Variable-Camber Wings Adding scale detail such variable-camber wings can easier youd think U Robert Fiorenze WHAT scale builder doesnt want duplicate feature fullsize prototype some cases thats difficult impractical goal other cases its easily achieved latest scale project Yellow Aircraft F- 18 Hornet competed successfully installation operable wing flap leading edge slat systems However competition since evolved point extra gadgetry became almost requirement problem change wings variable camber raised some interesting aerodynamic questions help turned friend aerospace engineer Mickey Nowell followed advice designing flap slat system Static testing results convinced system practical mainly concerned about what would happen leading edge slats during inverted flight model upright leading edge slats have nowhere go plane inverted slats have servo pushrod support See companion section Calculation C Forces Turn Resulting Wing Loading solve problem asked machinist friend Tony Sano modify set Rhom-Air pneumatic cylinders modified cylinder locks slats up position high-speed flying included locking pin protrndes right side fuselage receptacle slat pin tapered hence self-seating receptacle slightly out alignment pin will force receptacle proper alignment lock place Construction I laid out dimensions slats flaps stock wing made cutouts secure hinge mounting laminated layer Locking cylinder components shown bottom completed unit top Left right tapered receptor glued leading edge wing slat machined mounting bracket locking pin Rhom-Air cylinder plywood balsa See illustration 1 used Robart #309 Super Point Hinges exclusively Carbon fiber reinforcements used high-stress areas such point slat/flap servo pushrod connects slat hinging complete cut opening slat flap servo lined opening ply Note position servo horn illustration 2 photos horn located exactly shown flaps will pulled down slat being pushed down During flight forces acting flap help counter forces acting slatrather like tug-of-war chose Futaba 9302 servo flaps helicopter ball links connection points After positioning wing fuselage glued tapered locking pin receptors leading edge slats Calculation G Forces Turn Resulting Wing Loading THE notes illustration follow explain loads Yellow Aircraft F-18 Hornet estimated tested drawing 25-lb airplane 400-ft radius traveling 140 mph formula centripetal acceleration found physics book city2/radius Note following calculations rounded off needed rough numbers planned add gross safety factor anyway situation centripetal acceleration v2Ir 205 x 205/400 - 105 ft/sec2 normal G 322 ft/sec2 Thus airplane loaded 105/322 G Adding safety factor estimated loadof5G airplane weighs 25 lb plane loaded 5 G making turn wings carrying [5 x 25] lb 125 lb ignoring fuselage contribution wing panel carrying 625 lb leading edge slats carry some percentage loadsay 25% Multiplying approximately 60 lb 25% yields 15 lb force slat An additional safety factor 2 multiplied yield test load 30 lb equivalent loading 10G Since loading slat assumed uniform leading edge hinge line estimated conservatively slat would sustain 15-lb uniform load given turn Doubling load 30 lb equivalent flying 10-G turn turn radius 130 ft 140 mph Thats way outside performance airplane indicates magnitude test load involved load testing cardboard box matching slat outline filled 30 lb sand placed slat Though seems almost counterintuitive especially watching test slat sustained load Dispersed loads deceiving 4 December1992 11 R400feet $ 8/60 feet] secoed V 140 ,ph feet/cecond IKON NWST Since 1977 IKON offers largest selection giant scale kits world order kits call 1-800-327-7198 catalog fine kits send $4 00 dah Re de Add5 SaeSaesTa Futaba 9302- 4-40 Pushrods Flap Servo Robart #309 Super Point Futaba 9201 III9Hines Aileron Servo static testing made cardboard box same shape leading edge slat filled 30 pounds sand concentrated load slat system showed no signs fatigue confidence rose Tonys help devised substitute wind tunnel testing Tony made bracket hold modified Illustration 1 Slat-and-flap arrangement hingemounting pads laminated balsa ply Illustration 2 Servo horns counterclockwise rotation top pulls flap down pushes slat down wings outside car window Testing done fuselage hence aid locking pins though speed car never approached flight speed aircraft became apparent locking pins required design speed range however provide extra assurance against loading conditions place stress slat-and-flap system fully deployed servo horn positioned flap left being pulled down slat right pushed down See Illustration 1 slatand-f lap system retracted 12 Model Aviation on Fiber Reinforcement BalsaPly Slat \7/ Rap 6 RYAN PT-22 1/4 SCALE 90 STINSON SR-B 1/5 SCALE 100 PILATUS PORTER GIANT SCALE 98 P51D MIJSTANG HAND CRAFTED FREE-FLIGHT GLIDERS Best Looldag Best Flying Most DLrile Gliders Deed * READY TO FLY * Large 22 Wing Span Plug-In Reinforced Wing Unbreahabie Body Totally Adustable Tall Capale Loops Straight & Level Flight & 50 Drneter Boomerang Banks Return Thrower $1295 plus $200 S&H 15300 S&H 2 Day Delivery y Qers shipped sane day Checks must dear 30 Day Satlaleoflon Guarantee Phone/Fax 516424-mi Info RIKERAIRcRAFT70FcfwdsonAveEsatHampton NY11937 tapered slat-locking pin protrudes right side fuselage wing has yet mounted slatconditions impossible calculate before flying model Flight testing Given outstanding flight characteristics stock Yellow Aircraft F- 18 wing knew would take lot ruin planes performance Fortunately slat/flap system worked beautifully F-18s already good slow-speed characteristics actually improved no problems showed up high speeds confident going flight testing positive results made box placed test load concentrated slat safety factor used calculating load variable-camber wing system appears have worth extra building time minor modifications system should adaptable other aircraft decide include gadgets next project hope theyll work successfully VER 80 MANUFACTURERSSWAP SHOPHUNDREDS OF MODELSCONCESSIONS AIRCRAFTBOATSCARSRAILROADS INDOOR-OUTDOOR RIC CAR RACINGBOAT DEMONSTRATIONS IN OUTDOOR POOL CONTROL LINE DEMONSTRATIONSR/C HELICOPTER DEMONSTRATIONS ELECTRIC R/C PLANE DEMONSTRATIONS 9 AM-S PM SATURDAY 10 AM-S PM SUNDAY WESTERN WASHINGTON FAIRGROUNDS PUYALLUP WASHINGTON RADIO CONTROLLED MODELS December1992 13 stress-testing cardboard sandbox custom-made shape LE slat filled 30-lb load r slat-and-flap system sustained 30-lb load no signs fatigue bucket supported wing S JAN 3Oth-3lst r ADULTS $500 CHILDREN 6-12 $300 u/adult SENIOR CITIZENS $300
Edition: Model Aviation - 1992/12
Page Numbers: 11, 12, 13
Variable-Camber Wings Adding scale detail such variable-camber wings can easier youd think U Robert Fiorenze WHAT scale builder doesnt want duplicate feature fullsize prototype some cases thats difficult impractical goal other cases its easily achieved latest scale project Yellow Aircraft F- 18 Hornet competed successfully installation operable wing flap leading edge slat systems However competition since evolved point extra gadgetry became almost requirement problem change wings variable camber raised some interesting aerodynamic questions help turned friend aerospace engineer Mickey Nowell followed advice designing flap slat system Static testing results convinced system practical mainly concerned about what would happen leading edge slats during inverted flight model upright leading edge slats have nowhere go plane inverted slats have servo pushrod support See companion section Calculation C Forces Turn Resulting Wing Loading solve problem asked machinist friend Tony Sano modify set Rhom-Air pneumatic cylinders modified cylinder locks slats up position high-speed flying included locking pin protrndes right side fuselage receptacle slat pin tapered hence self-seating receptacle slightly out alignment pin will force receptacle proper alignment lock place Construction I laid out dimensions slats flaps stock wing made cutouts secure hinge mounting laminated layer Locking cylinder components shown bottom completed unit top Left right tapered receptor glued leading edge wing slat machined mounting bracket locking pin Rhom-Air cylinder plywood balsa See illustration 1 used Robart #309 Super Point Hinges exclusively Carbon fiber reinforcements used high-stress areas such point slat/flap servo pushrod connects slat hinging complete cut opening slat flap servo lined opening ply Note position servo horn illustration 2 photos horn located exactly shown flaps will pulled down slat being pushed down During flight forces acting flap help counter forces acting slatrather like tug-of-war chose Futaba 9302 servo flaps helicopter ball links connection points After positioning wing fuselage glued tapered locking pin receptors leading edge slats Calculation G Forces Turn Resulting Wing Loading THE notes illustration follow explain loads Yellow Aircraft F-18 Hornet estimated tested drawing 25-lb airplane 400-ft radius traveling 140 mph formula centripetal acceleration found physics book city2/radius Note following calculations rounded off needed rough numbers planned add gross safety factor anyway situation centripetal acceleration v2Ir 205 x 205/400 - 105 ft/sec2 normal G 322 ft/sec2 Thus airplane loaded 105/322 G Adding safety factor estimated loadof5G airplane weighs 25 lb plane loaded 5 G making turn wings carrying [5 x 25] lb 125 lb ignoring fuselage contribution wing panel carrying 625 lb leading edge slats carry some percentage loadsay 25% Multiplying approximately 60 lb 25% yields 15 lb force slat An additional safety factor 2 multiplied yield test load 30 lb equivalent loading 10G Since loading slat assumed uniform leading edge hinge line estimated conservatively slat would sustain 15-lb uniform load given turn Doubling load 30 lb equivalent flying 10-G turn turn radius 130 ft 140 mph Thats way outside performance airplane indicates magnitude test load involved load testing cardboard box matching slat outline filled 30 lb sand placed slat Though seems almost counterintuitive especially watching test slat sustained load Dispersed loads deceiving 4 December1992 11 R400feet $ 8/60 feet] secoed V 140 ,ph feet/cecond IKON NWST Since 1977 IKON offers largest selection giant scale kits world order kits call 1-800-327-7198 catalog fine kits send $4 00 dah Re de Add5 SaeSaesTa Futaba 9302- 4-40 Pushrods Flap Servo Robart #309 Super Point Futaba 9201 III9Hines Aileron Servo static testing made cardboard box same shape leading edge slat filled 30 pounds sand concentrated load slat system showed no signs fatigue confidence rose Tonys help devised substitute wind tunnel testing Tony made bracket hold modified Illustration 1 Slat-and-flap arrangement hingemounting pads laminated balsa ply Illustration 2 Servo horns counterclockwise rotation top pulls flap down pushes slat down wings outside car window Testing done fuselage hence aid locking pins though speed car never approached flight speed aircraft became apparent locking pins required design speed range however provide extra assurance against loading conditions place stress slat-and-flap system fully deployed servo horn positioned flap left being pulled down slat right pushed down See Illustration 1 slatand-f lap system retracted 12 Model Aviation on Fiber Reinforcement BalsaPly Slat \7/ Rap 6 RYAN PT-22 1/4 SCALE 90 STINSON SR-B 1/5 SCALE 100 PILATUS PORTER GIANT SCALE 98 P51D MIJSTANG HAND CRAFTED FREE-FLIGHT GLIDERS Best Looldag Best Flying Most DLrile Gliders Deed * READY TO FLY * Large 22 Wing Span Plug-In Reinforced Wing Unbreahabie Body Totally Adustable Tall Capale Loops Straight & Level Flight & 50 Drneter Boomerang Banks Return Thrower $1295 plus $200 S&H 15300 S&H 2 Day Delivery y Qers shipped sane day Checks must dear 30 Day Satlaleoflon Guarantee Phone/Fax 516424-mi Info RIKERAIRcRAFT70FcfwdsonAveEsatHampton NY11937 tapered slat-locking pin protrudes right side fuselage wing has yet mounted slatconditions impossible calculate before flying model Flight testing Given outstanding flight characteristics stock Yellow Aircraft F- 18 wing knew would take lot ruin planes performance Fortunately slat/flap system worked beautifully F-18s already good slow-speed characteristics actually improved no problems showed up high speeds confident going flight testing positive results made box placed test load concentrated slat safety factor used calculating load variable-camber wing system appears have worth extra building time minor modifications system should adaptable other aircraft decide include gadgets next project hope theyll work successfully VER 80 MANUFACTURERSSWAP SHOPHUNDREDS OF MODELSCONCESSIONS AIRCRAFTBOATSCARSRAILROADS INDOOR-OUTDOOR RIC CAR RACINGBOAT DEMONSTRATIONS IN OUTDOOR POOL CONTROL LINE DEMONSTRATIONSR/C HELICOPTER DEMONSTRATIONS ELECTRIC R/C PLANE DEMONSTRATIONS 9 AM-S PM SATURDAY 10 AM-S PM SUNDAY WESTERN WASHINGTON FAIRGROUNDS PUYALLUP WASHINGTON RADIO CONTROLLED MODELS December1992 13 stress-testing cardboard sandbox custom-made shape LE slat filled 30-lb load r slat-and-flap system sustained 30-lb load no signs fatigue bucket supported wing S JAN 3Oth-3lst r ADULTS $500 CHILDREN 6-12 $300 u/adult SENIOR CITIZENS $300
Edition: Model Aviation - 1992/12
Page Numbers: 11, 12, 13
Variable-Camber Wings Adding scale detail such variable-camber wings can easier youd think U Robert Fiorenze WHAT scale builder doesnt want duplicate feature fullsize prototype some cases thats difficult impractical goal other cases its easily achieved latest scale project Yellow Aircraft F- 18 Hornet competed successfully installation operable wing flap leading edge slat systems However competition since evolved point extra gadgetry became almost requirement problem change wings variable camber raised some interesting aerodynamic questions help turned friend aerospace engineer Mickey Nowell followed advice designing flap slat system Static testing results convinced system practical mainly concerned about what would happen leading edge slats during inverted flight model upright leading edge slats have nowhere go plane inverted slats have servo pushrod support See companion section Calculation C Forces Turn Resulting Wing Loading solve problem asked machinist friend Tony Sano modify set Rhom-Air pneumatic cylinders modified cylinder locks slats up position high-speed flying included locking pin protrndes right side fuselage receptacle slat pin tapered hence self-seating receptacle slightly out alignment pin will force receptacle proper alignment lock place Construction I laid out dimensions slats flaps stock wing made cutouts secure hinge mounting laminated layer Locking cylinder components shown bottom completed unit top Left right tapered receptor glued leading edge wing slat machined mounting bracket locking pin Rhom-Air cylinder plywood balsa See illustration 1 used Robart #309 Super Point Hinges exclusively Carbon fiber reinforcements used high-stress areas such point slat/flap servo pushrod connects slat hinging complete cut opening slat flap servo lined opening ply Note position servo horn illustration 2 photos horn located exactly shown flaps will pulled down slat being pushed down During flight forces acting flap help counter forces acting slatrather like tug-of-war chose Futaba 9302 servo flaps helicopter ball links connection points After positioning wing fuselage glued tapered locking pin receptors leading edge slats Calculation G Forces Turn Resulting Wing Loading THE notes illustration follow explain loads Yellow Aircraft F-18 Hornet estimated tested drawing 25-lb airplane 400-ft radius traveling 140 mph formula centripetal acceleration found physics book city2/radius Note following calculations rounded off needed rough numbers planned add gross safety factor anyway situation centripetal acceleration v2Ir 205 x 205/400 - 105 ft/sec2 normal G 322 ft/sec2 Thus airplane loaded 105/322 G Adding safety factor estimated loadof5G airplane weighs 25 lb plane loaded 5 G making turn wings carrying [5 x 25] lb 125 lb ignoring fuselage contribution wing panel carrying 625 lb leading edge slats carry some percentage loadsay 25% Multiplying approximately 60 lb 25% yields 15 lb force slat An additional safety factor 2 multiplied yield test load 30 lb equivalent loading 10G Since loading slat assumed uniform leading edge hinge line estimated conservatively slat would sustain 15-lb uniform load given turn Doubling load 30 lb equivalent flying 10-G turn turn radius 130 ft 140 mph Thats way outside performance airplane indicates magnitude test load involved load testing cardboard box matching slat outline filled 30 lb sand placed slat Though seems almost counterintuitive especially watching test slat sustained load Dispersed loads deceiving 4 December1992 11 R400feet $ 8/60 feet] secoed V 140 ,ph feet/cecond IKON NWST Since 1977 IKON offers largest selection giant scale kits world order kits call 1-800-327-7198 catalog fine kits send $4 00 dah Re de Add5 SaeSaesTa Futaba 9302- 4-40 Pushrods Flap Servo Robart #309 Super Point Futaba 9201 III9Hines Aileron Servo static testing made cardboard box same shape leading edge slat filled 30 pounds sand concentrated load slat system showed no signs fatigue confidence rose Tonys help devised substitute wind tunnel testing Tony made bracket hold modified Illustration 1 Slat-and-flap arrangement hingemounting pads laminated balsa ply Illustration 2 Servo horns counterclockwise rotation top pulls flap down pushes slat down wings outside car window Testing done fuselage hence aid locking pins though speed car never approached flight speed aircraft became apparent locking pins required design speed range however provide extra assurance against loading conditions place stress slat-and-flap system fully deployed servo horn positioned flap left being pulled down slat right pushed down See Illustration 1 slatand-f lap system retracted 12 Model Aviation on Fiber Reinforcement BalsaPly Slat \7/ Rap 6 RYAN PT-22 1/4 SCALE 90 STINSON SR-B 1/5 SCALE 100 PILATUS PORTER GIANT SCALE 98 P51D MIJSTANG HAND CRAFTED FREE-FLIGHT GLIDERS Best Looldag Best Flying Most DLrile Gliders Deed * READY TO FLY * Large 22 Wing Span Plug-In Reinforced Wing Unbreahabie Body Totally Adustable Tall Capale Loops Straight & Level Flight & 50 Drneter Boomerang Banks Return Thrower $1295 plus $200 S&H 15300 S&H 2 Day Delivery y Qers shipped sane day Checks must dear 30 Day Satlaleoflon Guarantee Phone/Fax 516424-mi Info RIKERAIRcRAFT70FcfwdsonAveEsatHampton NY11937 tapered slat-locking pin protrudes right side fuselage wing has yet mounted slatconditions impossible calculate before flying model Flight testing Given outstanding flight characteristics stock Yellow Aircraft F- 18 wing knew would take lot ruin planes performance Fortunately slat/flap system worked beautifully F-18s already good slow-speed characteristics actually improved no problems showed up high speeds confident going flight testing positive results made box placed test load concentrated slat safety factor used calculating load variable-camber wing system appears have worth extra building time minor modifications system should adaptable other aircraft decide include gadgets next project hope theyll work successfully VER 80 MANUFACTURERSSWAP SHOPHUNDREDS OF MODELSCONCESSIONS AIRCRAFTBOATSCARSRAILROADS INDOOR-OUTDOOR RIC CAR RACINGBOAT DEMONSTRATIONS IN OUTDOOR POOL CONTROL LINE DEMONSTRATIONSR/C HELICOPTER DEMONSTRATIONS ELECTRIC R/C PLANE DEMONSTRATIONS 9 AM-S PM SATURDAY 10 AM-S PM SUNDAY WESTERN WASHINGTON FAIRGROUNDS PUYALLUP WASHINGTON RADIO CONTROLLED MODELS December1992 13 stress-testing cardboard sandbox custom-made shape LE slat filled 30-lb load r slat-and-flap system sustained 30-lb load no signs fatigue bucket supported wing S JAN 3Oth-3lst r ADULTS $500 CHILDREN 6-12 $300 u/adult SENIOR CITIZENS $300