Fi Technicalities DOUBLE CHAMPION highly-com petitive sport model flying FF World Championships level makes con secutive winners rare breed Since Wakefield Cup initiated 1928 two individuals have honor Americas Joe Ehrhardt won cup 1930 1931 Finlands Arne Ellila FiB World Champion 1949 1950 Only FlA Glider started 1946 another consecutive winner Rudi Lindner Germany 1954 1955 No has managed feat FiC Power remarkable Ger manys Lothar Doring should join select group 1983 FF World Cham pionships Goulburn Australia Lothars performance truly outstanding reasons nations competing WCs early days field competitors considerably tougher rules have refined over years limit performance models technologically challeng ing ever Add adverse weather conditions experienced both Spain 1981 andinAustraliain 1983 youll realize Lothars performance indeed exceptional Lothar attended Goulburn Champs defending champion al lowed pole full time round himself Compared three team mem bers other poles may sound like advantage However con sider fact Lothar work alone preparing models spotting thermals retrieving can imagine no sequential order author takes another look 1983 FiB Wakefield Rub ber World Cham pionships emphasis unique ideas models saw EMartyn Cowley small task As conditions turned out very windy lots rain Lothar faced major task defending title Probably no could have better suited such challenge Flying skills aside Lothar individualist com petition style involves thorough advance preparation models equipment al lowing him single-mindedly concentrate two twin thermister wind record ing machines unit placed 50 yards upwind other comparative unit pole years win makes three times row such equipment used World Champion Itzhak Ben-Itzhak flew similar device win Taft CA 1979 December 1983 ClAM meeting tabled proposal ban such equipment future events wonder Lothar would have voted Such change would certainly alter emphasis fly Wake field modelwhich unarguably develop ing highly-sophisticated meteorolog ical event thought subject future FF Championships As top places closely fought often seconds separate gold silver bronze medalists wouldnt good idea future invite three back next WC defend titlesand keep individual winner company lonely pole Lothars models already well publi cized Espada 80/1 design selec ted National Free Flight Society Ten Models Year 1982 Anselmo Zen scramble re maining places Goulburn produced exciting finish half-dozen fliers contention right up last flight Con sistent maxing Hollands Anselmo Zen after second-round 247 proved re wards keeping ones head after early mistake Anselmo describes conditions kind weather found F 1 B contest unlike used northern Europe dont mean easyjust frightening confident mental approach vital success Cer tainly others psychologically frightened high wind conse quent damage could expected 64 Model Aviation Left nvlgorators small turbulators toward rear upper wing surface helped rough weather conditions including Anseimo Zen placed second Middle Hans Zachalmels wing wigglerdevice holds left wing trailing edge high give washout forthe initial six seconds power burst climb Right Wing tipletts used control tip vortices Wewy Zhang PR China placed fifth Rolled balsa boom 19% Stabaliser adjustable DTAuto Rudder hook below Mylar streamer pops out D T compartment recovery aid corn fields reinforced carbon fibre Carbon fibre motor tube 12 strand motor 20% stretch D T timer recess button centre motor C G plastic cover actsTimer start/stop Wing chines for extra lift Montreal stop R mechanism fully enclosed front end610 x 830 outrigger prop models compete effec tively WC level need prepared mentally able concentrate winning under adverse conditions model flew opening rounds uses Benedek B63566 airfoil thickened upper surface relatively few warps An auto-rudder comes 3 sec VIT 1 sec later Anselmos models also feature electric retrieval buzzer unusual Wakefield unit weighs 9 gin runs 15 hours best model damaged upon land ing very windy fourth round chose use older reliable model last flights As usual didnt look scoreboard towards end knew max planned take no risks sol changed wound motors 15 minutes waiting final flight Peter DeBoer assisting prevented launching until certain As rain started again put third motor waited Most fliers finished stood alone line No streamers left nor much time last minutes liberation came form good thermal told news after 3-mi flight scoreboard proclaimed second place New ideas teams experiment ing invigorators WC series turbulators positioned towards rear upper surface wingin addition conventional turbulator near leading edge subject intro duced modelers Martin Pressnell 1982 NFFS Symposium report believed such invigorators help control vortex bubble forms near upper surface leading edge can I: er section lift coefficients before stall practice fliers finding little benefit still-air times considerable improve ment stability stall recovery leading better performance rough conditions Most competitors chose use thin Bolso pylon Two plywood cross braces support rod Securing bolt through drilled rod Metal plate topped hole alunriniun strip pulled tight bolt Thin woll aluminium wotOr tube Wing pylon mounting system alumi num motortube used Eric Hanason Swe den holds securely givIng options rotate tell tilt move fore aft altering center-of-gravity trim setup Stabaliser chines extra stability 2 piece plugin wings aspect ratio121 carbon fibre spars IE Poam soft balsa fairing Carbon fibre motor tuba SECTION THROUGH FRONT CHINE graphic arts tape recommended Mar tin typically 006 thick 030 wide positioned 5% turbulator 4050 60 70 80% invigorators used primarily Dutch F lA FiB teams notably Anselmo Zen placed second Paul Sahi used 3mm nylon monofilament spanwise over ribs before covering Fl Glider achieve same effect Solid wings Like Lothars winning Es pada Britains Ivan Taylor also used solid balsa wings high aspect ratio Thin Liz Ivan narrowly missed top placing finishing 11th model proved could easily cope rough weather despite its apparent extreme layout Im sure apprehensive about constructing solid balsa wings especially undercamber Ivan explains its done wings difficult build need good light wood Planks cut shown illustration glued together very little wood need removed underside get shape use fairly coarse wet-and-dry sandpaper glued shaped sanding block finish finer grades Lightweight fiberglass cloth er sq yard used May1985 65 CEM Wakefield JP Van Leuven may wave futun Chines fitted wing tall improve airflow Increase lift according Pauls tests didnt fly chines-equipped model WC though Drawings courtesy Aero Modeller mag Left Clever positive prop-stop device Australian John Lewis whole prop hub assembly pushed back spring motor torque drops fixed pin engages pivoting notched arm nose block activate auto-rudder smaller spring pin left used hold wound motor before launching Right Chinese timer-cam-operated variable-incidence wing raises trailing edge whole wing during initial climb progressively dropping increase incidence until wing mount fully faired front wire pivot An adjusting screw rocks rear wire alter relative Incidence left right wing panels center panels Tulkote twopart polyurethane varnish ad hesive Ivan certainly appeared have no prob lems models getting wet unlike traditional tissue-covered models Furthermore inevitable damage brok en wings etc quickly repaired cyanoacrylate glue giving Ivan distinct advantage over others models re mained damaged unflyable New rubber Once again pop ular rubber Wakefield flying Pirelli has gone out productionfor good time rumored Japanese team managed turn up apparently good new supply manufactured Japan Dunlop used golf balls What types rubber might other Dunlop plants around world come up now Ed Dolbys FAI Model Supply PO Box 3957 Torrance CA 90510 rubber has gained popularity over years quality has improved would appear favorite choice future 1983 team member George Prop hub assembly used Ivan Taylor GB Thin Liz turned dural has two bail races silver-steel shaft torque stop via Russian-style setting pin located L-siot has 2mm piano wire outriggersanda plug-on spinner Schroedter Champion Model Products 880 Carmen Ct LaVerne CA 91750 now also marketing contest-grade rubber Georges brand similar FAI Model Supplys manufactured few thousandths inch thinner George believes will give fliers choice making up motors suit needs Wake-Up Incidentally George Schroed ter also made quite impression getting US team competing Aus tralia design also kits Champion Wake-Up has best serious Wakefield competition kit available modelers thanks considerable time care George spends preparing kit youre interested trying F 1 B could lot worse starting kits no problem achieving 4-min still-air maxes Taft during Team Finals Gadgets Generally speaking ap peared increasing trend people use timer-operated VIT control initial power burst up about 4 sec allows models trimmed more-forward CG allows greater wing incidence remaining climb glide may advantage particu larly stability rough windy weather Chinese models equipped 60 7-sec VIT movement tail lifted various shaped cams giving quick slow movement series steps Hans Zachalmels variation power fliers wing-twist mechanism al lowed left wing panel washed-out during climb returning flat wing less drag glide Positive prop stop problem facing Wakefield fliers transition end power run glide real issue concerns warps rudder used control climb need auto-rudder controlling glide actuate prop folds Using timer reliable itself actual length prop run will vary motor another best method would seem auto-rudder tripped action universally-adopted Montreal stop pin positively locates position blades instant folding problem spring-activat ed pin tends creep motor torque holds place during run finally falls off progressive creeping movement pin tends allow knock auto-rudder device several times can trip rudder prematurely results extra turn model still under power can cause model tighten-up lose altitudeobviously smooth transition anticipated Australian John Lewis solved prob lem quite neatly development idea Paul Lagan Johns hub uses notched pivoting arm activate autorudder Once arm begins tripped starts pivot thereby further blocking path rotating pin until securely held notch final resting place Montreal pin Byfilingthe arm first point contact lowest movement presents pin increasing obstruction guaranteeing firsttime stop Wakefield shuttle Paul Van Leuven placed second 1979 Taft time flying home ground Australia less fortunate dropping first last Continued page 159 First lamnate balsa planks cut angle 2to pro&sce undercamber 4 Next sand undersurface Wet dry sandpaper a sandsng block Fsnally shape top surface plane sandpaper Ivan Taylor solid balsa wing uses minimum amount balsa conse quently little removed final shaping 66 Model Aviation filed Secure back prop hub Also try support prop shaft two points eliminate wobble Power usually specified 10 strands Y-in brown rubber Brown rubber long gone same motor mod ern stock good place start often substitute six strands three loops A-in rubber good results Rubber motors twin pushers rigged no slack Some slack needed free-wheeling system work stretch first winding will usually provide motor should fit no droop between cans Motors wound opposite direc tions course easily determined checking prop rotation Early-day mod elers often modified egg beaters wind both motors simultaneously evenly can wound separately single winder need helper sure wind both motors equally Before flight check flying surfaces alignment warps incidence Inci dence usually 10 negative wing 3 positive elevator stabilizer Hand-glide model motors props adjust glide shifting wing forward correct diving elevator aft correct stalling fast flat glide desired first flight should low power 200-300 turns launch hold model wound props hub just give gentle push away low positive angle attack releasing props model should climb spiral Either direction fine should trimmed its natural turn direction increase turn washin elevator side away desired turn direction well gradually crease power successive flights usual ly quit about 600 750 turns 6 strands A-in rubber Glides relatively fast due drag stalling glide evident experiment basic incidences given above model refuses turn probably has too much dihedral An old rule thumb inch dihedral per foot wing span one-and-a-third inches per foot elevator span per side Competitions twin pushers widespread However informal competi tions available wherever two such models meet Todays competitions duration events time speed distance events held type can trimmed straightaway flight thus speed distance measur able comparable Today annual Society Antique Models SAM Championships include event twin-pushers one-flight duration contest often flown mass launch Last down wins although can sometimes difficult determine unless individual timers assigned model practice using panel visual judges sometimes ineffective due various flight patterns flown Welcome world twins Clarence Haught 3226 Honeysuckle Dr Coeur dAlene ID 83814 Fl B Tech/Cowley Continued page 66 rounds maxing through really wet windy ones Like fellow Aussies exhibits truly individualistic style models approach FAI flying Pauls latest concept wing chines streamlining device reduce fuselage tur bulence over flying surfaceswhich look like piggybacking space shuttle model Paul explains Wool tufts glued model showed airflow over wing near fuselage very unstableand established wing over fuselage produces less lift applying chines airflow much improved model behaves better glide Pauls ideas presented tech nical symposium during WC says found wing chines should have no 10 negative relation wing incidence claims further bonus under FAI rules wing area calculated extending line WILLIAMS ACCESSORIES BROTHER S 4 PILOTS ANDARD TSMAN RACING TARY WHEELS AGE TH CONTOUR BALLOON EN 4 ENGINES PRATT & WHITNEY HT HONE PARTS T & WHITNEY HONE GNOME AI5VICKERS DAU RELLUM FOR FULLY ILLUSTRATED CATALOG 4LLILIS SAN MARCOS CALIFORNIA 92069 ting advertisers mention read about Model Aviation 643-7616 • SHARP May1985 159 leading trailing edges does include area chines As turned out Paul did fly GEMChineEquipped Modelat WC plans develop idea Reports full Goulburn FE Sympos ium Report 29-page document including new wind-tunnel tests Stuttgart Martin Simons Power Model Trim Stan Hines Lost Wax Engine Casting Dave Sugden available New South Wales FF Society have left FE Champs Planbook 162 pages competitors biographical technical philosophical details together threeview plans also excellent purchase $1000 plus postage NSW FF So ciety Committe 50 Brown St St Peters NSW 2044 Australia responding advertisers mention read about Model Aviation CL Aerobatics/Fancher Continued page 67 dynamic components vehicle hope will fly manner desired B Preflight Phasewhat Large James Greenaway termed bench-trimming love letter published Stunt News wherein assembled airplane configured design parameters ie balance etc C Flying Phase wherein empirically evaluate suc cess earlier two phases make appropriate adjustments necessary D Post-Flight Phase wherein evalu ate subjective objective evidence planes performance Throughout four trim phases attempt optimize six major trim objec tives Stabilitydoes go its pointed constant attention does exit corners hard flat II Response ratedoes turn readily controllably III Line Tensionwhat causes good/bad line tension what about IV Speed Control too fast too slow adjust V Trackingdoes fly consecutive maneuvers concentrically does wander fix VI Turn equalitydoes turn equally both inside outside four phases trim six trim objectives plotted accompany ing table Beside objective variety design parameters inflight factors have effect partic ular objective listed approxi mately descending order influence phase trim parameter con sidered marked X exam ple Stability objective leadout location element Phases B C whereas sealing flap hinge line strictly flying trim consideration C Note addition table brok en down happy airplane side happy pilot side very important realize stated earlier columns handles handle interface between airplane pilot means whereby make properlytrimmed aircraft compatible differ ent pilots often difficult make distinction should kept constantly mind handle should nt adjusted camouflage what aircraft deficiency except last resort discussion will concentrate happy-airplane side comments happy pilot absolutely necessary Next month will start Phase Design Trim address parameters six Trim Objectives Subsequent columns will same succeeding phase few final comments order what assumptions have made plus few definitions terms First no attempt will made quan tify parameter will discussing concepts principles general specific terms ie lift-to-drag ratio improves higher aspect ratios L/D seven-to-one AR 137267% five-to-one AR etc will however provide some personal rules thumb hard numbers time S Send $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLIN FOX GOLD3ERG GUILLOWS JETCO K&3 PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS 1111 YALLET RUDDY CIIIfl 137 1 liii St Landau Fm 11146 leO ModelAviation ACCURATE ABLE TOREAD ACC U TAC H NOW IN TWO MODELS 3 FUNCTION4 FUNCTION ACCUSTACH 1ACCU-TACH 2 Digital8995 LCD tachometerSame useful capabilities has dual scale lOX-bOXas ACCU-TACH 1 stable RPM readoutincludes DC ammeter Full scale voltmeter canused check servo curbe used check/cyclerent Will find worn bindmost TXIRX battery com-ing stalled servo condi bos Reads loadtions w/SCA1 up 20 voltsAdd function ATi ACCESSORIESor SCAl -Servo Current Adaptor OSAl- Quarter Scale Adaptor ATi & AT2-500ma . 95 Airtronics Futaba Kraft 995 Send check MO NorCal AVIONICS IncINC P0 Box 70956 Sunnyvale CA 94086 Cahf add 6% tax Add $2 S&H See dealer first Old time Quality stiit I-LYLINfr Kit VOl9p. 5E9ISMM MPM 3-CbMORIl 0/C yd. PLACE AT TAR ENTER NATEERIALE$2195 FREE FLIANIT SCALE COSREETETIEN RICA AKit #103 MOORE WILE FROM TENS KIT TAlE MATAL VOWER nd 5O Phone 703 273-9593Flyline Models Catalog FLYLINE MODELS INC PO S. 2t3 Ffrf. Vh 121 USA EnI Parts Ofily have parts vntoty prompt dRIllveryi Over 23i itsmi Send *2W Out Current List
Edition: Model Aviation - 1985/05
Page Numbers: 64, 65, 66, 159, 160
Fi Technicalities DOUBLE CHAMPION highly-com petitive sport model flying FF World Championships level makes con secutive winners rare breed Since Wakefield Cup initiated 1928 two individuals have honor Americas Joe Ehrhardt won cup 1930 1931 Finlands Arne Ellila FiB World Champion 1949 1950 Only FlA Glider started 1946 another consecutive winner Rudi Lindner Germany 1954 1955 No has managed feat FiC Power remarkable Ger manys Lothar Doring should join select group 1983 FF World Cham pionships Goulburn Australia Lothars performance truly outstanding reasons nations competing WCs early days field competitors considerably tougher rules have refined over years limit performance models technologically challeng ing ever Add adverse weather conditions experienced both Spain 1981 andinAustraliain 1983 youll realize Lothars performance indeed exceptional Lothar attended Goulburn Champs defending champion al lowed pole full time round himself Compared three team mem bers other poles may sound like advantage However con sider fact Lothar work alone preparing models spotting thermals retrieving can imagine no sequential order author takes another look 1983 FiB Wakefield Rub ber World Cham pionships emphasis unique ideas models saw EMartyn Cowley small task As conditions turned out very windy lots rain Lothar faced major task defending title Probably no could have better suited such challenge Flying skills aside Lothar individualist com petition style involves thorough advance preparation models equipment al lowing him single-mindedly concentrate two twin thermister wind record ing machines unit placed 50 yards upwind other comparative unit pole years win makes three times row such equipment used World Champion Itzhak Ben-Itzhak flew similar device win Taft CA 1979 December 1983 ClAM meeting tabled proposal ban such equipment future events wonder Lothar would have voted Such change would certainly alter emphasis fly Wake field modelwhich unarguably develop ing highly-sophisticated meteorolog ical event thought subject future FF Championships As top places closely fought often seconds separate gold silver bronze medalists wouldnt good idea future invite three back next WC defend titlesand keep individual winner company lonely pole Lothars models already well publi cized Espada 80/1 design selec ted National Free Flight Society Ten Models Year 1982 Anselmo Zen scramble re maining places Goulburn produced exciting finish half-dozen fliers contention right up last flight Con sistent maxing Hollands Anselmo Zen after second-round 247 proved re wards keeping ones head after early mistake Anselmo describes conditions kind weather found F 1 B contest unlike used northern Europe dont mean easyjust frightening confident mental approach vital success Cer tainly others psychologically frightened high wind conse quent damage could expected 64 Model Aviation Left nvlgorators small turbulators toward rear upper wing surface helped rough weather conditions including Anseimo Zen placed second Middle Hans Zachalmels wing wigglerdevice holds left wing trailing edge high give washout forthe initial six seconds power burst climb Right Wing tipletts used control tip vortices Wewy Zhang PR China placed fifth Rolled balsa boom 19% Stabaliser adjustable DTAuto Rudder hook below Mylar streamer pops out D T compartment recovery aid corn fields reinforced carbon fibre Carbon fibre motor tube 12 strand motor 20% stretch D T timer recess button centre motor C G plastic cover actsTimer start/stop Wing chines for extra lift Montreal stop R mechanism fully enclosed front end610 x 830 outrigger prop models compete effec tively WC level need prepared mentally able concentrate winning under adverse conditions model flew opening rounds uses Benedek B63566 airfoil thickened upper surface relatively few warps An auto-rudder comes 3 sec VIT 1 sec later Anselmos models also feature electric retrieval buzzer unusual Wakefield unit weighs 9 gin runs 15 hours best model damaged upon land ing very windy fourth round chose use older reliable model last flights As usual didnt look scoreboard towards end knew max planned take no risks sol changed wound motors 15 minutes waiting final flight Peter DeBoer assisting prevented launching until certain As rain started again put third motor waited Most fliers finished stood alone line No streamers left nor much time last minutes liberation came form good thermal told news after 3-mi flight scoreboard proclaimed second place New ideas teams experiment ing invigorators WC series turbulators positioned towards rear upper surface wingin addition conventional turbulator near leading edge subject intro duced modelers Martin Pressnell 1982 NFFS Symposium report believed such invigorators help control vortex bubble forms near upper surface leading edge can I: er section lift coefficients before stall practice fliers finding little benefit still-air times considerable improve ment stability stall recovery leading better performance rough conditions Most competitors chose use thin Bolso pylon Two plywood cross braces support rod Securing bolt through drilled rod Metal plate topped hole alunriniun strip pulled tight bolt Thin woll aluminium wotOr tube Wing pylon mounting system alumi num motortube used Eric Hanason Swe den holds securely givIng options rotate tell tilt move fore aft altering center-of-gravity trim setup Stabaliser chines extra stability 2 piece plugin wings aspect ratio121 carbon fibre spars IE Poam soft balsa fairing Carbon fibre motor tuba SECTION THROUGH FRONT CHINE graphic arts tape recommended Mar tin typically 006 thick 030 wide positioned 5% turbulator 4050 60 70 80% invigorators used primarily Dutch F lA FiB teams notably Anselmo Zen placed second Paul Sahi used 3mm nylon monofilament spanwise over ribs before covering Fl Glider achieve same effect Solid wings Like Lothars winning Es pada Britains Ivan Taylor also used solid balsa wings high aspect ratio Thin Liz Ivan narrowly missed top placing finishing 11th model proved could easily cope rough weather despite its apparent extreme layout Im sure apprehensive about constructing solid balsa wings especially undercamber Ivan explains its done wings difficult build need good light wood Planks cut shown illustration glued together very little wood need removed underside get shape use fairly coarse wet-and-dry sandpaper glued shaped sanding block finish finer grades Lightweight fiberglass cloth er sq yard used May1985 65 CEM Wakefield JP Van Leuven may wave futun Chines fitted wing tall improve airflow Increase lift according Pauls tests didnt fly chines-equipped model WC though Drawings courtesy Aero Modeller mag Left Clever positive prop-stop device Australian John Lewis whole prop hub assembly pushed back spring motor torque drops fixed pin engages pivoting notched arm nose block activate auto-rudder smaller spring pin left used hold wound motor before launching Right Chinese timer-cam-operated variable-incidence wing raises trailing edge whole wing during initial climb progressively dropping increase incidence until wing mount fully faired front wire pivot An adjusting screw rocks rear wire alter relative Incidence left right wing panels center panels Tulkote twopart polyurethane varnish ad hesive Ivan certainly appeared have no prob lems models getting wet unlike traditional tissue-covered models Furthermore inevitable damage brok en wings etc quickly repaired cyanoacrylate glue giving Ivan distinct advantage over others models re mained damaged unflyable New rubber Once again pop ular rubber Wakefield flying Pirelli has gone out productionfor good time rumored Japanese team managed turn up apparently good new supply manufactured Japan Dunlop used golf balls What types rubber might other Dunlop plants around world come up now Ed Dolbys FAI Model Supply PO Box 3957 Torrance CA 90510 rubber has gained popularity over years quality has improved would appear favorite choice future 1983 team member George Prop hub assembly used Ivan Taylor GB Thin Liz turned dural has two bail races silver-steel shaft torque stop via Russian-style setting pin located L-siot has 2mm piano wire outriggersanda plug-on spinner Schroedter Champion Model Products 880 Carmen Ct LaVerne CA 91750 now also marketing contest-grade rubber Georges brand similar FAI Model Supplys manufactured few thousandths inch thinner George believes will give fliers choice making up motors suit needs Wake-Up Incidentally George Schroed ter also made quite impression getting US team competing Aus tralia design also kits Champion Wake-Up has best serious Wakefield competition kit available modelers thanks considerable time care George spends preparing kit youre interested trying F 1 B could lot worse starting kits no problem achieving 4-min still-air maxes Taft during Team Finals Gadgets Generally speaking ap peared increasing trend people use timer-operated VIT control initial power burst up about 4 sec allows models trimmed more-forward CG allows greater wing incidence remaining climb glide may advantage particu larly stability rough windy weather Chinese models equipped 60 7-sec VIT movement tail lifted various shaped cams giving quick slow movement series steps Hans Zachalmels variation power fliers wing-twist mechanism al lowed left wing panel washed-out during climb returning flat wing less drag glide Positive prop stop problem facing Wakefield fliers transition end power run glide real issue concerns warps rudder used control climb need auto-rudder controlling glide actuate prop folds Using timer reliable itself actual length prop run will vary motor another best method would seem auto-rudder tripped action universally-adopted Montreal stop pin positively locates position blades instant folding problem spring-activat ed pin tends creep motor torque holds place during run finally falls off progressive creeping movement pin tends allow knock auto-rudder device several times can trip rudder prematurely results extra turn model still under power can cause model tighten-up lose altitudeobviously smooth transition anticipated Australian John Lewis solved prob lem quite neatly development idea Paul Lagan Johns hub uses notched pivoting arm activate autorudder Once arm begins tripped starts pivot thereby further blocking path rotating pin until securely held notch final resting place Montreal pin Byfilingthe arm first point contact lowest movement presents pin increasing obstruction guaranteeing firsttime stop Wakefield shuttle Paul Van Leuven placed second 1979 Taft time flying home ground Australia less fortunate dropping first last Continued page 159 First lamnate balsa planks cut angle 2to pro&sce undercamber 4 Next sand undersurface Wet dry sandpaper a sandsng block Fsnally shape top surface plane sandpaper Ivan Taylor solid balsa wing uses minimum amount balsa conse quently little removed final shaping 66 Model Aviation filed Secure back prop hub Also try support prop shaft two points eliminate wobble Power usually specified 10 strands Y-in brown rubber Brown rubber long gone same motor mod ern stock good place start often substitute six strands three loops A-in rubber good results Rubber motors twin pushers rigged no slack Some slack needed free-wheeling system work stretch first winding will usually provide motor should fit no droop between cans Motors wound opposite direc tions course easily determined checking prop rotation Early-day mod elers often modified egg beaters wind both motors simultaneously evenly can wound separately single winder need helper sure wind both motors equally Before flight check flying surfaces alignment warps incidence Inci dence usually 10 negative wing 3 positive elevator stabilizer Hand-glide model motors props adjust glide shifting wing forward correct diving elevator aft correct stalling fast flat glide desired first flight should low power 200-300 turns launch hold model wound props hub just give gentle push away low positive angle attack releasing props model should climb spiral Either direction fine should trimmed its natural turn direction increase turn washin elevator side away desired turn direction well gradually crease power successive flights usual ly quit about 600 750 turns 6 strands A-in rubber Glides relatively fast due drag stalling glide evident experiment basic incidences given above model refuses turn probably has too much dihedral An old rule thumb inch dihedral per foot wing span one-and-a-third inches per foot elevator span per side Competitions twin pushers widespread However informal competi tions available wherever two such models meet Todays competitions duration events time speed distance events held type can trimmed straightaway flight thus speed distance measur able comparable Today annual Society Antique Models SAM Championships include event twin-pushers one-flight duration contest often flown mass launch Last down wins although can sometimes difficult determine unless individual timers assigned model practice using panel visual judges sometimes ineffective due various flight patterns flown Welcome world twins Clarence Haught 3226 Honeysuckle Dr Coeur dAlene ID 83814 Fl B Tech/Cowley Continued page 66 rounds maxing through really wet windy ones Like fellow Aussies exhibits truly individualistic style models approach FAI flying Pauls latest concept wing chines streamlining device reduce fuselage tur bulence over flying surfaceswhich look like piggybacking space shuttle model Paul explains Wool tufts glued model showed airflow over wing near fuselage very unstableand established wing over fuselage produces less lift applying chines airflow much improved model behaves better glide Pauls ideas presented tech nical symposium during WC says found wing chines should have no 10 negative relation wing incidence claims further bonus under FAI rules wing area calculated extending line WILLIAMS ACCESSORIES BROTHER S 4 PILOTS ANDARD TSMAN RACING TARY WHEELS AGE TH CONTOUR BALLOON EN 4 ENGINES PRATT & WHITNEY HT HONE PARTS T & WHITNEY HONE GNOME AI5VICKERS DAU RELLUM FOR FULLY ILLUSTRATED CATALOG 4LLILIS SAN MARCOS CALIFORNIA 92069 ting advertisers mention read about Model Aviation 643-7616 • SHARP May1985 159 leading trailing edges does include area chines As turned out Paul did fly GEMChineEquipped Modelat WC plans develop idea Reports full Goulburn FE Sympos ium Report 29-page document including new wind-tunnel tests Stuttgart Martin Simons Power Model Trim Stan Hines Lost Wax Engine Casting Dave Sugden available New South Wales FF Society have left FE Champs Planbook 162 pages competitors biographical technical philosophical details together threeview plans also excellent purchase $1000 plus postage NSW FF So ciety Committe 50 Brown St St Peters NSW 2044 Australia responding advertisers mention read about Model Aviation CL Aerobatics/Fancher Continued page 67 dynamic components vehicle hope will fly manner desired B Preflight Phasewhat Large James Greenaway termed bench-trimming love letter published Stunt News wherein assembled airplane configured design parameters ie balance etc C Flying Phase wherein empirically evaluate suc cess earlier two phases make appropriate adjustments necessary D Post-Flight Phase wherein evalu ate subjective objective evidence planes performance Throughout four trim phases attempt optimize six major trim objec tives Stabilitydoes go its pointed constant attention does exit corners hard flat II Response ratedoes turn readily controllably III Line Tensionwhat causes good/bad line tension what about IV Speed Control too fast too slow adjust V Trackingdoes fly consecutive maneuvers concentrically does wander fix VI Turn equalitydoes turn equally both inside outside four phases trim six trim objectives plotted accompany ing table Beside objective variety design parameters inflight factors have effect partic ular objective listed approxi mately descending order influence phase trim parameter con sidered marked X exam ple Stability objective leadout location element Phases B C whereas sealing flap hinge line strictly flying trim consideration C Note addition table brok en down happy airplane side happy pilot side very important realize stated earlier columns handles handle interface between airplane pilot means whereby make properlytrimmed aircraft compatible differ ent pilots often difficult make distinction should kept constantly mind handle should nt adjusted camouflage what aircraft deficiency except last resort discussion will concentrate happy-airplane side comments happy pilot absolutely necessary Next month will start Phase Design Trim address parameters six Trim Objectives Subsequent columns will same succeeding phase few final comments order what assumptions have made plus few definitions terms First no attempt will made quan tify parameter will discussing concepts principles general specific terms ie lift-to-drag ratio improves higher aspect ratios L/D seven-to-one AR 137267% five-to-one AR etc will however provide some personal rules thumb hard numbers time S Send $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLIN FOX GOLD3ERG GUILLOWS JETCO K&3 PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS 1111 YALLET RUDDY CIIIfl 137 1 liii St Landau Fm 11146 leO ModelAviation ACCURATE ABLE TOREAD ACC U TAC H NOW IN TWO MODELS 3 FUNCTION4 FUNCTION ACCUSTACH 1ACCU-TACH 2 Digital8995 LCD tachometerSame useful capabilities has dual scale lOX-bOXas ACCU-TACH 1 stable RPM readoutincludes DC ammeter Full scale voltmeter canused check servo curbe used check/cyclerent Will find worn bindmost TXIRX battery com-ing stalled servo condi bos Reads loadtions w/SCA1 up 20 voltsAdd function ATi ACCESSORIESor SCAl -Servo Current Adaptor OSAl- Quarter Scale Adaptor ATi & AT2-500ma . 95 Airtronics Futaba Kraft 995 Send check MO NorCal AVIONICS IncINC P0 Box 70956 Sunnyvale CA 94086 Cahf add 6% tax Add $2 S&H See dealer first Old time Quality stiit I-LYLINfr Kit VOl9p. 5E9ISMM MPM 3-CbMORIl 0/C yd. PLACE AT TAR ENTER NATEERIALE$2195 FREE FLIANIT SCALE COSREETETIEN RICA AKit #103 MOORE WILE FROM TENS KIT TAlE MATAL VOWER nd 5O Phone 703 273-9593Flyline Models Catalog FLYLINE MODELS INC PO S. 2t3 Ffrf. Vh 121 USA EnI Parts Ofily have parts vntoty prompt dRIllveryi Over 23i itsmi Send *2W Out Current List
Edition: Model Aviation - 1985/05
Page Numbers: 64, 65, 66, 159, 160
Fi Technicalities DOUBLE CHAMPION highly-com petitive sport model flying FF World Championships level makes con secutive winners rare breed Since Wakefield Cup initiated 1928 two individuals have honor Americas Joe Ehrhardt won cup 1930 1931 Finlands Arne Ellila FiB World Champion 1949 1950 Only FlA Glider started 1946 another consecutive winner Rudi Lindner Germany 1954 1955 No has managed feat FiC Power remarkable Ger manys Lothar Doring should join select group 1983 FF World Cham pionships Goulburn Australia Lothars performance truly outstanding reasons nations competing WCs early days field competitors considerably tougher rules have refined over years limit performance models technologically challeng ing ever Add adverse weather conditions experienced both Spain 1981 andinAustraliain 1983 youll realize Lothars performance indeed exceptional Lothar attended Goulburn Champs defending champion al lowed pole full time round himself Compared three team mem bers other poles may sound like advantage However con sider fact Lothar work alone preparing models spotting thermals retrieving can imagine no sequential order author takes another look 1983 FiB Wakefield Rub ber World Cham pionships emphasis unique ideas models saw EMartyn Cowley small task As conditions turned out very windy lots rain Lothar faced major task defending title Probably no could have better suited such challenge Flying skills aside Lothar individualist com petition style involves thorough advance preparation models equipment al lowing him single-mindedly concentrate two twin thermister wind record ing machines unit placed 50 yards upwind other comparative unit pole years win makes three times row such equipment used World Champion Itzhak Ben-Itzhak flew similar device win Taft CA 1979 December 1983 ClAM meeting tabled proposal ban such equipment future events wonder Lothar would have voted Such change would certainly alter emphasis fly Wake field modelwhich unarguably develop ing highly-sophisticated meteorolog ical event thought subject future FF Championships As top places closely fought often seconds separate gold silver bronze medalists wouldnt good idea future invite three back next WC defend titlesand keep individual winner company lonely pole Lothars models already well publi cized Espada 80/1 design selec ted National Free Flight Society Ten Models Year 1982 Anselmo Zen scramble re maining places Goulburn produced exciting finish half-dozen fliers contention right up last flight Con sistent maxing Hollands Anselmo Zen after second-round 247 proved re wards keeping ones head after early mistake Anselmo describes conditions kind weather found F 1 B contest unlike used northern Europe dont mean easyjust frightening confident mental approach vital success Cer tainly others psychologically frightened high wind conse quent damage could expected 64 Model Aviation Left nvlgorators small turbulators toward rear upper wing surface helped rough weather conditions including Anseimo Zen placed second Middle Hans Zachalmels wing wigglerdevice holds left wing trailing edge high give washout forthe initial six seconds power burst climb Right Wing tipletts used control tip vortices Wewy Zhang PR China placed fifth Rolled balsa boom 19% Stabaliser adjustable DTAuto Rudder hook below Mylar streamer pops out D T compartment recovery aid corn fields reinforced carbon fibre Carbon fibre motor tube 12 strand motor 20% stretch D T timer recess button centre motor C G plastic cover actsTimer start/stop Wing chines for extra lift Montreal stop R mechanism fully enclosed front end610 x 830 outrigger prop models compete effec tively WC level need prepared mentally able concentrate winning under adverse conditions model flew opening rounds uses Benedek B63566 airfoil thickened upper surface relatively few warps An auto-rudder comes 3 sec VIT 1 sec later Anselmos models also feature electric retrieval buzzer unusual Wakefield unit weighs 9 gin runs 15 hours best model damaged upon land ing very windy fourth round chose use older reliable model last flights As usual didnt look scoreboard towards end knew max planned take no risks sol changed wound motors 15 minutes waiting final flight Peter DeBoer assisting prevented launching until certain As rain started again put third motor waited Most fliers finished stood alone line No streamers left nor much time last minutes liberation came form good thermal told news after 3-mi flight scoreboard proclaimed second place New ideas teams experiment ing invigorators WC series turbulators positioned towards rear upper surface wingin addition conventional turbulator near leading edge subject intro duced modelers Martin Pressnell 1982 NFFS Symposium report believed such invigorators help control vortex bubble forms near upper surface leading edge can I: er section lift coefficients before stall practice fliers finding little benefit still-air times considerable improve ment stability stall recovery leading better performance rough conditions Most competitors chose use thin Bolso pylon Two plywood cross braces support rod Securing bolt through drilled rod Metal plate topped hole alunriniun strip pulled tight bolt Thin woll aluminium wotOr tube Wing pylon mounting system alumi num motortube used Eric Hanason Swe den holds securely givIng options rotate tell tilt move fore aft altering center-of-gravity trim setup Stabaliser chines extra stability 2 piece plugin wings aspect ratio121 carbon fibre spars IE Poam soft balsa fairing Carbon fibre motor tuba SECTION THROUGH FRONT CHINE graphic arts tape recommended Mar tin typically 006 thick 030 wide positioned 5% turbulator 4050 60 70 80% invigorators used primarily Dutch F lA FiB teams notably Anselmo Zen placed second Paul Sahi used 3mm nylon monofilament spanwise over ribs before covering Fl Glider achieve same effect Solid wings Like Lothars winning Es pada Britains Ivan Taylor also used solid balsa wings high aspect ratio Thin Liz Ivan narrowly missed top placing finishing 11th model proved could easily cope rough weather despite its apparent extreme layout Im sure apprehensive about constructing solid balsa wings especially undercamber Ivan explains its done wings difficult build need good light wood Planks cut shown illustration glued together very little wood need removed underside get shape use fairly coarse wet-and-dry sandpaper glued shaped sanding block finish finer grades Lightweight fiberglass cloth er sq yard used May1985 65 CEM Wakefield JP Van Leuven may wave futun Chines fitted wing tall improve airflow Increase lift according Pauls tests didnt fly chines-equipped model WC though Drawings courtesy Aero Modeller mag Left Clever positive prop-stop device Australian John Lewis whole prop hub assembly pushed back spring motor torque drops fixed pin engages pivoting notched arm nose block activate auto-rudder smaller spring pin left used hold wound motor before launching Right Chinese timer-cam-operated variable-incidence wing raises trailing edge whole wing during initial climb progressively dropping increase incidence until wing mount fully faired front wire pivot An adjusting screw rocks rear wire alter relative Incidence left right wing panels center panels Tulkote twopart polyurethane varnish ad hesive Ivan certainly appeared have no prob lems models getting wet unlike traditional tissue-covered models Furthermore inevitable damage brok en wings etc quickly repaired cyanoacrylate glue giving Ivan distinct advantage over others models re mained damaged unflyable New rubber Once again pop ular rubber Wakefield flying Pirelli has gone out productionfor good time rumored Japanese team managed turn up apparently good new supply manufactured Japan Dunlop used golf balls What types rubber might other Dunlop plants around world come up now Ed Dolbys FAI Model Supply PO Box 3957 Torrance CA 90510 rubber has gained popularity over years quality has improved would appear favorite choice future 1983 team member George Prop hub assembly used Ivan Taylor GB Thin Liz turned dural has two bail races silver-steel shaft torque stop via Russian-style setting pin located L-siot has 2mm piano wire outriggersanda plug-on spinner Schroedter Champion Model Products 880 Carmen Ct LaVerne CA 91750 now also marketing contest-grade rubber Georges brand similar FAI Model Supplys manufactured few thousandths inch thinner George believes will give fliers choice making up motors suit needs Wake-Up Incidentally George Schroed ter also made quite impression getting US team competing Aus tralia design also kits Champion Wake-Up has best serious Wakefield competition kit available modelers thanks considerable time care George spends preparing kit youre interested trying F 1 B could lot worse starting kits no problem achieving 4-min still-air maxes Taft during Team Finals Gadgets Generally speaking ap peared increasing trend people use timer-operated VIT control initial power burst up about 4 sec allows models trimmed more-forward CG allows greater wing incidence remaining climb glide may advantage particu larly stability rough windy weather Chinese models equipped 60 7-sec VIT movement tail lifted various shaped cams giving quick slow movement series steps Hans Zachalmels variation power fliers wing-twist mechanism al lowed left wing panel washed-out during climb returning flat wing less drag glide Positive prop stop problem facing Wakefield fliers transition end power run glide real issue concerns warps rudder used control climb need auto-rudder controlling glide actuate prop folds Using timer reliable itself actual length prop run will vary motor another best method would seem auto-rudder tripped action universally-adopted Montreal stop pin positively locates position blades instant folding problem spring-activat ed pin tends creep motor torque holds place during run finally falls off progressive creeping movement pin tends allow knock auto-rudder device several times can trip rudder prematurely results extra turn model still under power can cause model tighten-up lose altitudeobviously smooth transition anticipated Australian John Lewis solved prob lem quite neatly development idea Paul Lagan Johns hub uses notched pivoting arm activate autorudder Once arm begins tripped starts pivot thereby further blocking path rotating pin until securely held notch final resting place Montreal pin Byfilingthe arm first point contact lowest movement presents pin increasing obstruction guaranteeing firsttime stop Wakefield shuttle Paul Van Leuven placed second 1979 Taft time flying home ground Australia less fortunate dropping first last Continued page 159 First lamnate balsa planks cut angle 2to pro&sce undercamber 4 Next sand undersurface Wet dry sandpaper a sandsng block Fsnally shape top surface plane sandpaper Ivan Taylor solid balsa wing uses minimum amount balsa conse quently little removed final shaping 66 Model Aviation filed Secure back prop hub Also try support prop shaft two points eliminate wobble Power usually specified 10 strands Y-in brown rubber Brown rubber long gone same motor mod ern stock good place start often substitute six strands three loops A-in rubber good results Rubber motors twin pushers rigged no slack Some slack needed free-wheeling system work stretch first winding will usually provide motor should fit no droop between cans Motors wound opposite direc tions course easily determined checking prop rotation Early-day mod elers often modified egg beaters wind both motors simultaneously evenly can wound separately single winder need helper sure wind both motors equally Before flight check flying surfaces alignment warps incidence Inci dence usually 10 negative wing 3 positive elevator stabilizer Hand-glide model motors props adjust glide shifting wing forward correct diving elevator aft correct stalling fast flat glide desired first flight should low power 200-300 turns launch hold model wound props hub just give gentle push away low positive angle attack releasing props model should climb spiral Either direction fine should trimmed its natural turn direction increase turn washin elevator side away desired turn direction well gradually crease power successive flights usual ly quit about 600 750 turns 6 strands A-in rubber Glides relatively fast due drag stalling glide evident experiment basic incidences given above model refuses turn probably has too much dihedral An old rule thumb inch dihedral per foot wing span one-and-a-third inches per foot elevator span per side Competitions twin pushers widespread However informal competi tions available wherever two such models meet Todays competitions duration events time speed distance events held type can trimmed straightaway flight thus speed distance measur able comparable Today annual Society Antique Models SAM Championships include event twin-pushers one-flight duration contest often flown mass launch Last down wins although can sometimes difficult determine unless individual timers assigned model practice using panel visual judges sometimes ineffective due various flight patterns flown Welcome world twins Clarence Haught 3226 Honeysuckle Dr Coeur dAlene ID 83814 Fl B Tech/Cowley Continued page 66 rounds maxing through really wet windy ones Like fellow Aussies exhibits truly individualistic style models approach FAI flying Pauls latest concept wing chines streamlining device reduce fuselage tur bulence over flying surfaceswhich look like piggybacking space shuttle model Paul explains Wool tufts glued model showed airflow over wing near fuselage very unstableand established wing over fuselage produces less lift applying chines airflow much improved model behaves better glide Pauls ideas presented tech nical symposium during WC says found wing chines should have no 10 negative relation wing incidence claims further bonus under FAI rules wing area calculated extending line WILLIAMS ACCESSORIES BROTHER S 4 PILOTS ANDARD TSMAN RACING TARY WHEELS AGE TH CONTOUR BALLOON EN 4 ENGINES PRATT & WHITNEY HT HONE PARTS T & WHITNEY HONE GNOME AI5VICKERS DAU RELLUM FOR FULLY ILLUSTRATED CATALOG 4LLILIS SAN MARCOS CALIFORNIA 92069 ting advertisers mention read about Model Aviation 643-7616 • SHARP May1985 159 leading trailing edges does include area chines As turned out Paul did fly GEMChineEquipped Modelat WC plans develop idea Reports full Goulburn FE Sympos ium Report 29-page document including new wind-tunnel tests Stuttgart Martin Simons Power Model Trim Stan Hines Lost Wax Engine Casting Dave Sugden available New South Wales FF Society have left FE Champs Planbook 162 pages competitors biographical technical philosophical details together threeview plans also excellent purchase $1000 plus postage NSW FF So ciety Committe 50 Brown St St Peters NSW 2044 Australia responding advertisers mention read about Model Aviation CL Aerobatics/Fancher Continued page 67 dynamic components vehicle hope will fly manner desired B Preflight Phasewhat Large James Greenaway termed bench-trimming love letter published Stunt News wherein assembled airplane configured design parameters ie balance etc C Flying Phase wherein empirically evaluate suc cess earlier two phases make appropriate adjustments necessary D Post-Flight Phase wherein evalu ate subjective objective evidence planes performance Throughout four trim phases attempt optimize six major trim objec tives Stabilitydoes go its pointed constant attention does exit corners hard flat II Response ratedoes turn readily controllably III Line Tensionwhat causes good/bad line tension what about IV Speed Control too fast too slow adjust V Trackingdoes fly consecutive maneuvers concentrically does wander fix VI Turn equalitydoes turn equally both inside outside four phases trim six trim objectives plotted accompany ing table Beside objective variety design parameters inflight factors have effect partic ular objective listed approxi mately descending order influence phase trim parameter con sidered marked X exam ple Stability objective leadout location element Phases B C whereas sealing flap hinge line strictly flying trim consideration C Note addition table brok en down happy airplane side happy pilot side very important realize stated earlier columns handles handle interface between airplane pilot means whereby make properlytrimmed aircraft compatible differ ent pilots often difficult make distinction should kept constantly mind handle should nt adjusted camouflage what aircraft deficiency except last resort discussion will concentrate happy-airplane side comments happy pilot absolutely necessary Next month will start Phase Design Trim address parameters six Trim Objectives Subsequent columns will same succeeding phase few final comments order what assumptions have made plus few definitions terms First no attempt will made quan tify parameter will discussing concepts principles general specific terms ie lift-to-drag ratio improves higher aspect ratios L/D seven-to-one AR 137267% five-to-one AR etc will however provide some personal rules thumb hard numbers time S Send $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLIN FOX GOLD3ERG GUILLOWS JETCO K&3 PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS 1111 YALLET RUDDY CIIIfl 137 1 liii St Landau Fm 11146 leO ModelAviation ACCURATE ABLE TOREAD ACC U TAC H NOW IN TWO MODELS 3 FUNCTION4 FUNCTION ACCUSTACH 1ACCU-TACH 2 Digital8995 LCD tachometerSame useful capabilities has dual scale lOX-bOXas ACCU-TACH 1 stable RPM readoutincludes DC ammeter Full scale voltmeter canused check servo curbe used check/cyclerent Will find worn bindmost TXIRX battery com-ing stalled servo condi bos Reads loadtions w/SCA1 up 20 voltsAdd function ATi ACCESSORIESor SCAl -Servo Current Adaptor OSAl- Quarter Scale Adaptor ATi & AT2-500ma . 95 Airtronics Futaba Kraft 995 Send check MO NorCal AVIONICS IncINC P0 Box 70956 Sunnyvale CA 94086 Cahf add 6% tax Add $2 S&H See dealer first Old time Quality stiit I-LYLINfr Kit VOl9p. 5E9ISMM MPM 3-CbMORIl 0/C yd. PLACE AT TAR ENTER NATEERIALE$2195 FREE FLIANIT SCALE COSREETETIEN RICA AKit #103 MOORE WILE FROM TENS KIT TAlE MATAL VOWER nd 5O Phone 703 273-9593Flyline Models Catalog FLYLINE MODELS INC PO S. 2t3 Ffrf. Vh 121 USA EnI Parts Ofily have parts vntoty prompt dRIllveryi Over 23i itsmi Send *2W Out Current List
Edition: Model Aviation - 1985/05
Page Numbers: 64, 65, 66, 159, 160
Fi Technicalities DOUBLE CHAMPION highly-com petitive sport model flying FF World Championships level makes con secutive winners rare breed Since Wakefield Cup initiated 1928 two individuals have honor Americas Joe Ehrhardt won cup 1930 1931 Finlands Arne Ellila FiB World Champion 1949 1950 Only FlA Glider started 1946 another consecutive winner Rudi Lindner Germany 1954 1955 No has managed feat FiC Power remarkable Ger manys Lothar Doring should join select group 1983 FF World Cham pionships Goulburn Australia Lothars performance truly outstanding reasons nations competing WCs early days field competitors considerably tougher rules have refined over years limit performance models technologically challeng ing ever Add adverse weather conditions experienced both Spain 1981 andinAustraliain 1983 youll realize Lothars performance indeed exceptional Lothar attended Goulburn Champs defending champion al lowed pole full time round himself Compared three team mem bers other poles may sound like advantage However con sider fact Lothar work alone preparing models spotting thermals retrieving can imagine no sequential order author takes another look 1983 FiB Wakefield Rub ber World Cham pionships emphasis unique ideas models saw EMartyn Cowley small task As conditions turned out very windy lots rain Lothar faced major task defending title Probably no could have better suited such challenge Flying skills aside Lothar individualist com petition style involves thorough advance preparation models equipment al lowing him single-mindedly concentrate two twin thermister wind record ing machines unit placed 50 yards upwind other comparative unit pole years win makes three times row such equipment used World Champion Itzhak Ben-Itzhak flew similar device win Taft CA 1979 December 1983 ClAM meeting tabled proposal ban such equipment future events wonder Lothar would have voted Such change would certainly alter emphasis fly Wake field modelwhich unarguably develop ing highly-sophisticated meteorolog ical event thought subject future FF Championships As top places closely fought often seconds separate gold silver bronze medalists wouldnt good idea future invite three back next WC defend titlesand keep individual winner company lonely pole Lothars models already well publi cized Espada 80/1 design selec ted National Free Flight Society Ten Models Year 1982 Anselmo Zen scramble re maining places Goulburn produced exciting finish half-dozen fliers contention right up last flight Con sistent maxing Hollands Anselmo Zen after second-round 247 proved re wards keeping ones head after early mistake Anselmo describes conditions kind weather found F 1 B contest unlike used northern Europe dont mean easyjust frightening confident mental approach vital success Cer tainly others psychologically frightened high wind conse quent damage could expected 64 Model Aviation Left nvlgorators small turbulators toward rear upper wing surface helped rough weather conditions including Anseimo Zen placed second Middle Hans Zachalmels wing wigglerdevice holds left wing trailing edge high give washout forthe initial six seconds power burst climb Right Wing tipletts used control tip vortices Wewy Zhang PR China placed fifth Rolled balsa boom 19% Stabaliser adjustable DTAuto Rudder hook below Mylar streamer pops out D T compartment recovery aid corn fields reinforced carbon fibre Carbon fibre motor tube 12 strand motor 20% stretch D T timer recess button centre motor C G plastic cover actsTimer start/stop Wing chines for extra lift Montreal stop R mechanism fully enclosed front end610 x 830 outrigger prop models compete effec tively WC level need prepared mentally able concentrate winning under adverse conditions model flew opening rounds uses Benedek B63566 airfoil thickened upper surface relatively few warps An auto-rudder comes 3 sec VIT 1 sec later Anselmos models also feature electric retrieval buzzer unusual Wakefield unit weighs 9 gin runs 15 hours best model damaged upon land ing very windy fourth round chose use older reliable model last flights As usual didnt look scoreboard towards end knew max planned take no risks sol changed wound motors 15 minutes waiting final flight Peter DeBoer assisting prevented launching until certain As rain started again put third motor waited Most fliers finished stood alone line No streamers left nor much time last minutes liberation came form good thermal told news after 3-mi flight scoreboard proclaimed second place New ideas teams experiment ing invigorators WC series turbulators positioned towards rear upper surface wingin addition conventional turbulator near leading edge subject intro duced modelers Martin Pressnell 1982 NFFS Symposium report believed such invigorators help control vortex bubble forms near upper surface leading edge can I: er section lift coefficients before stall practice fliers finding little benefit still-air times considerable improve ment stability stall recovery leading better performance rough conditions Most competitors chose use thin Bolso pylon Two plywood cross braces support rod Securing bolt through drilled rod Metal plate topped hole alunriniun strip pulled tight bolt Thin woll aluminium wotOr tube Wing pylon mounting system alumi num motortube used Eric Hanason Swe den holds securely givIng options rotate tell tilt move fore aft altering center-of-gravity trim setup Stabaliser chines extra stability 2 piece plugin wings aspect ratio121 carbon fibre spars IE Poam soft balsa fairing Carbon fibre motor tuba SECTION THROUGH FRONT CHINE graphic arts tape recommended Mar tin typically 006 thick 030 wide positioned 5% turbulator 4050 60 70 80% invigorators used primarily Dutch F lA FiB teams notably Anselmo Zen placed second Paul Sahi used 3mm nylon monofilament spanwise over ribs before covering Fl Glider achieve same effect Solid wings Like Lothars winning Es pada Britains Ivan Taylor also used solid balsa wings high aspect ratio Thin Liz Ivan narrowly missed top placing finishing 11th model proved could easily cope rough weather despite its apparent extreme layout Im sure apprehensive about constructing solid balsa wings especially undercamber Ivan explains its done wings difficult build need good light wood Planks cut shown illustration glued together very little wood need removed underside get shape use fairly coarse wet-and-dry sandpaper glued shaped sanding block finish finer grades Lightweight fiberglass cloth er sq yard used May1985 65 CEM Wakefield JP Van Leuven may wave futun Chines fitted wing tall improve airflow Increase lift according Pauls tests didnt fly chines-equipped model WC though Drawings courtesy Aero Modeller mag Left Clever positive prop-stop device Australian John Lewis whole prop hub assembly pushed back spring motor torque drops fixed pin engages pivoting notched arm nose block activate auto-rudder smaller spring pin left used hold wound motor before launching Right Chinese timer-cam-operated variable-incidence wing raises trailing edge whole wing during initial climb progressively dropping increase incidence until wing mount fully faired front wire pivot An adjusting screw rocks rear wire alter relative Incidence left right wing panels center panels Tulkote twopart polyurethane varnish ad hesive Ivan certainly appeared have no prob lems models getting wet unlike traditional tissue-covered models Furthermore inevitable damage brok en wings etc quickly repaired cyanoacrylate glue giving Ivan distinct advantage over others models re mained damaged unflyable New rubber Once again pop ular rubber Wakefield flying Pirelli has gone out productionfor good time rumored Japanese team managed turn up apparently good new supply manufactured Japan Dunlop used golf balls What types rubber might other Dunlop plants around world come up now Ed Dolbys FAI Model Supply PO Box 3957 Torrance CA 90510 rubber has gained popularity over years quality has improved would appear favorite choice future 1983 team member George Prop hub assembly used Ivan Taylor GB Thin Liz turned dural has two bail races silver-steel shaft torque stop via Russian-style setting pin located L-siot has 2mm piano wire outriggersanda plug-on spinner Schroedter Champion Model Products 880 Carmen Ct LaVerne CA 91750 now also marketing contest-grade rubber Georges brand similar FAI Model Supplys manufactured few thousandths inch thinner George believes will give fliers choice making up motors suit needs Wake-Up Incidentally George Schroed ter also made quite impression getting US team competing Aus tralia design also kits Champion Wake-Up has best serious Wakefield competition kit available modelers thanks considerable time care George spends preparing kit youre interested trying F 1 B could lot worse starting kits no problem achieving 4-min still-air maxes Taft during Team Finals Gadgets Generally speaking ap peared increasing trend people use timer-operated VIT control initial power burst up about 4 sec allows models trimmed more-forward CG allows greater wing incidence remaining climb glide may advantage particu larly stability rough windy weather Chinese models equipped 60 7-sec VIT movement tail lifted various shaped cams giving quick slow movement series steps Hans Zachalmels variation power fliers wing-twist mechanism al lowed left wing panel washed-out during climb returning flat wing less drag glide Positive prop stop problem facing Wakefield fliers transition end power run glide real issue concerns warps rudder used control climb need auto-rudder controlling glide actuate prop folds Using timer reliable itself actual length prop run will vary motor another best method would seem auto-rudder tripped action universally-adopted Montreal stop pin positively locates position blades instant folding problem spring-activat ed pin tends creep motor torque holds place during run finally falls off progressive creeping movement pin tends allow knock auto-rudder device several times can trip rudder prematurely results extra turn model still under power can cause model tighten-up lose altitudeobviously smooth transition anticipated Australian John Lewis solved prob lem quite neatly development idea Paul Lagan Johns hub uses notched pivoting arm activate autorudder Once arm begins tripped starts pivot thereby further blocking path rotating pin until securely held notch final resting place Montreal pin Byfilingthe arm first point contact lowest movement presents pin increasing obstruction guaranteeing firsttime stop Wakefield shuttle Paul Van Leuven placed second 1979 Taft time flying home ground Australia less fortunate dropping first last Continued page 159 First lamnate balsa planks cut angle 2to pro&sce undercamber 4 Next sand undersurface Wet dry sandpaper a sandsng block Fsnally shape top surface plane sandpaper Ivan Taylor solid balsa wing uses minimum amount balsa conse quently little removed final shaping 66 Model Aviation filed Secure back prop hub Also try support prop shaft two points eliminate wobble Power usually specified 10 strands Y-in brown rubber Brown rubber long gone same motor mod ern stock good place start often substitute six strands three loops A-in rubber good results Rubber motors twin pushers rigged no slack Some slack needed free-wheeling system work stretch first winding will usually provide motor should fit no droop between cans Motors wound opposite direc tions course easily determined checking prop rotation Early-day mod elers often modified egg beaters wind both motors simultaneously evenly can wound separately single winder need helper sure wind both motors equally Before flight check flying surfaces alignment warps incidence Inci dence usually 10 negative wing 3 positive elevator stabilizer Hand-glide model motors props adjust glide shifting wing forward correct diving elevator aft correct stalling fast flat glide desired first flight should low power 200-300 turns launch hold model wound props hub just give gentle push away low positive angle attack releasing props model should climb spiral Either direction fine should trimmed its natural turn direction increase turn washin elevator side away desired turn direction well gradually crease power successive flights usual ly quit about 600 750 turns 6 strands A-in rubber Glides relatively fast due drag stalling glide evident experiment basic incidences given above model refuses turn probably has too much dihedral An old rule thumb inch dihedral per foot wing span one-and-a-third inches per foot elevator span per side Competitions twin pushers widespread However informal competi tions available wherever two such models meet Todays competitions duration events time speed distance events held type can trimmed straightaway flight thus speed distance measur able comparable Today annual Society Antique Models SAM Championships include event twin-pushers one-flight duration contest often flown mass launch Last down wins although can sometimes difficult determine unless individual timers assigned model practice using panel visual judges sometimes ineffective due various flight patterns flown Welcome world twins Clarence Haught 3226 Honeysuckle Dr Coeur dAlene ID 83814 Fl B Tech/Cowley Continued page 66 rounds maxing through really wet windy ones Like fellow Aussies exhibits truly individualistic style models approach FAI flying Pauls latest concept wing chines streamlining device reduce fuselage tur bulence over flying surfaceswhich look like piggybacking space shuttle model Paul explains Wool tufts glued model showed airflow over wing near fuselage very unstableand established wing over fuselage produces less lift applying chines airflow much improved model behaves better glide Pauls ideas presented tech nical symposium during WC says found wing chines should have no 10 negative relation wing incidence claims further bonus under FAI rules wing area calculated extending line WILLIAMS ACCESSORIES BROTHER S 4 PILOTS ANDARD TSMAN RACING TARY WHEELS AGE TH CONTOUR BALLOON EN 4 ENGINES PRATT & WHITNEY HT HONE PARTS T & WHITNEY HONE GNOME AI5VICKERS DAU RELLUM FOR FULLY ILLUSTRATED CATALOG 4LLILIS SAN MARCOS CALIFORNIA 92069 ting advertisers mention read about Model Aviation 643-7616 • SHARP May1985 159 leading trailing edges does include area chines As turned out Paul did fly GEMChineEquipped Modelat WC plans develop idea Reports full Goulburn FE Sympos ium Report 29-page document including new wind-tunnel tests Stuttgart Martin Simons Power Model Trim Stan Hines Lost Wax Engine Casting Dave Sugden available New South Wales FF Society have left FE Champs Planbook 162 pages competitors biographical technical philosophical details together threeview plans also excellent purchase $1000 plus postage NSW FF So ciety Committe 50 Brown St St Peters NSW 2044 Australia responding advertisers mention read about Model Aviation CL Aerobatics/Fancher Continued page 67 dynamic components vehicle hope will fly manner desired B Preflight Phasewhat Large James Greenaway termed bench-trimming love letter published Stunt News wherein assembled airplane configured design parameters ie balance etc C Flying Phase wherein empirically evaluate suc cess earlier two phases make appropriate adjustments necessary D Post-Flight Phase wherein evalu ate subjective objective evidence planes performance Throughout four trim phases attempt optimize six major trim objec tives Stabilitydoes go its pointed constant attention does exit corners hard flat II Response ratedoes turn readily controllably III Line Tensionwhat causes good/bad line tension what about IV Speed Control too fast too slow adjust V Trackingdoes fly consecutive maneuvers concentrically does wander fix VI Turn equalitydoes turn equally both inside outside four phases trim six trim objectives plotted accompany ing table Beside objective variety design parameters inflight factors have effect partic ular objective listed approxi mately descending order influence phase trim parameter con sidered marked X exam ple Stability objective leadout location element Phases B C whereas sealing flap hinge line strictly flying trim consideration C Note addition table brok en down happy airplane side happy pilot side very important realize stated earlier columns handles handle interface between airplane pilot means whereby make properlytrimmed aircraft compatible differ ent pilots often difficult make distinction should kept constantly mind handle should nt adjusted camouflage what aircraft deficiency except last resort discussion will concentrate happy-airplane side comments happy pilot absolutely necessary Next month will start Phase Design Trim address parameters six Trim Objectives Subsequent columns will same succeeding phase few final comments order what assumptions have made plus few definitions terms First no attempt will made quan tify parameter will discussing concepts principles general specific terms ie lift-to-drag ratio improves higher aspect ratios L/D seven-to-one AR 137267% five-to-one AR etc will however provide some personal rules thumb hard numbers time S Send $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLIN FOX GOLD3ERG GUILLOWS JETCO K&3 PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS 1111 YALLET RUDDY CIIIfl 137 1 liii St Landau Fm 11146 leO ModelAviation ACCURATE ABLE TOREAD ACC U TAC H NOW IN TWO MODELS 3 FUNCTION4 FUNCTION ACCUSTACH 1ACCU-TACH 2 Digital8995 LCD tachometerSame useful capabilities has dual scale lOX-bOXas ACCU-TACH 1 stable RPM readoutincludes DC ammeter Full scale voltmeter canused check servo curbe used check/cyclerent Will find worn bindmost TXIRX battery com-ing stalled servo condi bos Reads loadtions w/SCA1 up 20 voltsAdd function ATi ACCESSORIESor SCAl -Servo Current Adaptor OSAl- Quarter Scale Adaptor ATi & AT2-500ma . 95 Airtronics Futaba Kraft 995 Send check MO NorCal AVIONICS IncINC P0 Box 70956 Sunnyvale CA 94086 Cahf add 6% tax Add $2 S&H See dealer first Old time Quality stiit I-LYLINfr Kit VOl9p. 5E9ISMM MPM 3-CbMORIl 0/C yd. PLACE AT TAR ENTER NATEERIALE$2195 FREE FLIANIT SCALE COSREETETIEN RICA AKit #103 MOORE WILE FROM TENS KIT TAlE MATAL VOWER nd 5O Phone 703 273-9593Flyline Models Catalog FLYLINE MODELS INC PO S. 2t3 Ffrf. Vh 121 USA EnI Parts Ofily have parts vntoty prompt dRIllveryi Over 23i itsmi Send *2W Out Current List
Edition: Model Aviation - 1985/05
Page Numbers: 64, 65, 66, 159, 160
Fi Technicalities DOUBLE CHAMPION highly-com petitive sport model flying FF World Championships level makes con secutive winners rare breed Since Wakefield Cup initiated 1928 two individuals have honor Americas Joe Ehrhardt won cup 1930 1931 Finlands Arne Ellila FiB World Champion 1949 1950 Only FlA Glider started 1946 another consecutive winner Rudi Lindner Germany 1954 1955 No has managed feat FiC Power remarkable Ger manys Lothar Doring should join select group 1983 FF World Cham pionships Goulburn Australia Lothars performance truly outstanding reasons nations competing WCs early days field competitors considerably tougher rules have refined over years limit performance models technologically challeng ing ever Add adverse weather conditions experienced both Spain 1981 andinAustraliain 1983 youll realize Lothars performance indeed exceptional Lothar attended Goulburn Champs defending champion al lowed pole full time round himself Compared three team mem bers other poles may sound like advantage However con sider fact Lothar work alone preparing models spotting thermals retrieving can imagine no sequential order author takes another look 1983 FiB Wakefield Rub ber World Cham pionships emphasis unique ideas models saw EMartyn Cowley small task As conditions turned out very windy lots rain Lothar faced major task defending title Probably no could have better suited such challenge Flying skills aside Lothar individualist com petition style involves thorough advance preparation models equipment al lowing him single-mindedly concentrate two twin thermister wind record ing machines unit placed 50 yards upwind other comparative unit pole years win makes three times row such equipment used World Champion Itzhak Ben-Itzhak flew similar device win Taft CA 1979 December 1983 ClAM meeting tabled proposal ban such equipment future events wonder Lothar would have voted Such change would certainly alter emphasis fly Wake field modelwhich unarguably develop ing highly-sophisticated meteorolog ical event thought subject future FF Championships As top places closely fought often seconds separate gold silver bronze medalists wouldnt good idea future invite three back next WC defend titlesand keep individual winner company lonely pole Lothars models already well publi cized Espada 80/1 design selec ted National Free Flight Society Ten Models Year 1982 Anselmo Zen scramble re maining places Goulburn produced exciting finish half-dozen fliers contention right up last flight Con sistent maxing Hollands Anselmo Zen after second-round 247 proved re wards keeping ones head after early mistake Anselmo describes conditions kind weather found F 1 B contest unlike used northern Europe dont mean easyjust frightening confident mental approach vital success Cer tainly others psychologically frightened high wind conse quent damage could expected 64 Model Aviation Left nvlgorators small turbulators toward rear upper wing surface helped rough weather conditions including Anseimo Zen placed second Middle Hans Zachalmels wing wigglerdevice holds left wing trailing edge high give washout forthe initial six seconds power burst climb Right Wing tipletts used control tip vortices Wewy Zhang PR China placed fifth Rolled balsa boom 19% Stabaliser adjustable DTAuto Rudder hook below Mylar streamer pops out D T compartment recovery aid corn fields reinforced carbon fibre Carbon fibre motor tube 12 strand motor 20% stretch D T timer recess button centre motor C G plastic cover actsTimer start/stop Wing chines for extra lift Montreal stop R mechanism fully enclosed front end610 x 830 outrigger prop models compete effec tively WC level need prepared mentally able concentrate winning under adverse conditions model flew opening rounds uses Benedek B63566 airfoil thickened upper surface relatively few warps An auto-rudder comes 3 sec VIT 1 sec later Anselmos models also feature electric retrieval buzzer unusual Wakefield unit weighs 9 gin runs 15 hours best model damaged upon land ing very windy fourth round chose use older reliable model last flights As usual didnt look scoreboard towards end knew max planned take no risks sol changed wound motors 15 minutes waiting final flight Peter DeBoer assisting prevented launching until certain As rain started again put third motor waited Most fliers finished stood alone line No streamers left nor much time last minutes liberation came form good thermal told news after 3-mi flight scoreboard proclaimed second place New ideas teams experiment ing invigorators WC series turbulators positioned towards rear upper surface wingin addition conventional turbulator near leading edge subject intro duced modelers Martin Pressnell 1982 NFFS Symposium report believed such invigorators help control vortex bubble forms near upper surface leading edge can I: er section lift coefficients before stall practice fliers finding little benefit still-air times considerable improve ment stability stall recovery leading better performance rough conditions Most competitors chose use thin Bolso pylon Two plywood cross braces support rod Securing bolt through drilled rod Metal plate topped hole alunriniun strip pulled tight bolt Thin woll aluminium wotOr tube Wing pylon mounting system alumi num motortube used Eric Hanason Swe den holds securely givIng options rotate tell tilt move fore aft altering center-of-gravity trim setup Stabaliser chines extra stability 2 piece plugin wings aspect ratio121 carbon fibre spars IE Poam soft balsa fairing Carbon fibre motor tuba SECTION THROUGH FRONT CHINE graphic arts tape recommended Mar tin typically 006 thick 030 wide positioned 5% turbulator 4050 60 70 80% invigorators used primarily Dutch F lA FiB teams notably Anselmo Zen placed second Paul Sahi used 3mm nylon monofilament spanwise over ribs before covering Fl Glider achieve same effect Solid wings Like Lothars winning Es pada Britains Ivan Taylor also used solid balsa wings high aspect ratio Thin Liz Ivan narrowly missed top placing finishing 11th model proved could easily cope rough weather despite its apparent extreme layout Im sure apprehensive about constructing solid balsa wings especially undercamber Ivan explains its done wings difficult build need good light wood Planks cut shown illustration glued together very little wood need removed underside get shape use fairly coarse wet-and-dry sandpaper glued shaped sanding block finish finer grades Lightweight fiberglass cloth er sq yard used May1985 65 CEM Wakefield JP Van Leuven may wave futun Chines fitted wing tall improve airflow Increase lift according Pauls tests didnt fly chines-equipped model WC though Drawings courtesy Aero Modeller mag Left Clever positive prop-stop device Australian John Lewis whole prop hub assembly pushed back spring motor torque drops fixed pin engages pivoting notched arm nose block activate auto-rudder smaller spring pin left used hold wound motor before launching Right Chinese timer-cam-operated variable-incidence wing raises trailing edge whole wing during initial climb progressively dropping increase incidence until wing mount fully faired front wire pivot An adjusting screw rocks rear wire alter relative Incidence left right wing panels center panels Tulkote twopart polyurethane varnish ad hesive Ivan certainly appeared have no prob lems models getting wet unlike traditional tissue-covered models Furthermore inevitable damage brok en wings etc quickly repaired cyanoacrylate glue giving Ivan distinct advantage over others models re mained damaged unflyable New rubber Once again pop ular rubber Wakefield flying Pirelli has gone out productionfor good time rumored Japanese team managed turn up apparently good new supply manufactured Japan Dunlop used golf balls What types rubber might other Dunlop plants around world come up now Ed Dolbys FAI Model Supply PO Box 3957 Torrance CA 90510 rubber has gained popularity over years quality has improved would appear favorite choice future 1983 team member George Prop hub assembly used Ivan Taylor GB Thin Liz turned dural has two bail races silver-steel shaft torque stop via Russian-style setting pin located L-siot has 2mm piano wire outriggersanda plug-on spinner Schroedter Champion Model Products 880 Carmen Ct LaVerne CA 91750 now also marketing contest-grade rubber Georges brand similar FAI Model Supplys manufactured few thousandths inch thinner George believes will give fliers choice making up motors suit needs Wake-Up Incidentally George Schroed ter also made quite impression getting US team competing Aus tralia design also kits Champion Wake-Up has best serious Wakefield competition kit available modelers thanks considerable time care George spends preparing kit youre interested trying F 1 B could lot worse starting kits no problem achieving 4-min still-air maxes Taft during Team Finals Gadgets Generally speaking ap peared increasing trend people use timer-operated VIT control initial power burst up about 4 sec allows models trimmed more-forward CG allows greater wing incidence remaining climb glide may advantage particu larly stability rough windy weather Chinese models equipped 60 7-sec VIT movement tail lifted various shaped cams giving quick slow movement series steps Hans Zachalmels variation power fliers wing-twist mechanism al lowed left wing panel washed-out during climb returning flat wing less drag glide Positive prop stop problem facing Wakefield fliers transition end power run glide real issue concerns warps rudder used control climb need auto-rudder controlling glide actuate prop folds Using timer reliable itself actual length prop run will vary motor another best method would seem auto-rudder tripped action universally-adopted Montreal stop pin positively locates position blades instant folding problem spring-activat ed pin tends creep motor torque holds place during run finally falls off progressive creeping movement pin tends allow knock auto-rudder device several times can trip rudder prematurely results extra turn model still under power can cause model tighten-up lose altitudeobviously smooth transition anticipated Australian John Lewis solved prob lem quite neatly development idea Paul Lagan Johns hub uses notched pivoting arm activate autorudder Once arm begins tripped starts pivot thereby further blocking path rotating pin until securely held notch final resting place Montreal pin Byfilingthe arm first point contact lowest movement presents pin increasing obstruction guaranteeing firsttime stop Wakefield shuttle Paul Van Leuven placed second 1979 Taft time flying home ground Australia less fortunate dropping first last Continued page 159 First lamnate balsa planks cut angle 2to pro&sce undercamber 4 Next sand undersurface Wet dry sandpaper a sandsng block Fsnally shape top surface plane sandpaper Ivan Taylor solid balsa wing uses minimum amount balsa conse quently little removed final shaping 66 Model Aviation filed Secure back prop hub Also try support prop shaft two points eliminate wobble Power usually specified 10 strands Y-in brown rubber Brown rubber long gone same motor mod ern stock good place start often substitute six strands three loops A-in rubber good results Rubber motors twin pushers rigged no slack Some slack needed free-wheeling system work stretch first winding will usually provide motor should fit no droop between cans Motors wound opposite direc tions course easily determined checking prop rotation Early-day mod elers often modified egg beaters wind both motors simultaneously evenly can wound separately single winder need helper sure wind both motors equally Before flight check flying surfaces alignment warps incidence Inci dence usually 10 negative wing 3 positive elevator stabilizer Hand-glide model motors props adjust glide shifting wing forward correct diving elevator aft correct stalling fast flat glide desired first flight should low power 200-300 turns launch hold model wound props hub just give gentle push away low positive angle attack releasing props model should climb spiral Either direction fine should trimmed its natural turn direction increase turn washin elevator side away desired turn direction well gradually crease power successive flights usual ly quit about 600 750 turns 6 strands A-in rubber Glides relatively fast due drag stalling glide evident experiment basic incidences given above model refuses turn probably has too much dihedral An old rule thumb inch dihedral per foot wing span one-and-a-third inches per foot elevator span per side Competitions twin pushers widespread However informal competi tions available wherever two such models meet Todays competitions duration events time speed distance events held type can trimmed straightaway flight thus speed distance measur able comparable Today annual Society Antique Models SAM Championships include event twin-pushers one-flight duration contest often flown mass launch Last down wins although can sometimes difficult determine unless individual timers assigned model practice using panel visual judges sometimes ineffective due various flight patterns flown Welcome world twins Clarence Haught 3226 Honeysuckle Dr Coeur dAlene ID 83814 Fl B Tech/Cowley Continued page 66 rounds maxing through really wet windy ones Like fellow Aussies exhibits truly individualistic style models approach FAI flying Pauls latest concept wing chines streamlining device reduce fuselage tur bulence over flying surfaceswhich look like piggybacking space shuttle model Paul explains Wool tufts glued model showed airflow over wing near fuselage very unstableand established wing over fuselage produces less lift applying chines airflow much improved model behaves better glide Pauls ideas presented tech nical symposium during WC says found wing chines should have no 10 negative relation wing incidence claims further bonus under FAI rules wing area calculated extending line WILLIAMS ACCESSORIES BROTHER S 4 PILOTS ANDARD TSMAN RACING TARY WHEELS AGE TH CONTOUR BALLOON EN 4 ENGINES PRATT & WHITNEY HT HONE PARTS T & WHITNEY HONE GNOME AI5VICKERS DAU RELLUM FOR FULLY ILLUSTRATED CATALOG 4LLILIS SAN MARCOS CALIFORNIA 92069 ting advertisers mention read about Model Aviation 643-7616 • SHARP May1985 159 leading trailing edges does include area chines As turned out Paul did fly GEMChineEquipped Modelat WC plans develop idea Reports full Goulburn FE Sympos ium Report 29-page document including new wind-tunnel tests Stuttgart Martin Simons Power Model Trim Stan Hines Lost Wax Engine Casting Dave Sugden available New South Wales FF Society have left FE Champs Planbook 162 pages competitors biographical technical philosophical details together threeview plans also excellent purchase $1000 plus postage NSW FF So ciety Committe 50 Brown St St Peters NSW 2044 Australia responding advertisers mention read about Model Aviation CL Aerobatics/Fancher Continued page 67 dynamic components vehicle hope will fly manner desired B Preflight Phasewhat Large James Greenaway termed bench-trimming love letter published Stunt News wherein assembled airplane configured design parameters ie balance etc C Flying Phase wherein empirically evaluate suc cess earlier two phases make appropriate adjustments necessary D Post-Flight Phase wherein evalu ate subjective objective evidence planes performance Throughout four trim phases attempt optimize six major trim objec tives Stabilitydoes go its pointed constant attention does exit corners hard flat II Response ratedoes turn readily controllably III Line Tensionwhat causes good/bad line tension what about IV Speed Control too fast too slow adjust V Trackingdoes fly consecutive maneuvers concentrically does wander fix VI Turn equalitydoes turn equally both inside outside four phases trim six trim objectives plotted accompany ing table Beside objective variety design parameters inflight factors have effect partic ular objective listed approxi mately descending order influence phase trim parameter con sidered marked X exam ple Stability objective leadout location element Phases B C whereas sealing flap hinge line strictly flying trim consideration C Note addition table brok en down happy airplane side happy pilot side very important realize stated earlier columns handles handle interface between airplane pilot means whereby make properlytrimmed aircraft compatible differ ent pilots often difficult make distinction should kept constantly mind handle should nt adjusted camouflage what aircraft deficiency except last resort discussion will concentrate happy-airplane side comments happy pilot absolutely necessary Next month will start Phase Design Trim address parameters six Trim Objectives Subsequent columns will same succeeding phase few final comments order what assumptions have made plus few definitions terms First no attempt will made quan tify parameter will discussing concepts principles general specific terms ie lift-to-drag ratio improves higher aspect ratios L/D seven-to-one AR 137267% five-to-one AR etc will however provide some personal rules thumb hard numbers time S Send $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLIN FOX GOLD3ERG GUILLOWS JETCO K&3 PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS 1111 YALLET RUDDY CIIIfl 137 1 liii St Landau Fm 11146 leO ModelAviation ACCURATE ABLE TOREAD ACC U TAC H NOW IN TWO MODELS 3 FUNCTION4 FUNCTION ACCUSTACH 1ACCU-TACH 2 Digital8995 LCD tachometerSame useful capabilities has dual scale lOX-bOXas ACCU-TACH 1 stable RPM readoutincludes DC ammeter Full scale voltmeter canused check servo curbe used check/cyclerent Will find worn bindmost TXIRX battery com-ing stalled servo condi bos Reads loadtions w/SCA1 up 20 voltsAdd function ATi ACCESSORIESor SCAl -Servo Current Adaptor OSAl- Quarter Scale Adaptor ATi & AT2-500ma . 95 Airtronics Futaba Kraft 995 Send check MO NorCal AVIONICS IncINC P0 Box 70956 Sunnyvale CA 94086 Cahf add 6% tax Add $2 S&H See dealer first Old time Quality stiit I-LYLINfr Kit VOl9p. 5E9ISMM MPM 3-CbMORIl 0/C yd. PLACE AT TAR ENTER NATEERIALE$2195 FREE FLIANIT SCALE COSREETETIEN RICA AKit #103 MOORE WILE FROM TENS KIT TAlE MATAL VOWER nd 5O Phone 703 273-9593Flyline Models Catalog FLYLINE MODELS INC PO S. 2t3 Ffrf. Vh 121 USA EnI Parts Ofily have parts vntoty prompt dRIllveryi Over 23i itsmi Send *2W Out Current List