY GET GREAT EDGE ON THAT NO11 OR UBER SKIVER BLADE COMES WITH REVERSIBLE BLOCK 325 grit 1000 grit $1500 Replacement Block$850 ADD $175 P&H 6% sales tax CA AVAILABLE CERAMIC AND ARKANSAS WHETSTONES P 0. BOX 8 MOORPARK CA 93020 805 529-9313 short money time again Prebens letters always fun read full good information great time Preben 1987 following Osnabruck F3B World Champs staying same pension flying same slopes talked ahout wind north-facing bluff high above beach cant imagine finer place Slope flying once wrote bluff must 400 ft high Preben later called attention fact highest spot Denmark 350 ft still say looked high time remarks about fly F3B con tests could food thought US CDs run ning Sportsman multitask events Because no hard-and-fast rules can run SMT contests way makes sense local conditions Wingspan winch launches windspeed Wisconsins Lee Murray kind enough write share some interesting data proj ect has working Back 1986 several Sailplane fliers club began collect records flights IIIBTBI2IIN 11$ ELIcIT tITlES PndlgJ II HIngE. 33-3344-1346-774 Ill MItag learn about performance various mod els effects flying conditions etc records now include over 250 flights provide some insight flight performance related windspeed launch methods Sailplane type Virtually flights club field sod farm often damp compared higher ground evaporative cooling often limits thermal generation Location would important consideration comparing results tween clubs Winch launches using Two-Meter Prodi gy resulted flights 25 seconds longer av erage high-start widely recognized difference performance between wingspans also evident shown chart below AWRACE FLIGHT TIME VT HIIECSPHN 336 FlIght Histopa ii isA N1a Aa 3p 4 TIHH IN iI121IN146SB WII4GNFBS PPndlgyB 50-4 B CopiloA comparison theoretical flight times suggests effect involves differ ences sink rate difference between 2M Standard class 78 vs 100 larger difference between Standard Unlim ited Class 2M class RO-8 has old standby years E-205 wing pro file substituted performer Prodigy shows up also Flying moderate wind does decrease flight times based Prodigy flying off highstart chart titled Flight Times vs Windspeed shows relationshipwhich fact undoubtedly linear lack data shown linear Flight lAment WinO Spa. Pndlns-IhIhnlapt Sa N6 Ia N 3 lend Spend reason flight times appear correlated windspeed probably related getting height launches since winch flights did show same correlation Model & Average Flight Times Minutes 2-Meter Prodigy RO-8 Std Class Cumic XC/Unlimited Dynasoar Scale ASW-17 526 465 891 1022 428 As know am big advocate theoreti cal Sailplane performance analysis Lee John Hohensee developed market computer Sail plane design/analysis programs called PC-Soar MaxSoar BB Part quest tie theory reality analysis actual flight per formance Al Scidmore Professor Electrical Engineering University Wisconsin pursuing instrumentation Sailplane digital data logger hope someday ALL STAINLESS STEEL HEAD LITE IItm BEST GLOW PLUG CONNECTOR Stainless Steel HEAD LOCK BEST DESIGN Welded No Solder Acid Flux Flexing Wires BEST NiCad Field Replaceable 12 AH SANYO 15 AH PANASONIC BEST QUALITY & GUARANTEE MODEL PRODUCTS CORPORATION BEST PRICESt #045-WIO NiCad Charger$ 995 available write directSt #040-With NiCad$ 1595 add $100 $200 outside US St #041-With NiCad & Charger $ 2595 MODEL PRODUCTS CORP PO Box 100 Allamuchy NJ 07820 201850-1508 December 1989 47 will able share some hard numbers Sailplane performance have calibration data first versions altimeter temperature sensor sup ply voltage monitor velocity sensor Al has some improvements under way altitude velocity Tbe equipment will small enough fit inside X-Country Scale ships can mounted pod above wing smaller models would nice transmit digitally encoded data ground someone would like get involved would love bear him Presently sensor outputs 0-20 VDC Drop line Lee Murray 1300 Bay Ridge Road Appleton WI 54915 phone 1-414/7314848 Lees letter reminder its good idea keep logbook Gliders Person ally usually dont note time flight enter date place number flights windspeed flying conditions weight ballast used results changes trim reason recording flight times during prac tice session maximum time launch objective Practice occasion perfecting pre cision landing one-minute countdown trying out different thermaling techniques general doing wild crazy things dont dare try during contest Id like review about practice sessions future column Please write youd like share favorite meth ods How-to-make-molds video previously re viewed two Julian Tamezs instructional videos titled Vacuum Bag Cut ting Foam Cores Now Ive chance see Julians 34-hr tape called Making Fiberglass Molds Let tell theres lot informa tion Julian partner Greg Norsworthy go through process making fiberglass fuse lage Cross-Country ship start making plug making fiberglass molds finally laying up two halves fu selage joining together whole pro cess takes good deal time involves lot skill tricks trade As Julian says tape gives ABCs making molds what equipment materials will need manufacture kind fiber glass part have idea youd like make own F/G fuselages guarantee studying tape will save much time aggravation kept returning thought watching Guys like Bob Sealy Jerry Slates really earn money make nice fuselages such reasonable prices three Julians tapes $3495 less 20% NSS LSF members plus $350 shipping address Channel Productions 19827 Bishops Gate Suite No1 Humble TX 77338 Phone 1-713/443-1253 days 5403944 evenings Sportsman Multi-Task update winner isMark Allens Falcon 880 course Im re ferring Jim Grays RIC Soaring Digest Chal lenge Design contest Sportsman Multi-Task SMT Sailplanes very interesting competition because good de signs entered including several brand-new ones says Soaring lacking new exciting things days addition winning Falcon 880 featured October column other designs en tered alphabetical order Bob Dodgsons Camano Terry Edmonds Callisto Don Chan ceys Conquest Don Edbergs Hustler Jeremy Teos Odyssey Bob Sealys Pulsar Paul Carlsons Quasoar Max Mills Westwind Sportsman Multi-Task new contest con cept Its takeoff F3B Duration/Distance Speed task flying restricted aircraft simplified flexible contest operation SMT suitable intermediate-level fliers say about LSF Level 3 designed middle ground between AMA Thermal Duration flying real International F3B Soaring competi tion limitation maximum weight SMT planes intended keep Gliders nonintim idating Sportsman-level fliers Thermal Duration will always bedrock Soaring USA youll find addi tion some Distance Speed tasks just adds fun makes quite different ball game Sailplane fliers say looking something new challenging think SMT will provide excitement seek ing restriction SMT planes must weigh 75 oz ballast pretty well excludes F3B planes permits just about kits market plus original de signs approximately two-meter 115-inspan size range Now suggested SMT contest rules place see October column have de sign RCSD jury feels good plane event next step clubs around coun try try SMT contests practice sessions see works club has run Distance Speed tasks before first problem will making 3 New ARFs ZMP SUKHOI Su-26M 1/5 ScaleIMPALA Masters Pattern span 68 area 890 sq motor 4 stroke 120 equivspan 66 area 800 sq motor 4 stroke 120 60 rear Preassembled lightweight epoxy fuselage sheeted plug-in wingsPresssembled balsa fuselage veneersd plug-in wings 8 stabs sheeted stab fin & rudder 5 dia epoxy cowl texan canopy &Epoxy cowl pipe cover removable canopy Illustrated illustrated assembly manualassembly manual see hobby dealer order direct MONARCH AMA Sport Pattern span 66 area 750 sq motor 4 stroke 90 60 Cu Preassembled balsa fuselage venesred wing shaped balsa parts texan canopy epoxy cowl illustrated assembly manual c ZIMPRO MARKETING tu sOt arK OAK StOOL 55 35535 P001St 515 482 6155 48 Model Aviation AIR WOLF EPOXY FIBERGLASS FUSELAGES TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $21000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 Z ial Introductory Offer Frequency Conversion $3500 Includes Crystals Certification Special Fast Turnaround Now Available CALL Send Large Self Addressed Envelope Brochures UPS U S Mail Federai Express Used Mastercard Visa Accepted pair sighting devices used define two dimensionless planes 150 meters apart known Base Base B two bases just big windows sky delineate distance Glid ers need fly leg Speed Distance circuit RMSA PPSS clubs Colorado fly quite bit Distance club contests weve found hoop-on-a-tripod sighting device both simple make easy use first described Dan Pruss June 1983 Soaring column thismagazine dont save old sues MA send business-size envelope 25C stamp Ill return reprint Dans column showing make sighting device quick description Pruss sighting device 36-in length %2 music wire stuck holes drilled opposite sides plastic like Lucite metal block about 15 20 side A-in hole drilled precisely 900 %2 holes Through hole inserted 10in length A-in-GD brass tube bottom block drilled No 7 drill tapped x 20 attachment camera tripod operation set up sighting device near winches Base walk 150 meters upwind F3B crosswind AMA rules set down other sighting device Base B just look through brass tube sight Base device adjust ing head tripod Doing same thing Base Aie sighting Base B deviceguarantees wire hoops both bases exactly parallel other Necking down end brass tubes soldering short pieces two-nextsmaller-size tubes makes sighting process precise look through big end 150-meter distance can laid out measured length cable fishing leader stored fast-wind spool Just play out walk Base B wind up walk back whole procedure can done faster setting out winch Speed task run flier time flagger required Base B flag ger puts up flag Glider about half way Base B drops Glider breaks plane defined wire hoop flag must stay up Glider fails break planeie cuts turnso pilots timer can tell him go back try again timer usually calls Base turns pilot pilot needs stand near timer Base sighting device practice its best pilot get lined up Base can judge turn himself instead waiting Turn call Distance task usually run four pi lots flying man-on-man although can done time small contests needs flagger differently colored flag Base B plane four planes per heat youll need flaggers red white blue green colored flags course need establish before launching color signed pilot Holding up red white blue green flag also holding up Glider helps Base B crew determine plane flag Also weve found inex pensive Radio Shack-type two-way radio set very helpful communicating back forthISO meters just bit too far shouting As mentioned above first time two flying SMT need called contest Its good schedule couple practice sessions everyone gets hang flying Speed Distance tasks well getting accustomed flagging jobs Give try Please let know works out Airfoils Low Speeds title 398-page book Michael Selig John Donovan Da vid Fraser reporting long-awaited results tests using Princeton Universitys lowspeed wind tunnel book being published Herk Stokely Soartech #8 sells $20 ppd may order now Herk 1504 Horseshoe Drive Virginia Beach VA 23451 Princeton tests probably exten sive best controlled investigation model Sailplane airfoils ever done As such Sailplaners have extremely anxious read about what Michael John Dave have discoveredand some new super airfoils will forthcoming So Soartech #8 should very interesting popular read David Fraser also designer popular Sailplane Design computer program lat est Version 30 has Princeton data cludes 87 airfoils including flapped tripped versions David says Its quite gold Version 30 sells $35 Version 2 users can updated 30 returning diskette $10 Write Sailplane Design 1335 Slaton Dr Maple Glen PA 19002 Torrey Pines Scale Fun Fly Its short notice over Thanksgiving weekend Friday through Sunday Torrey Pines Gulls club will put Scale-only Slope Fun Fly fa mous Torrey Pines site just north San Diego Charley Morrey Slope Soaring News wrote invite Scale fans come fly Charley said details hadnt nailed Continued page 156 December 1989 49 Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royal Tower Hobbies World Engines Spectrum Analyzers CalIbrated Test Instruments Large Inventory RIC Parts Crystals THE PIPER BRAVE scale model Pipers latest Ag plane t wing span 30-33 lbs 5 cc power lb payload ational flaps hopper door onal Spreader Kit formed aluminum landing gear rglass cowls um-formed canopy tucted extruded foam ply hardwood E $269~ OPTIONAL $ 4fl95 Smoker l actually dusting KITSPREADER SEND $100 FOR CATALOG OFQ 4/RT 1 NEODESHA KS 66757 SAC KITS AND ACCESSORIES316 325-2821 Free Shipping Kit OrdersScott Airplane CompanyVISA/MASTERCARD GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation
Edition: Model Aviation - 1989/12
Page Numbers: 44, 45, 46, 47, 48, 49, 156
NEAT constant-tension winch Jack Perecman Golden Valley MN sent excellent photos very neat winch Jacks letter tells about Enclosed will find some photos showing constant-tension winch designed built winch presently its second season far has proven quite reliable Im mem ber Minnesota RC Soaring Society have used winch both club fun-flys contests motor starter motor Johnson outboard has high torque plus ad vantages both long shaft thread end splines near motor face make mounting drum quite easy photo shows winch turnaround transportation mode Another photos shows right side winch its operating position wheels have flipped out underneath frame now resting ground foot treadle behind attached winch means bicycle brake cable operation farther treadle pushed down greater tension line T handle device top battery emer gency kill switch threaded rod crank low motor pivots motor/drum assembly fine adjustment line level winding final photo shows main parts constant-tension device Pushing down foot treadle pulls cable causes switch arm pivot counterclockwise away spring-loaded roller arms microswitch normally closed As soon switch pulled away roller arms closes en ergizes solenoid supplies power motor As tension line increases roller arms begin pivot toward switch ten sion line counterbalanced two springs desired tension achieved left roller arm touches microswitch open ing turning off solenoid will stay off until tension line decreases greater tension desired operator pushes foot treadle down pulls switch farther away roller arm springs have stretched before arm contacts switch operation due dampening effect stretch line way device automatically pulses motor off very similar what operator would using normal foot switch Other features include one-way clutch roller can engaged disengaged moving 44 Model Aviation Radio Control Soaring Byron Blakeslee 3134 N Winnebago Dr Sedalia CO 80135 Four Ts Teutonic Tailless Terror Team Germany flew Viking Cup Slope Races held Denmark Note models has some sort experimental aftmounted horizontal stability augmentation surface model just front has extended fu selage central fin other wings use tip-mounted fins Photo Preben Norhoim Swiss team Viking Cup meet Manager RoIf Gersberger right Norholm Jack Perecman designed winch its constant-tension mechanism Motor starter Johnson outboard motor Jack en gineer 3M company designs sort thing living Items note T-handled kill switch mounted right bat tery terminal extra-heavy battery post clamps flip-up wheel carriage Foot treadle gas pedal tells winch much tension put towline winch motor cycles automatically maintain desired tension Author Blakeslee has info column small black lever seen just above center shaft clutch roller uses Torrington oneway roller bearing addition just below roller mounted roller arm small tri angular piece urethane rubber rubs rim drum effectively brakes drum slightly prevent backlashes main purpose building winch first see simple reliable constant-tension device could built F3B competition days weak link Second perhaps applicable average club putting stop switch arm possible easily ad just maximum tension pilot can achieve using winch have able launch Gnome hand-launched Glider immediately readjust winch launching Windsong addition possible beginners have con fidence launching airplanes fear folding wings can see what beautiful job engineering fabricating Jack did winch especially constant-tension device CT mechanism would course work winch just Jacks outboard-motor design Some careful machinework would need done duplicate though Jack said hed make drawings avail able theres enough interest can con tact Jack Pereeman 224 Natchez Ave North Golden Valley MN 55422 Incidenially winches should have kill switch similar Jacks cut off battery power case emergency common situ ation stuck solenoid tries strain plane through turnaround need switch can operate quickly state severe panic RV shops sell big copper knife switches about $20 mount right battery post Theyre cheap insurance Danish connection risk infringing Mark Triebes turf Id like print letter friend Preben Norholm Copenhagen describing 1989 Viking Cup Race Vi king Cup biggest annual International F3F event held North Sea slopes near Hanstholm Denmark last June F3F FAI Provisional event Slope Racers fly 10 laps 100-meter course against clockone plane time Slope Racing US traditionally run exciting way te wtth four planes flying against other heat However Europeans decided certain prospect midair collisions consequent loss hundreds dollars worth planes equipment sufficient rea son race one-at-a-time Preben founders F3F Racing justifiably proud success Viking Cup has achieved Preben too beauty event like gathering gether enthusiasts different coun tries Preben would like US fliers participate too team South Bay club got serious thinking stage couldnt quite man age trip 89 Maybe next year Isnt wonderful have hobby/sport can travel almost country world welcomed instant friends identical interests Prebens letter ended up 40 contestants coun tries spread Iceland Israel almost everything between came Switzer land Bavaria Berlin Westphalia Osnabruck area England Scotland Norway Nic Wright England won again Denmark took team trophy followed England NorIv finest model building equipment manufactured kahe4 zfloS4loAuh1wi 4ohrk a41/i/nna 94eady& Mdc dealer order direct-500A Magic Magnet Builder Icontains 16x48 Steel Base Plate 30 Magnets 10 stands S 9450 SOOB Master Magic Magnet Builder Icontains 1 6x4B Steel base plate 60 Magnets 20 stands 10 Vert press 10 steps 20 rib holders 50 sets nuts & bolts$16895 503B Base Plate Extension 1 6x1 6 Steel Base plate building giants$ 2695 501A Unassembled Magnets 10 pak$ 1195 501 B Assembled Magnets 10 pakS 2200 502 Stands 110 uprights primarily fuselage easyS 950 504 Vertical press 5 pak holding spars leading trailing edges position$ 995 505 Steps 5 pakl adjustible leading & trailing edge positioning$ 595 506 Rib Holder 10 pak Use magnet building faster$ 995 ~TUFELDON J LIND COMPANY 3151 Caravelle Dr Lake Havasu City AZ 86403 C 16021453 7970 Send sell addressed stamped envelope catalog ot products M/C & Visa accepted December 1989 45 Fourmost Fuselage Fixture Mark II Fourmost Fuselage Fixture Mark II designed auto matically align fuselage structures built strings measuring eyeballing Price $5995 Simply slide four centering brackets track until align fire wall tail joint two bulkheads Clamp fuselage together lightly rubber bands structure will straight ready gluing Fixture will accomodate fuselages long four feet wide eight inches eight inches Please include $400 br Shipping Handling direct orders FOURMOST PRODUCTS 4040 24TH AVEFOREST GROVE OR 971165031 357-2732 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NiCd Batteries Ihe chargers YOU need packageFor Cycier-Chargec,,,, $23996 Fits 48V Rs 96V Tx packsPlus ened Ceii Others avaable write kier.. *3495Reguiar Modei $4696 ForPlus $3 S&H\ eiFor held kit smatPlus $3 S&H tipleelectric boat batteriesSpecify 612 24V Heavy Duty Model.. $5896 sport winch large boat andPlus $4 S&H electric power charging batteriesSpecify 6 1 2V CaRa Products ox 221 DealerinqurneslnveedCanton SO 57013 pp THERMAL CHARGER what looking electric sailplane good looks easy build fun fly great performance Thermal Charger Wing Span Wing Area Motor Included 60 Inches 545 Sq Inches Leisure 05 Electric C — t PRECISION PRODUCTS INC 714 592-5144 510 E Arrow Highway San Dimas CA 91773 way first day just little wind ran practice round let fliers prac tice own afterwards needed especially Alps because unfamiliar seaside slopes winds second day shot four good contest rounds fairly good west wind third day rather weak winds did round Some fliers went sight seeing some stayed practice fourth day expected good north winds finally arrived 12- 20-mph winds directly best slope made five rounds dinner delayed until 800 pm Rain forecast next day turned out expectedan off day kept people busy think happy time Evening entertainment included RoIf Girs berger designer RG series airfoils new Chairman FAI s F3B ClAM Subcom mitteeBB telling about airfoil develop ments showing Selig-Donovan Princeton wind tunnel video several times very popular conference about F3F rules future Viking Races took two hours de cide rules great meet again Derbyshire England October 1990 RoIf also showed two films about modeling full-scale gliding Switzerland 1942-44 100% professionally done included some unique things films original purpose PR Swiss Army Air Force long rainy day off Chas Gardner Brian Sharp England Scotland told about British Slope Cross-Country Racing ended 20-minute presentations six interesting thought planes entered contest pilots plus sometimes interpre ter Very popular too course pilots se lected very proud have opportunity tell about marvelous designs 'Then time get dressed banquetand long happy night special Viking Year award went Siegfried Schedel Bavaria Siegfried started out looking very much like beginner F3F practiced minute could find climbed steadily scoreboard ended fifth place beating 80% winning Danish team agreement best man won no protests during contest Includ ing practice must have close 1000 flights two three models minor damage landings com pletely repaired hour 'The next morning everybody packed went home again Anna Johannes owners Vigso Bugt Pension everyone stayed BB happy too said never better guests wished us come back soon hope will have success new American Sportsman F3B class dont know told fact F3B contests Denmark according local Sportsman rules far biggest problem num ber officials needed So decided cut down simply taking five steps 1 Eliminating Distance task altogether 2 Fly Duration task individual flights after another no group scoring 3 No working-time slots 4 Organizer-supplied winches 5 Only attempt flight tough pop off Its far simpler contest run because everybody can help another same way normal American Duration-only contest challenge airthe six-minute Preci sion Speed runis exactly same real F3B course guys would have liked fly Distance no way can make work Three weeks ago ran National Cham pionship F3B have separate Nats classes F3A F3B F3C etc 18 pi lots zero officials fixed se quence flying timekeeping flagging etc CD himself managed place second course way setting up will produce some breaks since people active time lunch break must put managed seven rounds two days including early dinner Sunday night Italian pizza res taurant everyone 15 50 years great fun Next weekend will busy practicing F3B team Paris Preben Danish teams managerBB have good team time mean have some bright young people team gonna win anything down Paris certainly will middle time team does have strongest men eitherthe members spread second tOth place Nats will survive physi cally mentally hope will learn some thing can used Czechoslovakia next year 1990 European F3B Championships Netherlands -1991 F3B World Championships Only has made Speed task better 18 seconds official contest dont count practice runs arrive Paris day before practice round would have liked few days 46 Model Aviation durable skis made lightweight aluminum feature steel spring holds ski rigid flight also elevates axle above ski no modifications cur rent gear wire needed can go wheels skis seconds side ski also has special edge allows excellent tracking icy surfaces avalisbie three sizes snd can purchased trikes just mains order please send check money order $200 shipping handling Add 8% sales tax Minnesota Allow 2 weeks delivery large scales please submit weight wing span Telephone inquires call Ron 612-781-7333 NORTHERN 20 30 Trike $2000 Mains $1500 MODELING 40 60 Trike $2200 Mains $1700 PRODUCTS Large Scale Trike $7500 Mains $5500 PO Box 21181 ColumbIa Heights MN 55421 781-7333 DIAMOND ShARPENS BLADES NA JIFFY GET GREAT EDGE ON THAT NO11 OR UBER SKIVER BLADE COMES WITH REVERSIBLE BLOCK 325 grit 1000 grit $1500 Replacement Block$850 ADD $175 P&H 6% sales tax CA AVAILABLE CERAMIC AND ARKANSAS WHETSTONES P 0. BOX 8 MOORPARK CA 93020 805 529-9313 short money time again Prebens letters always fun read full good information great time Preben 1987 following Osnabruck F3B World Champs staying same pension flying same slopes talked ahout wind north-facing bluff high above beach cant imagine finer place Slope flying once wrote bluff must 400 ft high Preben later called attention fact highest spot Denmark 350 ft still say looked high time remarks about fly F3B con tests could food thought US CDs run ning Sportsman multitask events Because no hard-and-fast rules can run SMT contests way makes sense local conditions Wingspan winch launches windspeed Wisconsins Lee Murray kind enough write share some interesting data proj ect has working Back 1986 several Sailplane fliers club began collect records flights IIIBTBI2IIN 11$ ELIcIT tITlES PndlgJ II HIngE. 33-3344-1346-774 Ill MItag learn about performance various mod els effects flying conditions etc records now include over 250 flights provide some insight flight performance related windspeed launch methods Sailplane type Virtually flights club field sod farm often damp compared higher ground evaporative cooling often limits thermal generation Location would important consideration comparing results tween clubs Winch launches using Two-Meter Prodi gy resulted flights 25 seconds longer av erage high-start widely recognized difference performance between wingspans also evident shown chart below AWRACE FLIGHT TIME VT HIIECSPHN 336 FlIght Histopa ii isA N1a Aa 3p 4 TIHH IN iI121IN146SB WII4GNFBS PPndlgyB 50-4 B CopiloA comparison theoretical flight times suggests effect involves differ ences sink rate difference between 2M Standard class 78 vs 100 larger difference between Standard Unlim ited Class 2M class RO-8 has old standby years E-205 wing pro file substituted performer Prodigy shows up also Flying moderate wind does decrease flight times based Prodigy flying off highstart chart titled Flight Times vs Windspeed shows relationshipwhich fact undoubtedly linear lack data shown linear Flight lAment WinO Spa. Pndlns-IhIhnlapt Sa N6 Ia N 3 lend Spend reason flight times appear correlated windspeed probably related getting height launches since winch flights did show same correlation Model & Average Flight Times Minutes 2-Meter Prodigy RO-8 Std Class Cumic XC/Unlimited Dynasoar Scale ASW-17 526 465 891 1022 428 As know am big advocate theoreti cal Sailplane performance analysis Lee John Hohensee developed market computer Sail plane design/analysis programs called PC-Soar MaxSoar BB Part quest tie theory reality analysis actual flight per formance Al Scidmore Professor Electrical Engineering University Wisconsin pursuing instrumentation Sailplane digital data logger hope someday ALL STAINLESS STEEL HEAD LITE IItm BEST GLOW PLUG CONNECTOR Stainless Steel HEAD LOCK BEST DESIGN Welded No Solder Acid Flux Flexing Wires BEST NiCad Field Replaceable 12 AH SANYO 15 AH PANASONIC BEST QUALITY & GUARANTEE MODEL PRODUCTS CORPORATION BEST PRICESt #045-WIO NiCad Charger$ 995 available write directSt #040-With NiCad$ 1595 add $100 $200 outside US St #041-With NiCad & Charger $ 2595 MODEL PRODUCTS CORP PO Box 100 Allamuchy NJ 07820 201850-1508 December 1989 47 will able share some hard numbers Sailplane performance have calibration data first versions altimeter temperature sensor sup ply voltage monitor velocity sensor Al has some improvements under way altitude velocity Tbe equipment will small enough fit inside X-Country Scale ships can mounted pod above wing smaller models would nice transmit digitally encoded data ground someone would like get involved would love bear him Presently sensor outputs 0-20 VDC Drop line Lee Murray 1300 Bay Ridge Road Appleton WI 54915 phone 1-414/7314848 Lees letter reminder its good idea keep logbook Gliders Person ally usually dont note time flight enter date place number flights windspeed flying conditions weight ballast used results changes trim reason recording flight times during prac tice session maximum time launch objective Practice occasion perfecting pre cision landing one-minute countdown trying out different thermaling techniques general doing wild crazy things dont dare try during contest Id like review about practice sessions future column Please write youd like share favorite meth ods How-to-make-molds video previously re viewed two Julian Tamezs instructional videos titled Vacuum Bag Cut ting Foam Cores Now Ive chance see Julians 34-hr tape called Making Fiberglass Molds Let tell theres lot informa tion Julian partner Greg Norsworthy go through process making fiberglass fuse lage Cross-Country ship start making plug making fiberglass molds finally laying up two halves fu selage joining together whole pro cess takes good deal time involves lot skill tricks trade As Julian says tape gives ABCs making molds what equipment materials will need manufacture kind fiber glass part have idea youd like make own F/G fuselages guarantee studying tape will save much time aggravation kept returning thought watching Guys like Bob Sealy Jerry Slates really earn money make nice fuselages such reasonable prices three Julians tapes $3495 less 20% NSS LSF members plus $350 shipping address Channel Productions 19827 Bishops Gate Suite No1 Humble TX 77338 Phone 1-713/443-1253 days 5403944 evenings Sportsman Multi-Task update winner isMark Allens Falcon 880 course Im re ferring Jim Grays RIC Soaring Digest Chal lenge Design contest Sportsman Multi-Task SMT Sailplanes very interesting competition because good de signs entered including several brand-new ones says Soaring lacking new exciting things days addition winning Falcon 880 featured October column other designs en tered alphabetical order Bob Dodgsons Camano Terry Edmonds Callisto Don Chan ceys Conquest Don Edbergs Hustler Jeremy Teos Odyssey Bob Sealys Pulsar Paul Carlsons Quasoar Max Mills Westwind Sportsman Multi-Task new contest con cept Its takeoff F3B Duration/Distance Speed task flying restricted aircraft simplified flexible contest operation SMT suitable intermediate-level fliers say about LSF Level 3 designed middle ground between AMA Thermal Duration flying real International F3B Soaring competi tion limitation maximum weight SMT planes intended keep Gliders nonintim idating Sportsman-level fliers Thermal Duration will always bedrock Soaring USA youll find addi tion some Distance Speed tasks just adds fun makes quite different ball game Sailplane fliers say looking something new challenging think SMT will provide excitement seek ing restriction SMT planes must weigh 75 oz ballast pretty well excludes F3B planes permits just about kits market plus original de signs approximately two-meter 115-inspan size range Now suggested SMT contest rules place see October column have de sign RCSD jury feels good plane event next step clubs around coun try try SMT contests practice sessions see works club has run Distance Speed tasks before first problem will making 3 New ARFs ZMP SUKHOI Su-26M 1/5 ScaleIMPALA Masters Pattern span 68 area 890 sq motor 4 stroke 120 equivspan 66 area 800 sq motor 4 stroke 120 60 rear Preassembled lightweight epoxy fuselage sheeted plug-in wingsPresssembled balsa fuselage veneersd plug-in wings 8 stabs sheeted stab fin & rudder 5 dia epoxy cowl texan canopy &Epoxy cowl pipe cover removable canopy Illustrated illustrated assembly manualassembly manual see hobby dealer order direct MONARCH AMA Sport Pattern span 66 area 750 sq motor 4 stroke 90 60 Cu Preassembled balsa fuselage venesred wing shaped balsa parts texan canopy epoxy cowl illustrated assembly manual c ZIMPRO MARKETING tu sOt arK OAK StOOL 55 35535 P001St 515 482 6155 48 Model Aviation AIR WOLF EPOXY FIBERGLASS FUSELAGES TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $21000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 Z ial Introductory Offer Frequency Conversion $3500 Includes Crystals Certification Special Fast Turnaround Now Available CALL Send Large Self Addressed Envelope Brochures UPS U S Mail Federai Express Used Mastercard Visa Accepted pair sighting devices used define two dimensionless planes 150 meters apart known Base Base B two bases just big windows sky delineate distance Glid ers need fly leg Speed Distance circuit RMSA PPSS clubs Colorado fly quite bit Distance club contests weve found hoop-on-a-tripod sighting device both simple make easy use first described Dan Pruss June 1983 Soaring column thismagazine dont save old sues MA send business-size envelope 25C stamp Ill return reprint Dans column showing make sighting device quick description Pruss sighting device 36-in length %2 music wire stuck holes drilled opposite sides plastic like Lucite metal block about 15 20 side A-in hole drilled precisely 900 %2 holes Through hole inserted 10in length A-in-GD brass tube bottom block drilled No 7 drill tapped x 20 attachment camera tripod operation set up sighting device near winches Base walk 150 meters upwind F3B crosswind AMA rules set down other sighting device Base B just look through brass tube sight Base device adjust ing head tripod Doing same thing Base Aie sighting Base B deviceguarantees wire hoops both bases exactly parallel other Necking down end brass tubes soldering short pieces two-nextsmaller-size tubes makes sighting process precise look through big end 150-meter distance can laid out measured length cable fishing leader stored fast-wind spool Just play out walk Base B wind up walk back whole procedure can done faster setting out winch Speed task run flier time flagger required Base B flag ger puts up flag Glider about half way Base B drops Glider breaks plane defined wire hoop flag must stay up Glider fails break planeie cuts turnso pilots timer can tell him go back try again timer usually calls Base turns pilot pilot needs stand near timer Base sighting device practice its best pilot get lined up Base can judge turn himself instead waiting Turn call Distance task usually run four pi lots flying man-on-man although can done time small contests needs flagger differently colored flag Base B plane four planes per heat youll need flaggers red white blue green colored flags course need establish before launching color signed pilot Holding up red white blue green flag also holding up Glider helps Base B crew determine plane flag Also weve found inex pensive Radio Shack-type two-way radio set very helpful communicating back forthISO meters just bit too far shouting As mentioned above first time two flying SMT need called contest Its good schedule couple practice sessions everyone gets hang flying Speed Distance tasks well getting accustomed flagging jobs Give try Please let know works out Airfoils Low Speeds title 398-page book Michael Selig John Donovan Da vid Fraser reporting long-awaited results tests using Princeton Universitys lowspeed wind tunnel book being published Herk Stokely Soartech #8 sells $20 ppd may order now Herk 1504 Horseshoe Drive Virginia Beach VA 23451 Princeton tests probably exten sive best controlled investigation model Sailplane airfoils ever done As such Sailplaners have extremely anxious read about what Michael John Dave have discoveredand some new super airfoils will forthcoming So Soartech #8 should very interesting popular read David Fraser also designer popular Sailplane Design computer program lat est Version 30 has Princeton data cludes 87 airfoils including flapped tripped versions David says Its quite gold Version 30 sells $35 Version 2 users can updated 30 returning diskette $10 Write Sailplane Design 1335 Slaton Dr Maple Glen PA 19002 Torrey Pines Scale Fun Fly Its short notice over Thanksgiving weekend Friday through Sunday Torrey Pines Gulls club will put Scale-only Slope Fun Fly fa mous Torrey Pines site just north San Diego Charley Morrey Slope Soaring News wrote invite Scale fans come fly Charley said details hadnt nailed Continued page 156 December 1989 49 Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royal Tower Hobbies World Engines Spectrum Analyzers CalIbrated Test Instruments Large Inventory RIC Parts Crystals THE PIPER BRAVE scale model Pipers latest Ag plane t wing span 30-33 lbs 5 cc power lb payload ational flaps hopper door onal Spreader Kit formed aluminum landing gear rglass cowls um-formed canopy tucted extruded foam ply hardwood E $269~ OPTIONAL $ 4fl95 Smoker l actually dusting KITSPREADER SEND $100 FOR CATALOG OFQ 4/RT 1 NEODESHA KS 66757 SAC KITS AND ACCESSORIES316 325-2821 Free Shipping Kit OrdersScott Airplane CompanyVISA/MASTERCARD GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation
Edition: Model Aviation - 1989/12
Page Numbers: 44, 45, 46, 47, 48, 49, 156
NEAT constant-tension winch Jack Perecman Golden Valley MN sent excellent photos very neat winch Jacks letter tells about Enclosed will find some photos showing constant-tension winch designed built winch presently its second season far has proven quite reliable Im mem ber Minnesota RC Soaring Society have used winch both club fun-flys contests motor starter motor Johnson outboard has high torque plus ad vantages both long shaft thread end splines near motor face make mounting drum quite easy photo shows winch turnaround transportation mode Another photos shows right side winch its operating position wheels have flipped out underneath frame now resting ground foot treadle behind attached winch means bicycle brake cable operation farther treadle pushed down greater tension line T handle device top battery emer gency kill switch threaded rod crank low motor pivots motor/drum assembly fine adjustment line level winding final photo shows main parts constant-tension device Pushing down foot treadle pulls cable causes switch arm pivot counterclockwise away spring-loaded roller arms microswitch normally closed As soon switch pulled away roller arms closes en ergizes solenoid supplies power motor As tension line increases roller arms begin pivot toward switch ten sion line counterbalanced two springs desired tension achieved left roller arm touches microswitch open ing turning off solenoid will stay off until tension line decreases greater tension desired operator pushes foot treadle down pulls switch farther away roller arm springs have stretched before arm contacts switch operation due dampening effect stretch line way device automatically pulses motor off very similar what operator would using normal foot switch Other features include one-way clutch roller can engaged disengaged moving 44 Model Aviation Radio Control Soaring Byron Blakeslee 3134 N Winnebago Dr Sedalia CO 80135 Four Ts Teutonic Tailless Terror Team Germany flew Viking Cup Slope Races held Denmark Note models has some sort experimental aftmounted horizontal stability augmentation surface model just front has extended fu selage central fin other wings use tip-mounted fins Photo Preben Norhoim Swiss team Viking Cup meet Manager RoIf Gersberger right Norholm Jack Perecman designed winch its constant-tension mechanism Motor starter Johnson outboard motor Jack en gineer 3M company designs sort thing living Items note T-handled kill switch mounted right bat tery terminal extra-heavy battery post clamps flip-up wheel carriage Foot treadle gas pedal tells winch much tension put towline winch motor cycles automatically maintain desired tension Author Blakeslee has info column small black lever seen just above center shaft clutch roller uses Torrington oneway roller bearing addition just below roller mounted roller arm small tri angular piece urethane rubber rubs rim drum effectively brakes drum slightly prevent backlashes main purpose building winch first see simple reliable constant-tension device could built F3B competition days weak link Second perhaps applicable average club putting stop switch arm possible easily ad just maximum tension pilot can achieve using winch have able launch Gnome hand-launched Glider immediately readjust winch launching Windsong addition possible beginners have con fidence launching airplanes fear folding wings can see what beautiful job engineering fabricating Jack did winch especially constant-tension device CT mechanism would course work winch just Jacks outboard-motor design Some careful machinework would need done duplicate though Jack said hed make drawings avail able theres enough interest can con tact Jack Pereeman 224 Natchez Ave North Golden Valley MN 55422 Incidenially winches should have kill switch similar Jacks cut off battery power case emergency common situ ation stuck solenoid tries strain plane through turnaround need switch can operate quickly state severe panic RV shops sell big copper knife switches about $20 mount right battery post Theyre cheap insurance Danish connection risk infringing Mark Triebes turf Id like print letter friend Preben Norholm Copenhagen describing 1989 Viking Cup Race Vi king Cup biggest annual International F3F event held North Sea slopes near Hanstholm Denmark last June F3F FAI Provisional event Slope Racers fly 10 laps 100-meter course against clockone plane time Slope Racing US traditionally run exciting way te wtth four planes flying against other heat However Europeans decided certain prospect midair collisions consequent loss hundreds dollars worth planes equipment sufficient rea son race one-at-a-time Preben founders F3F Racing justifiably proud success Viking Cup has achieved Preben too beauty event like gathering gether enthusiasts different coun tries Preben would like US fliers participate too team South Bay club got serious thinking stage couldnt quite man age trip 89 Maybe next year Isnt wonderful have hobby/sport can travel almost country world welcomed instant friends identical interests Prebens letter ended up 40 contestants coun tries spread Iceland Israel almost everything between came Switzer land Bavaria Berlin Westphalia Osnabruck area England Scotland Norway Nic Wright England won again Denmark took team trophy followed England NorIv finest model building equipment manufactured kahe4 zfloS4loAuh1wi 4ohrk a41/i/nna 94eady& Mdc dealer order direct-500A Magic Magnet Builder Icontains 16x48 Steel Base Plate 30 Magnets 10 stands S 9450 SOOB Master Magic Magnet Builder Icontains 1 6x4B Steel base plate 60 Magnets 20 stands 10 Vert press 10 steps 20 rib holders 50 sets nuts & bolts$16895 503B Base Plate Extension 1 6x1 6 Steel Base plate building giants$ 2695 501A Unassembled Magnets 10 pak$ 1195 501 B Assembled Magnets 10 pakS 2200 502 Stands 110 uprights primarily fuselage easyS 950 504 Vertical press 5 pak holding spars leading trailing edges position$ 995 505 Steps 5 pakl adjustible leading & trailing edge positioning$ 595 506 Rib Holder 10 pak Use magnet building faster$ 995 ~TUFELDON J LIND COMPANY 3151 Caravelle Dr Lake Havasu City AZ 86403 C 16021453 7970 Send sell addressed stamped envelope catalog ot products M/C & Visa accepted December 1989 45 Fourmost Fuselage Fixture Mark II Fourmost Fuselage Fixture Mark II designed auto matically align fuselage structures built strings measuring eyeballing Price $5995 Simply slide four centering brackets track until align fire wall tail joint two bulkheads Clamp fuselage together lightly rubber bands structure will straight ready gluing Fixture will accomodate fuselages long four feet wide eight inches eight inches Please include $400 br Shipping Handling direct orders FOURMOST PRODUCTS 4040 24TH AVEFOREST GROVE OR 971165031 357-2732 WHEN YOU FORGET\OUR UNITS REMEMBER RC System NiCd Batteries Ihe chargers YOU need packageFor Cycier-Chargec,,,, $23996 Fits 48V Rs 96V Tx packsPlus ened Ceii Others avaable write kier.. *3495Reguiar Modei $4696 ForPlus $3 S&H\ eiFor held kit smatPlus $3 S&H tipleelectric boat batteriesSpecify 612 24V Heavy Duty Model.. $5896 sport winch large boat andPlus $4 S&H electric power charging batteriesSpecify 6 1 2V CaRa Products ox 221 DealerinqurneslnveedCanton SO 57013 pp THERMAL CHARGER what looking electric sailplane good looks easy build fun fly great performance Thermal Charger Wing Span Wing Area Motor Included 60 Inches 545 Sq Inches Leisure 05 Electric C — t PRECISION PRODUCTS INC 714 592-5144 510 E Arrow Highway San Dimas CA 91773 way first day just little wind ran practice round let fliers prac tice own afterwards needed especially Alps because unfamiliar seaside slopes winds second day shot four good contest rounds fairly good west wind third day rather weak winds did round Some fliers went sight seeing some stayed practice fourth day expected good north winds finally arrived 12- 20-mph winds directly best slope made five rounds dinner delayed until 800 pm Rain forecast next day turned out expectedan off day kept people busy think happy time Evening entertainment included RoIf Girs berger designer RG series airfoils new Chairman FAI s F3B ClAM Subcom mitteeBB telling about airfoil develop ments showing Selig-Donovan Princeton wind tunnel video several times very popular conference about F3F rules future Viking Races took two hours de cide rules great meet again Derbyshire England October 1990 RoIf also showed two films about modeling full-scale gliding Switzerland 1942-44 100% professionally done included some unique things films original purpose PR Swiss Army Air Force long rainy day off Chas Gardner Brian Sharp England Scotland told about British Slope Cross-Country Racing ended 20-minute presentations six interesting thought planes entered contest pilots plus sometimes interpre ter Very popular too course pilots se lected very proud have opportunity tell about marvelous designs 'Then time get dressed banquetand long happy night special Viking Year award went Siegfried Schedel Bavaria Siegfried started out looking very much like beginner F3F practiced minute could find climbed steadily scoreboard ended fifth place beating 80% winning Danish team agreement best man won no protests during contest Includ ing practice must have close 1000 flights two three models minor damage landings com pletely repaired hour 'The next morning everybody packed went home again Anna Johannes owners Vigso Bugt Pension everyone stayed BB happy too said never better guests wished us come back soon hope will have success new American Sportsman F3B class dont know told fact F3B contests Denmark according local Sportsman rules far biggest problem num ber officials needed So decided cut down simply taking five steps 1 Eliminating Distance task altogether 2 Fly Duration task individual flights after another no group scoring 3 No working-time slots 4 Organizer-supplied winches 5 Only attempt flight tough pop off Its far simpler contest run because everybody can help another same way normal American Duration-only contest challenge airthe six-minute Preci sion Speed runis exactly same real F3B course guys would have liked fly Distance no way can make work Three weeks ago ran National Cham pionship F3B have separate Nats classes F3A F3B F3C etc 18 pi lots zero officials fixed se quence flying timekeeping flagging etc CD himself managed place second course way setting up will produce some breaks since people active time lunch break must put managed seven rounds two days including early dinner Sunday night Italian pizza res taurant everyone 15 50 years great fun Next weekend will busy practicing F3B team Paris Preben Danish teams managerBB have good team time mean have some bright young people team gonna win anything down Paris certainly will middle time team does have strongest men eitherthe members spread second tOth place Nats will survive physi cally mentally hope will learn some thing can used Czechoslovakia next year 1990 European F3B Championships Netherlands -1991 F3B World Championships Only has made Speed task better 18 seconds official contest dont count practice runs arrive Paris day before practice round would have liked few days 46 Model Aviation durable skis made lightweight aluminum feature steel spring holds ski rigid flight also elevates axle above ski no modifications cur rent gear wire needed can go wheels skis seconds side ski also has special edge allows excellent tracking icy surfaces avalisbie three sizes snd can purchased trikes just mains order please send check money order $200 shipping handling Add 8% sales tax Minnesota Allow 2 weeks delivery large scales please submit weight wing span Telephone inquires call Ron 612-781-7333 NORTHERN 20 30 Trike $2000 Mains $1500 MODELING 40 60 Trike $2200 Mains $1700 PRODUCTS Large Scale Trike $7500 Mains $5500 PO Box 21181 ColumbIa Heights MN 55421 781-7333 DIAMOND ShARPENS BLADES NA JIFFY GET GREAT EDGE ON THAT NO11 OR UBER SKIVER BLADE COMES WITH REVERSIBLE BLOCK 325 grit 1000 grit $1500 Replacement Block$850 ADD $175 P&H 6% sales tax CA AVAILABLE CERAMIC AND ARKANSAS WHETSTONES P 0. BOX 8 MOORPARK CA 93020 805 529-9313 short money time again Prebens letters always fun read full good information great time Preben 1987 following Osnabruck F3B World Champs staying same pension flying same slopes talked ahout wind north-facing bluff high above beach cant imagine finer place Slope flying once wrote bluff must 400 ft high Preben later called attention fact highest spot Denmark 350 ft still say looked high time remarks about fly F3B con tests could food thought US CDs run ning Sportsman multitask events Because no hard-and-fast rules can run SMT contests way makes sense local conditions Wingspan winch launches windspeed Wisconsins Lee Murray kind enough write share some interesting data proj ect has working Back 1986 several Sailplane fliers club began collect records flights IIIBTBI2IIN 11$ ELIcIT tITlES PndlgJ II HIngE. 33-3344-1346-774 Ill MItag learn about performance various mod els effects flying conditions etc records now include over 250 flights provide some insight flight performance related windspeed launch methods Sailplane type Virtually flights club field sod farm often damp compared higher ground evaporative cooling often limits thermal generation Location would important consideration comparing results tween clubs Winch launches using Two-Meter Prodi gy resulted flights 25 seconds longer av erage high-start widely recognized difference performance between wingspans also evident shown chart below AWRACE FLIGHT TIME VT HIIECSPHN 336 FlIght Histopa ii isA N1a Aa 3p 4 TIHH IN iI121IN146SB WII4GNFBS PPndlgyB 50-4 B CopiloA comparison theoretical flight times suggests effect involves differ ences sink rate difference between 2M Standard class 78 vs 100 larger difference between Standard Unlim ited Class 2M class RO-8 has old standby years E-205 wing pro file substituted performer Prodigy shows up also Flying moderate wind does decrease flight times based Prodigy flying off highstart chart titled Flight Times vs Windspeed shows relationshipwhich fact undoubtedly linear lack data shown linear Flight lAment WinO Spa. Pndlns-IhIhnlapt Sa N6 Ia N 3 lend Spend reason flight times appear correlated windspeed probably related getting height launches since winch flights did show same correlation Model & Average Flight Times Minutes 2-Meter Prodigy RO-8 Std Class Cumic XC/Unlimited Dynasoar Scale ASW-17 526 465 891 1022 428 As know am big advocate theoreti cal Sailplane performance analysis Lee John Hohensee developed market computer Sail plane design/analysis programs called PC-Soar MaxSoar BB Part quest tie theory reality analysis actual flight per formance Al Scidmore Professor Electrical Engineering University Wisconsin pursuing instrumentation Sailplane digital data logger hope someday ALL STAINLESS STEEL HEAD LITE IItm BEST GLOW PLUG CONNECTOR Stainless Steel HEAD LOCK BEST DESIGN Welded No Solder Acid Flux Flexing Wires BEST NiCad Field Replaceable 12 AH SANYO 15 AH PANASONIC BEST QUALITY & GUARANTEE MODEL PRODUCTS CORPORATION BEST PRICESt #045-WIO NiCad Charger$ 995 available write directSt #040-With NiCad$ 1595 add $100 $200 outside US St #041-With NiCad & Charger $ 2595 MODEL PRODUCTS CORP PO Box 100 Allamuchy NJ 07820 201850-1508 December 1989 47 will able share some hard numbers Sailplane performance have calibration data first versions altimeter temperature sensor sup ply voltage monitor velocity sensor Al has some improvements under way altitude velocity Tbe equipment will small enough fit inside X-Country Scale ships can mounted pod above wing smaller models would nice transmit digitally encoded data ground someone would like get involved would love bear him Presently sensor outputs 0-20 VDC Drop line Lee Murray 1300 Bay Ridge Road Appleton WI 54915 phone 1-414/7314848 Lees letter reminder its good idea keep logbook Gliders Person ally usually dont note time flight enter date place number flights windspeed flying conditions weight ballast used results changes trim reason recording flight times during prac tice session maximum time launch objective Practice occasion perfecting pre cision landing one-minute countdown trying out different thermaling techniques general doing wild crazy things dont dare try during contest Id like review about practice sessions future column Please write youd like share favorite meth ods How-to-make-molds video previously re viewed two Julian Tamezs instructional videos titled Vacuum Bag Cut ting Foam Cores Now Ive chance see Julians 34-hr tape called Making Fiberglass Molds Let tell theres lot informa tion Julian partner Greg Norsworthy go through process making fiberglass fuse lage Cross-Country ship start making plug making fiberglass molds finally laying up two halves fu selage joining together whole pro cess takes good deal time involves lot skill tricks trade As Julian says tape gives ABCs making molds what equipment materials will need manufacture kind fiber glass part have idea youd like make own F/G fuselages guarantee studying tape will save much time aggravation kept returning thought watching Guys like Bob Sealy Jerry Slates really earn money make nice fuselages such reasonable prices three Julians tapes $3495 less 20% NSS LSF members plus $350 shipping address Channel Productions 19827 Bishops Gate Suite No1 Humble TX 77338 Phone 1-713/443-1253 days 5403944 evenings Sportsman Multi-Task update winner isMark Allens Falcon 880 course Im re ferring Jim Grays RIC Soaring Digest Chal lenge Design contest Sportsman Multi-Task SMT Sailplanes very interesting competition because good de signs entered including several brand-new ones says Soaring lacking new exciting things days addition winning Falcon 880 featured October column other designs en tered alphabetical order Bob Dodgsons Camano Terry Edmonds Callisto Don Chan ceys Conquest Don Edbergs Hustler Jeremy Teos Odyssey Bob Sealys Pulsar Paul Carlsons Quasoar Max Mills Westwind Sportsman Multi-Task new contest con cept Its takeoff F3B Duration/Distance Speed task flying restricted aircraft simplified flexible contest operation SMT suitable intermediate-level fliers say about LSF Level 3 designed middle ground between AMA Thermal Duration flying real International F3B Soaring competi tion limitation maximum weight SMT planes intended keep Gliders nonintim idating Sportsman-level fliers Thermal Duration will always bedrock Soaring USA youll find addi tion some Distance Speed tasks just adds fun makes quite different ball game Sailplane fliers say looking something new challenging think SMT will provide excitement seek ing restriction SMT planes must weigh 75 oz ballast pretty well excludes F3B planes permits just about kits market plus original de signs approximately two-meter 115-inspan size range Now suggested SMT contest rules place see October column have de sign RCSD jury feels good plane event next step clubs around coun try try SMT contests practice sessions see works club has run Distance Speed tasks before first problem will making 3 New ARFs ZMP SUKHOI Su-26M 1/5 ScaleIMPALA Masters Pattern span 68 area 890 sq motor 4 stroke 120 equivspan 66 area 800 sq motor 4 stroke 120 60 rear Preassembled lightweight epoxy fuselage sheeted plug-in wingsPresssembled balsa fuselage veneersd plug-in wings 8 stabs sheeted stab fin & rudder 5 dia epoxy cowl texan canopy &Epoxy cowl pipe cover removable canopy Illustrated illustrated assembly manualassembly manual see hobby dealer order direct MONARCH AMA Sport Pattern span 66 area 750 sq motor 4 stroke 90 60 Cu Preassembled balsa fuselage venesred wing shaped balsa parts texan canopy epoxy cowl illustrated assembly manual c ZIMPRO MARKETING tu sOt arK OAK StOOL 55 35535 P001St 515 482 6155 48 Model Aviation AIR WOLF EPOXY FIBERGLASS FUSELAGES TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $21000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 Z ial Introductory Offer Frequency Conversion $3500 Includes Crystals Certification Special Fast Turnaround Now Available CALL Send Large Self Addressed Envelope Brochures UPS U S Mail Federai Express Used Mastercard Visa Accepted pair sighting devices used define two dimensionless planes 150 meters apart known Base Base B two bases just big windows sky delineate distance Glid ers need fly leg Speed Distance circuit RMSA PPSS clubs Colorado fly quite bit Distance club contests weve found hoop-on-a-tripod sighting device both simple make easy use first described Dan Pruss June 1983 Soaring column thismagazine dont save old sues MA send business-size envelope 25C stamp Ill return reprint Dans column showing make sighting device quick description Pruss sighting device 36-in length %2 music wire stuck holes drilled opposite sides plastic like Lucite metal block about 15 20 side A-in hole drilled precisely 900 %2 holes Through hole inserted 10in length A-in-GD brass tube bottom block drilled No 7 drill tapped x 20 attachment camera tripod operation set up sighting device near winches Base walk 150 meters upwind F3B crosswind AMA rules set down other sighting device Base B just look through brass tube sight Base device adjust ing head tripod Doing same thing Base Aie sighting Base B deviceguarantees wire hoops both bases exactly parallel other Necking down end brass tubes soldering short pieces two-nextsmaller-size tubes makes sighting process precise look through big end 150-meter distance can laid out measured length cable fishing leader stored fast-wind spool Just play out walk Base B wind up walk back whole procedure can done faster setting out winch Speed task run flier time flagger required Base B flag ger puts up flag Glider about half way Base B drops Glider breaks plane defined wire hoop flag must stay up Glider fails break planeie cuts turnso pilots timer can tell him go back try again timer usually calls Base turns pilot pilot needs stand near timer Base sighting device practice its best pilot get lined up Base can judge turn himself instead waiting Turn call Distance task usually run four pi lots flying man-on-man although can done time small contests needs flagger differently colored flag Base B plane four planes per heat youll need flaggers red white blue green colored flags course need establish before launching color signed pilot Holding up red white blue green flag also holding up Glider helps Base B crew determine plane flag Also weve found inex pensive Radio Shack-type two-way radio set very helpful communicating back forthISO meters just bit too far shouting As mentioned above first time two flying SMT need called contest Its good schedule couple practice sessions everyone gets hang flying Speed Distance tasks well getting accustomed flagging jobs Give try Please let know works out Airfoils Low Speeds title 398-page book Michael Selig John Donovan Da vid Fraser reporting long-awaited results tests using Princeton Universitys lowspeed wind tunnel book being published Herk Stokely Soartech #8 sells $20 ppd may order now Herk 1504 Horseshoe Drive Virginia Beach VA 23451 Princeton tests probably exten sive best controlled investigation model Sailplane airfoils ever done As such Sailplaners have extremely anxious read about what Michael John Dave have discoveredand some new super airfoils will forthcoming So Soartech #8 should very interesting popular read David Fraser also designer popular Sailplane Design computer program lat est Version 30 has Princeton data cludes 87 airfoils including flapped tripped versions David says Its quite gold Version 30 sells $35 Version 2 users can updated 30 returning diskette $10 Write Sailplane Design 1335 Slaton Dr Maple Glen PA 19002 Torrey Pines Scale Fun Fly Its short notice over Thanksgiving weekend Friday through Sunday Torrey Pines Gulls club will put Scale-only Slope Fun Fly fa mous Torrey Pines site just north San Diego Charley Morrey Slope Soaring News wrote invite Scale fans come fly Charley said details hadnt nailed Continued page 156 December 1989 49 Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royal Tower Hobbies World Engines Spectrum Analyzers CalIbrated Test Instruments Large Inventory RIC Parts Crystals THE PIPER BRAVE scale model Pipers latest Ag plane t wing span 30-33 lbs 5 cc power lb payload ational flaps hopper door onal Spreader Kit formed aluminum landing gear rglass cowls um-formed canopy tucted extruded foam ply hardwood E $269~ OPTIONAL $ 4fl95 Smoker l actually dusting KITSPREADER SEND $100 FOR CATALOG OFQ 4/RT 1 NEODESHA KS 66757 SAC KITS AND ACCESSORIES316 325-2821 Free Shipping Kit OrdersScott Airplane CompanyVISA/MASTERCARD GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation