Free Flight: Duration

NEW materials like other change bring new problemsand new possibilities tech nology Free Flight wing construction chang ing rapidly Its hard keep up whats hap pening composite construction carbon fiber Kevlar other new materials techniques course can bury head sand keep building way have last 30 years Bus before take look some ways can incorporate some new materials techniques models building might pleasantly sur prised new structural techniques actu ally easier quicker conventional balsaand-tissue structures result will wing thats stronger stiffer warp re sistant advent zoom launch struc tural demands Nordic Glider wing have creased greatly Using conventional balsa spruce tissue construction oniy way increase strength stiffness add piec es last Nordic built Ekhtenkovs 1973 win ner well over 300 pieces wood wing Thats lot cutting fitting gluing No wonder serious FlA fliers trying come up better wings also easier quicker build Three-time US FF team member Jim Bradley Orlando has fine-tuning structure 1987 model year latest wings Nordic combine balsa spruce foam car bon fiber Heres Jim does First builds up ta pered spruce carbon-fiber spar jig cuts piece foam planform shape half-inch shorter desired panel length foam blank epoxied front spar leading edge two airfoil-shaped A-in balsa end ribs epoxied ribs capped 003 carbon fiber sheet act guides Jim hot-wire cuts foam airfoil shape leading edge piece x 3/6-in balsa set vertically stiffen rather small leading edge Jim adds 007 carbon fiber back bottom form L After foam cut shape Jim covers foam /2 oz carbon fiber matte youre familiar stuff looks like black silkspan Since matte rather stiff Jim cuts approximate size creases down middle leading edge coats spray adhe sive attaches foam lapping over spar trimming flush rear face spar strengthen matte Jim brushes two coats Titebond glue diluted equal part water has proved much lighter epoxy plenty strong rest wing Jim uses fairly conThree-view Alexandre Andrujkovs Fl B Wakefield taken Soviet aviation magazine Wings Fatherland shows workings variable-pitch propeller Pylon houses variable-washout wing wiggler beeper multifunction clockwork timer autostart 101mmI5 S@KOLOv nOVipIID #IWIflWI1OY. . ... aO 45 1iQ Im . -. Ovrnqs dK CF lStitt 5Botm idt ri1ht wing polvsryrien foam45100mm 4 440 nim lQo / 45240 lAs 90 4zf0I4t50I1X4S0i455l0/IXS5O 4t50145A0012x 420 op sd idfntieaL Leo Reynders Fl wing construction February/March issue Frances Vol Libre foam carbon fiber epoxy glass cloth US modelers can subscribe Vol Libre through Peter Brocks 313 Lynchburg Dr Newport News VA 23806 price $18 per year ventional built-up balsa structure few good twists Before assembly Jim adds vertical piece 007 carbon fiber front face trailing edge strip stiffen After wing assembled Jim adds cap strips thinner 003 carbon fiber top bottom ribs way Ive tried last two techniques couple Wakefield wings added stiff ness amazing Weight gain wings few grams adding cap strips took couple hourswell worth Jim covers wings usual tissue dope Titebond coating carbon fiber matte enough keep dope attacking foam Jim feels foam carbon fiber D-box construction much quicker build conventional balsa-ribs-and-sheeting D-box adds new wings stronger cau tions have careful will end up heavier conventional construction next pair wings will use three-ounce carbon fiber cloth $50 yard instead matte Ive watching Jim fly dozen years Ive notedand copiedhis use carbon fiber As Jim says models keep getting blacker blacker should also add t ter better need carbon fiber sheet matte contact Jim Bradley Model Products 1337 Pine Sap Ct Orlando FL 32825 Like sources exotic Free Flight good ies Jims operation strictly sideline sure include stamped self-addressed enve lope write Jim also makes excellent circle-towhook electronic timer want get started Towline write Jims catalog Much new technology wing construc 68 Model Aviation Free Flight Duration Louis Joyner 3657 Bmokwood Rd Blnningham AL 35223 ThETh ___I, t U US USSPIIU kt-UU U SOWIJI UU 41U1JUMU mu. IB II Ia tion involves use foam cores covered some sort skin stiffen everything up Ron St Jeans structureless foam composite SFC construction method uses foam covered silkspan painted diluted wood glue ex tra strength adds layers silkapan center method detailed April 1982 issue Model Aviation California Nordic fliers Martyn Cowley Jim Wilson have adapted construction tech nique adding sturdy spar substituting gift wrapping paper silkspan wallpaper paste white glue wings very stiff could probably use suriboards decorating potential wrapping paper mind-boggling stabs rudders use Japanese tissue over foam Throwing ideas vat stirring bit can come up some interesting pos sibilities about using foam core hardwood carbon fiber spar covering front portion carbon fiber matte give D box effect back two-thirds wing could covered silkspan tissue A-oz Kevlar matte stabs tip panels 1/16 sheet Mi-depth spar could let foam car bon fiber strips added top bottom extra stiffness could use either carbon fiber sheet carbon fiber tows use tows Titebond could used stead epoxy attach foam word caution cyanoacrylate instant glues lot other stuff dope thinner epoxy paint gasoline melt foam Always test first Last winter played around some Wake field stabs using few techniques re sults encouraging unfortunately ran out time resort conventional struc tures order get two new alrplanes ready spring problem noticed Kevlar car bon fiber mattes fuzz up quite bit coated Titebond asked Jim Bradley handles problem Nordic D-boxes said sanding knocks down roughness covering tissue results smooth finish pointed out need allow thickness matte lay ing out wing section templates Covering type structure tissue QfcD 32ALL~ 3929 Extruded polystyrene sold under several brand names Two common Styro foam blue foam FoamulaR pink foam Density blue foam around 17 Continued page 153 Y51/c{ O/VF43j Switzerlands Francois Tapemoux uses auto-stab mechanism Wakefield alu minum post held down during flight released DT Vol Libre drawing Neat simple dope solves other problem water proof wing since Titebond will dissolve water St Jean covers wings plastic freezer wrap Cowley Wilson use shel lac Getting set up cut foam surprisingly easy bow assembled scrap 1 x 2s arm pivoted An old Coupe dHiver rub ber motor stretched between cup hooks kept Sig nichrome wire tight power used threeamp automotive battery charger worked out just about right need sort voltage regulator guiding hot wire /16 plywood will work plastic laminate better formation foam cutting see Master Modeling available local hobby shop AMA Another good book Composite Con struction Home-built Aircraft also available AMA Although geared full-sized air craft theres lot good information foam carbon Kevlar epoxy thats use Free Flight modeler Once get set up cutting foam incredibly quick Tapered wings just easy straight ones can build washout washin Cutting thin trailing edges can tough try cutting front back sure include some runoff leading edge trail ing edge airfoil guides way hot-wire technique great making airfoilshaped jigs building undercambered wings Now crash course foams themselves two types polystyrene foams readily available expanded extruded Both used insulation building construction check local building supply companies look Yellow Pages under insulation white beaded foam expanded polystyrene also commonly used beer coolers electronics packaging stuff light about 13 lb/cu ft rather weak crumbly September 1988 69 Vol Libre editor Andre Schandel put together book plans 1987 FF World Champs Its available $10 Knoxville TN Free Flighter Georgia Tech graduate Stan Smith awaits good air low-tech P-30 event offers good con trast FAI events Stan Smith photo IPAVEYYSTEMS LucifER 075 HYPERIHRUSI motor fused switch harness propeller adaptor 8/ 4 fibreglass propeller LUCIFER has computeroptimized E-193 airfoil superb L/D tremendous speed range ideally suited fliers because its inherent stabilily enough flat-boffom wing floaters barely stagger up a___________________ couple hundred feet Build LUCIFER enjoy performance expect Big enough fly like sailplane should small enough repeatedly climb Pin-Head altitude baffery charge Pre-cut fuselage sides accurate die machine cut selected woods complete rolled plans hardware detailed instructions piece wing spruce spars strength simplicily building IIAVEY YSTEMS i oRPoRATIoN Special Combo Price 675 TOWER LANE WEST CUES TER PA 19380 215-430-8645 plied Popsicle stick craft stick hobby craft people call irRMcM smoothed out sands like dream dry adds little extra weight Hats off New Mexico Free Fliers have good old-fashioned approach running club including super newsletter active involvement Junior programs terested learning about what going part great Southweat get touch Ann Earl Eckerson spark plugs outfit 810 Baird Circle Aztec NM 87410 Great job FF Duration/Joyner Continued page 69 lb/cu ft pink stuff comes several weights FoamulaR 150 about 15 lb/cu ft FoamulaR 250 about 18 company has re cently introduced low-density foam FoamulaR LDA density 13 lb/cu ft under stand Styrofoam makes gray foam thats about 15 lb number European modelers combin ing foam glass cloth epoxy make molded wings Leo Reynders Belgium cuts Out wing blank foam uses waste pieces top bottom mold plywood web carbon fiber rovings soaked epoxy form spar Light fiberglass cloth laid out thin sheets polyester PVC film epoxy spread film put over bottom mold core added second layer film time epoxy-soaked glass cloth face downis put over core top form added whole mess vacuum-bagged pull mold down tight Squares balsa glued front edge help keep everything align ment see sketch Another popular European technique uses top bottom wing skins full-depth spar no ribs skin made thin typically 1mm Rohacell polyurethane foam top bottom skin covered light glass cloth epoxy would like try tech nique Rohacell available Aerospace Composite Products PO Box 16621 Irvine CA 92714 sell Rohacell 1 2 3mm thicknesses although dont list catalog Another increasingly popular construction tech nique FLC wings uses very thin hard alu minum skin over sheeted balsa wing Pioneered Russian Power flier 1987 World Champion Eugene Verbitski wings stiff smooth past getting hold 03mm aluminum has easy Some tales intrigue sound like something out spy novel midnight meetings whispered passwords dealings cashalways cash Lately aluminum has become more available although still definitely hobby shop item Basic construction involves cutting piece aluminum double-chord width epoxying top bottom balsa wing skins typically light /16 balsa adding ribs spar Finally top sheet bent back over ribs epoxied place Because dent ding shows up aluminum clean work shop must Also important cleaning aluminum using correct epoxy bond ing balsa aluminum New Orleans Power flier Doug Joyce re cently switched aluminum wing skins canard Lightning design uses three-step cleaning process First wipes aluminum al cohol lacquer thinner finally trichioroethylene careful stuffi vapors can harmful health Make sure work area well ventilatedand keep nose out vapor RMcM Doug uses paper towels makes pass liquid adhesive uses 3M 2216 gray structural ad hesive coats both aluminum balsa can find June 1986 issue Aeromo deller theres excellent article British Power flier Stafford Screen builds wings Ad ditionally 1988 NFFS Symposium editor Hermann Andersen has scheduled step-by-step photo story Sal Fruciano Randy Archers method aluminum wing construction Several other articles composite structures sched uled addition Archer article Check Fred Terzian NFFS Publications 4858 Moorpark Ave San Jose CA 95129 can order book much will cost Keeping track changes technol ogy sport Free Flight can quite chal lenge Part fun detective work necessary piece together bits informa tion something can use example Al exandre Andrujkovs fast-climbing Wakefield made quite stir last couple world championships certain details model found Three-views model have shown up several newsletters con struction details such things center gravity wing turbulators shown Also complicated variable-pitch prop hub detailed Finally found almost everything Rus sian general aviation magazine Kryl Ia Rodiny Wings Fatherland very detailed three-views reproduced Still missing September 1988 153 SIZED TO FLY AIR WOLF EPOXY FIBERGLASS FUSELAGE S TAKES MOST 50-60 MECHANICS OTHER MODELS AVAILABLE LARRY JOLLY MODEL PRODUCTS $20000 5501 WCOMO SANTA ANA CALIFORNIA 92703 714 826-6861 though information turbulators turned up Italian model magazine Modellist ica article about Anselmo Zens Rara Avis Wakefields way Andrujkov uses 4mm turbulator 42% chord best information CG location 55-60% column few years back review British FM sym posium Wings Fatherland interesting publication no ads Russian course magazine covers everything skydiving aviation history Free Flight coverage includes both detailed plans state-of-the-art FM models beginners column done cartoon-style spotted Wakefield motor test general modeling magazines around world also include occasional Free Flight item few publications cover Free Flight exclusively addition NFFS Digest British monthly newslet ter Free Flight News typical issue includes sev eral three-views technical article two con test results roundup available supplies Contact Ian Kaynes 7 Ashley Road Farnbor ough Hants GUl4 7EZ England Another such publication French bi monthly Vol Libre now its eleventh year Edi tor Andre Schandel obviously puts lot work publication Last year honored special NFFS award typical 60-page sue will include several three-views maln FM categories well Coupe P-30 A-i fun includes Peanut two issue regular contributors 1937 Wakefield Champ Emmanuel Fillon evi dently has retired jumped Peanut vengeance Indoor also covered both Fl D beginner models Although written French English German translations few articles sue three-views easy understand no matter what language long familiar metric system French-English diction ary will help get through rough spots Actually part fun reading foreign magazines Aeromodeller translating American English example Danish magazine Modelflyve Nyt de lightful account Power flyoff 1987 Scandinavian International Thomas Koster vandt FiC-konkurrencen vedi tredie fly-off runde handkaste sin model til en flyvaing pa 2 sekunder Nummer Lothar Doring haude nemlig ikke nogen model flyve med i runden Very loosely translated someone knows absolutely no Danish says last fly-off round Lothar Doning didnt have model left Thomas Koster hand-glided Power model two-second flight take first place Whether call fritflyvning like Danes freiflug like Germans vol Ii bre like French Free Right great sport FF Old-Timers/Baker Continued page 70 great comfort However sometimes make models no competition use Somehow nice concerned competitiveness make something because like its looks have some nostalgic association have some other reason has nothing rational choice based performance potential Having said Ill now state next sev eral columns will concentrate selecting de signs performance potential struc tural modifications needed make last long enough reach potential see previous columnJuly 1988 want build Miss Philadelphia Quaker Red Zephyr power Su perbelchflre 60 let know can get out country before fly old cabin models small nonlifting stabs large fins short tail moment arms looked something like alrplane will fly pleasantly Brown Jr half-throttle power want get way up short engine run look ship longer tail moment arm shorter nose large stab lifting airfoil small fin lots dihedral Buzzard Bombshell does have lifting stab has everything else Within reason able limits will handle good 60 Super Cyke Ohisson Brown instead looping spiraldiving just goes up So will Brooklyn Dodger Sailplane Playboy Powerhouse Zipper Look size fins ships compared said will handle high power later Old-Timer era period accel erated development general really higher-performance models developed 1940-41 very few models designed earlier can match Interceptor Strato Streak Kerswap came out after fuselage cross section-rules dropped have lower drag add 154 Model Aviation VINTAGE -C PLAN CONSOLIDATED PBY-5A tCATALINA 9FT WING SPAN AlL RIBS B FULL FORMERS SHOWN ON PLANS11 PLAStIC ENGCOWLS $1090 PR CLEAR GUN BLISTERS $ 760 PR 4 LARGE PLAN SHEETS s $ 895 6FT WING SPAN MODEL POY-SA ENGINE COWLS $750 PR Plans $1495 GUN BLISTERS PR AOO $300 POSTAGE CATALOGOVER OPLANS $100 DEALERS WRITE WORLDWIDE SID MORGAN 13157 ORMONO BELLEVILLE 48111 USA