FREE FLIGHT DURATION TIPS shape give wingtips Free Flight models based bit aerodynamic theory some practicalities construction andperhaps care admiton fashion tip wing flying surface matter aerodynamic special case tip air flowing straight front rear over rest wing Instead curling up beneath wingtip rolling wrapping itself spiraling vortex trailing off tip vortex produces quite bit drag wind-tunnel test airfoils extend full width tunnel generations modelers well designers full-scale aircraft have tried number things reduce size effect tip vortex easiest way simply reduce size tip itself increasing aspect ratio ratio average chord span reduce chord tip some other aerodynamic advantages increasing wing aspect ratio certain model classes improvements construction materials over last two decades aspect ratios area-restricted events such FlA Glider FlB Wakefield FiC Power have increased dramatically typical Power model 1970s wing aspect ratio around 101 latest models pushing 181 Although increasing wing aspect ratio constantchord planform will reduce tip chord chord entire wing effective way taper wing gives wider thicker section center structural loads highest Tapering also reduces weight tips reduced inertia Light tips like light tail help improve models ability recover upset need tapered planform especially important sheeted aluminum/balsa construction used Most weight wing skins way significantly reduce tip weight reduce tip area well also holds true solid-balsa wings used handlaunch catapult gliders An alternative tapered planform elliptical planform Most people consider aesthetically pleasing shape whether Supermarine Spitfire Goldberg Sailplane An elliptical planform bit trouble build open structure almost impossible build sheeted aluminum-skinned wing solid-balsa wing about easy straight tapered wing Thats see hand-launch gliders elliptical planforms designers have gone doubletapered planform alternative elliptical planform means wing tapers slightly enter out dihedral break sharply tip double taper approximates shape elliptical planform using relatively easy-to-build straight-taper panels logical extension threepanel wing divides wing half three sections instead two outermost panel usually shortest sharply tapered Often attached angle adjoining section approximating elliptical dihedral well elliptical planform Schuemann April1999 119 double-taper wing Norm Potis Nibble 300 good example tapering structure center tip Nostalgia models such T-Bird use small tip plates popular 1950s reduce airflow up around tip Alan Abriss built Y2A version L 9, A9OovTwQ OF tONGS 1/YAW OCt00 SCALY ASS j-i-1-o 1 4 cL N s2CCF04S CO SYCSF04 FEW An early version Schuemann planform model 1930s German sailplane Frank Zaics Model Planes American Boy St o planform developed full-scale sailpianes widely used RC gliders good example three-panel approach double- triple-taper wing rear face wing main spar usually straight top view easier construction As alternative trailing edge can straight taper occurring swept-back leading edge Either way helps have some straight reference line aerodynamic reasons airfoil thickness camber usually reduced progressively center tip example wing might have center airfoil thickness 6% decreasing 55% break 45% tip Camber would likewise decrease hard way to replot airfoil break tip reducing percentage chamber thickness have airfoil plotting software packages shouldnt take too long Note merely reducing center airfoil copier would change Schuemann planform helps reduce tip vortex NFFS Book Power Models Ed Kecks FiC has narrow tip chord helps reduce tip vortices Use hightech materials allows long thin wings built amazing strength triple-taper wing Bill Cushenberrys Wakefield features turned-up tips approximate elliptical dihedral Tip wide SCHUEMANN WING PLANFORM FIT 2 AIRFLOS4 OVER AIRFCL SHAPE RaATIPE PRESSURE DISTRI6SJTIOT4 P163 LO4 SEPARAn AT TRAILING EDSE Lt*pIIi E( Inq -/ ISII L II PIG4-STRAIEUT WING AIRFLOW LEAVNG ECCE TOP FIG 5- NORMAL -rWINC TIP WITH SWEPT FORWARD TRAILING EDGE EJOTE SPAN WISE ROW rOWAROS ROOT LE*Wfl4 00CC TOP OWS - SMALL PLOW SEPARATION AT TIlE WINGTIP TRAVELS TOWARD ROOT tNIIRE SPAN MAT EFA PATE-ONCE STAPTEG THUS CREATING NIT/I OPAGANIS uir toss AKER 1ST VOCACA p \A7tvnK SWEPT LE CSTRAIGNTTE SPAN WISE FLOW IS tJE6LIDIOLL TAPERED TIP MINIMIZES VORTLT LOSSE5 FIGR MULTIPLE TAPERS I-IELPACHIEVE THE NEAR OPTIFIUMELLIPTICAL5 LIFT ESISTRIBU TION AND HELP COMBAT HIGH TIP LOSSES 120 Model Aviation 4 thickness percentage building undercambered wing approach requires making separate building boards wing panel desired washin washout built individual boards An easier approach make constant-chord building board matched shape underside wings center airfoil Building tapered wing constant-chord building board will automatically reduce camber percent terms washin washout panel can skewed slightly board Pushing tip forward will give wash out quick refresher Washin means wing panel twisted slightly leading edge tip greater angle incidence break Washout reverse giving tip less incidence break Washing out tip slightly will help reduce tip vortex Washin washout should considered deliberate design featuresnot unfortunate result sloppy construction too much dope covering called warps what about events wingspan limited Using 181 aspect ratio wing P-30 would certainly reduce tip vortices wing area would about 50 square inches what want best glide better approach P-30 PeeWee-30 go other way Use low aspect ratio possible get largest possible wing area lowest wing loading Usually results rectangular wing constant chord also gives wing easy build structurally very demandinggood attributes events intended beginners wide chord carried way out end wing tip such model will efficient high-aspect-ratio tapered wing possible answer winglets developed NASA full-scale aircraft reduce tip vortex essentially fool air thinking wing has higher aspect ratio does Winglets must carefully designed cambered effective Just sticking some flat vertical fins tips P-30 could harm good Another factor has limited use winglets just wont fit average model box rules AMA events well FlG Coupe FlJ Small Power limit wing area wingspan free build size shape wing want events high-aspect-ratio wing offers no great advantage better build moderate-aspect-ratio wing 101 121 will give needed area wing easier build down weight doesnt mean should ignore tips Tapered elliptical tips will help reduce drag well weight constant-chord wing light tips important Reduce size spars toward tips cant change size ie Nostalgia model least use lighter wood tips Hobby Supply South places number Free Flight kits supplies stocked local hobby shop limited good mail-order source wide range Free Flight merchandise Hobby Supply South Located north Atlanta close phone computer catalog includes familiar kits Peck-Polymers Aerodyne Guillow Sterling Sig Herr Engineering addition stock KeilKraft Dumas Diels Engineering DPR Models Vernon West Wings Lots scale stick-and-tissue stuff particular interest Battle Britain series Wingleader includes Spitfire Hurricane 109all 16- 20-inch-span range Although real thing few years late Battle Britain series also includes nice-looking Hawker Tempest West Wings line includes Hawker Sea Fury half-size version WA Judges 1936 Wakefield Winner L-Tec line simple foam-andplastic models designed Don Jehlik includes several nice-looking small gliders rubber models Also included catalog information about JJ Levines Model Building 101 innovative program help introduce Free Flight schools JJ has packaged tools materials needed build Delta Dart larger 20-inch-span Rubber model Great school camp projects can reach Hobby Supply South old-fashioned way writing 1720 Mars Hill Rd Acworth GA 30101 calling 770 974-0843 fax 770974-6243 E-mail hss@fly hsscom Better yet check Out Web site wwwfly-hsscom simple catpult glider can built JET-X assist kids adults Quick assembly Easy fly -PolymersPO Box710399-MA Phone 619448-1818Santee CA 92071 Fax 619448-1833Send $400 full catalog April 1999 121 IKON NWSTS 1/4 SCALE GEE BEE MODEL Y 9tJ Wing span Wt 18 lbs Power ST4500 G42-G62 Fiberglass cowl pants Decals Complete build plans hand cut parts best aaiog 01scaicaji u aL 1-208-773-9001 Kit order line 1-800-327-7198 selected wood
Edition: Model Aviation - 1999/04
Page Numbers: 119, 120, 121
Edition: Model Aviation - 1999/04
Page Numbers: 119, 120, 121
FREE FLIGHT DURATION TIPS shape give wingtips Free Flight models based bit aerodynamic theory some practicalities construction andperhaps care admiton fashion tip wing flying surface matter aerodynamic special case tip air flowing straight front rear over rest wing Instead curling up beneath wingtip rolling wrapping itself spiraling vortex trailing off tip vortex produces quite bit drag wind-tunnel test airfoils extend full width tunnel generations modelers well designers full-scale aircraft have tried number things reduce size effect tip vortex easiest way simply reduce size tip itself increasing aspect ratio ratio average chord span reduce chord tip some other aerodynamic advantages increasing wing aspect ratio certain model classes improvements construction materials over last two decades aspect ratios area-restricted events such FlA Glider FlB Wakefield FiC Power have increased dramatically typical Power model 1970s wing aspect ratio around 101 latest models pushing 181 Although increasing wing aspect ratio constantchord planform will reduce tip chord chord entire wing effective way taper wing gives wider thicker section center structural loads highest Tapering also reduces weight tips reduced inertia Light tips like light tail help improve models ability recover upset need tapered planform especially important sheeted aluminum/balsa construction used Most weight wing skins way significantly reduce tip weight reduce tip area well also holds true solid-balsa wings used handlaunch catapult gliders An alternative tapered planform elliptical planform Most people consider aesthetically pleasing shape whether Supermarine Spitfire Goldberg Sailplane An elliptical planform bit trouble build open structure almost impossible build sheeted aluminum-skinned wing solid-balsa wing about easy straight tapered wing Thats see hand-launch gliders elliptical planforms designers have gone doubletapered planform alternative elliptical planform means wing tapers slightly enter out dihedral break sharply tip double taper approximates shape elliptical planform using relatively easy-to-build straight-taper panels logical extension threepanel wing divides wing half three sections instead two outermost panel usually shortest sharply tapered Often attached angle adjoining section approximating elliptical dihedral well elliptical planform Schuemann April1999 119 double-taper wing Norm Potis Nibble 300 good example tapering structure center tip Nostalgia models such T-Bird use small tip plates popular 1950s reduce airflow up around tip Alan Abriss built Y2A version L 9, A9OovTwQ OF tONGS 1/YAW OCt00 SCALY ASS j-i-1-o 1 4 cL N s2CCF04S CO SYCSF04 FEW An early version Schuemann planform model 1930s German sailplane Frank Zaics Model Planes American Boy St o planform developed full-scale sailpianes widely used RC gliders good example three-panel approach double- triple-taper wing rear face wing main spar usually straight top view easier construction As alternative trailing edge can straight taper occurring swept-back leading edge Either way helps have some straight reference line aerodynamic reasons airfoil thickness camber usually reduced progressively center tip example wing might have center airfoil thickness 6% decreasing 55% break 45% tip Camber would likewise decrease hard way to replot airfoil break tip reducing percentage chamber thickness have airfoil plotting software packages shouldnt take too long Note merely reducing center airfoil copier would change Schuemann planform helps reduce tip vortex NFFS Book Power Models Ed Kecks FiC has narrow tip chord helps reduce tip vortices Use hightech materials allows long thin wings built amazing strength triple-taper wing Bill Cushenberrys Wakefield features turned-up tips approximate elliptical dihedral Tip wide SCHUEMANN WING PLANFORM FIT 2 AIRFLOS4 OVER AIRFCL SHAPE RaATIPE PRESSURE DISTRI6SJTIOT4 P163 LO4 SEPARAn AT TRAILING EDSE Lt*pIIi E( Inq -/ ISII L II PIG4-STRAIEUT WING AIRFLOW LEAVNG ECCE TOP FIG 5- NORMAL -rWINC TIP WITH SWEPT FORWARD TRAILING EDGE EJOTE SPAN WISE ROW rOWAROS ROOT LE*Wfl4 00CC TOP OWS - SMALL PLOW SEPARATION AT TIlE WINGTIP TRAVELS TOWARD ROOT tNIIRE SPAN MAT EFA PATE-ONCE STAPTEG THUS CREATING NIT/I OPAGANIS uir toss AKER 1ST VOCACA p \A7tvnK SWEPT LE CSTRAIGNTTE SPAN WISE FLOW IS tJE6LIDIOLL TAPERED TIP MINIMIZES VORTLT LOSSE5 FIGR MULTIPLE TAPERS I-IELPACHIEVE THE NEAR OPTIFIUMELLIPTICAL5 LIFT ESISTRIBU TION AND HELP COMBAT HIGH TIP LOSSES 120 Model Aviation 4 thickness percentage building undercambered wing approach requires making separate building boards wing panel desired washin washout built individual boards An easier approach make constant-chord building board matched shape underside wings center airfoil Building tapered wing constant-chord building board will automatically reduce camber percent terms washin washout panel can skewed slightly board Pushing tip forward will give wash out quick refresher Washin means wing panel twisted slightly leading edge tip greater angle incidence break Washout reverse giving tip less incidence break Washing out tip slightly will help reduce tip vortex Washin washout should considered deliberate design featuresnot unfortunate result sloppy construction too much dope covering called warps what about events wingspan limited Using 181 aspect ratio wing P-30 would certainly reduce tip vortices wing area would about 50 square inches what want best glide better approach P-30 PeeWee-30 go other way Use low aspect ratio possible get largest possible wing area lowest wing loading Usually results rectangular wing constant chord also gives wing easy build structurally very demandinggood attributes events intended beginners wide chord carried way out end wing tip such model will efficient high-aspect-ratio tapered wing possible answer winglets developed NASA full-scale aircraft reduce tip vortex essentially fool air thinking wing has higher aspect ratio does Winglets must carefully designed cambered effective Just sticking some flat vertical fins tips P-30 could harm good Another factor has limited use winglets just wont fit average model box rules AMA events well FlG Coupe FlJ Small Power limit wing area wingspan free build size shape wing want events high-aspect-ratio wing offers no great advantage better build moderate-aspect-ratio wing 101 121 will give needed area wing easier build down weight doesnt mean should ignore tips Tapered elliptical tips will help reduce drag well weight constant-chord wing light tips important Reduce size spars toward tips cant change size ie Nostalgia model least use lighter wood tips Hobby Supply South places number Free Flight kits supplies stocked local hobby shop limited good mail-order source wide range Free Flight merchandise Hobby Supply South Located north Atlanta close phone computer catalog includes familiar kits Peck-Polymers Aerodyne Guillow Sterling Sig Herr Engineering addition stock KeilKraft Dumas Diels Engineering DPR Models Vernon West Wings Lots scale stick-and-tissue stuff particular interest Battle Britain series Wingleader includes Spitfire Hurricane 109all 16- 20-inch-span range Although real thing few years late Battle Britain series also includes nice-looking Hawker Tempest West Wings line includes Hawker Sea Fury half-size version WA Judges 1936 Wakefield Winner L-Tec line simple foam-andplastic models designed Don Jehlik includes several nice-looking small gliders rubber models Also included catalog information about JJ Levines Model Building 101 innovative program help introduce Free Flight schools JJ has packaged tools materials needed build Delta Dart larger 20-inch-span Rubber model Great school camp projects can reach Hobby Supply South old-fashioned way writing 1720 Mars Hill Rd Acworth GA 30101 calling 770 974-0843 fax 770974-6243 E-mail hss@fly hsscom Better yet check Out Web site wwwfly-hsscom simple catpult glider can built JET-X assist kids adults Quick assembly Easy fly -PolymersPO Box710399-MA Phone 619448-1818Santee CA 92071 Fax 619448-1833Send $400 full catalog April 1999 121 IKON NWSTS 1/4 SCALE GEE BEE MODEL Y 9tJ Wing span Wt 18 lbs Power ST4500 G42-G62 Fiberglass cowl pants Decals Complete build plans hand cut parts best aaiog 01scaicaji u aL 1-208-773-9001 Kit order line 1-800-327-7198 selected wood
Edition: Model Aviation - 1999/04
Page Numbers: 119, 120, 121
FREE FLIGHT DURATION TIPS shape give wingtips Free Flight models based bit aerodynamic theory some practicalities construction andperhaps care admiton fashion tip wing flying surface matter aerodynamic special case tip air flowing straight front rear over rest wing Instead curling up beneath wingtip rolling wrapping itself spiraling vortex trailing off tip vortex produces quite bit drag wind-tunnel test airfoils extend full width tunnel generations modelers well designers full-scale aircraft have tried number things reduce size effect tip vortex easiest way simply reduce size tip itself increasing aspect ratio ratio average chord span reduce chord tip some other aerodynamic advantages increasing wing aspect ratio certain model classes improvements construction materials over last two decades aspect ratios area-restricted events such FlA Glider FlB Wakefield FiC Power have increased dramatically typical Power model 1970s wing aspect ratio around 101 latest models pushing 181 Although increasing wing aspect ratio constantchord planform will reduce tip chord chord entire wing effective way taper wing gives wider thicker section center structural loads highest Tapering also reduces weight tips reduced inertia Light tips like light tail help improve models ability recover upset need tapered planform especially important sheeted aluminum/balsa construction used Most weight wing skins way significantly reduce tip weight reduce tip area well also holds true solid-balsa wings used handlaunch catapult gliders An alternative tapered planform elliptical planform Most people consider aesthetically pleasing shape whether Supermarine Spitfire Goldberg Sailplane An elliptical planform bit trouble build open structure almost impossible build sheeted aluminum-skinned wing solid-balsa wing about easy straight tapered wing Thats see hand-launch gliders elliptical planforms designers have gone doubletapered planform alternative elliptical planform means wing tapers slightly enter out dihedral break sharply tip double taper approximates shape elliptical planform using relatively easy-to-build straight-taper panels logical extension threepanel wing divides wing half three sections instead two outermost panel usually shortest sharply tapered Often attached angle adjoining section approximating elliptical dihedral well elliptical planform Schuemann April1999 119 double-taper wing Norm Potis Nibble 300 good example tapering structure center tip Nostalgia models such T-Bird use small tip plates popular 1950s reduce airflow up around tip Alan Abriss built Y2A version L 9, A9OovTwQ OF tONGS 1/YAW OCt00 SCALY ASS j-i-1-o 1 4 cL N s2CCF04S CO SYCSF04 FEW An early version Schuemann planform model 1930s German sailplane Frank Zaics Model Planes American Boy St o planform developed full-scale sailpianes widely used RC gliders good example three-panel approach double- triple-taper wing rear face wing main spar usually straight top view easier construction As alternative trailing edge can straight taper occurring swept-back leading edge Either way helps have some straight reference line aerodynamic reasons airfoil thickness camber usually reduced progressively center tip example wing might have center airfoil thickness 6% decreasing 55% break 45% tip Camber would likewise decrease hard way to replot airfoil break tip reducing percentage chamber thickness have airfoil plotting software packages shouldnt take too long Note merely reducing center airfoil copier would change Schuemann planform helps reduce tip vortex NFFS Book Power Models Ed Kecks FiC has narrow tip chord helps reduce tip vortices Use hightech materials allows long thin wings built amazing strength triple-taper wing Bill Cushenberrys Wakefield features turned-up tips approximate elliptical dihedral Tip wide SCHUEMANN WING PLANFORM FIT 2 AIRFLOS4 OVER AIRFCL SHAPE RaATIPE PRESSURE DISTRI6SJTIOT4 P163 LO4 SEPARAn AT TRAILING EDSE Lt*pIIi E( Inq -/ ISII L II PIG4-STRAIEUT WING AIRFLOW LEAVNG ECCE TOP FIG 5- NORMAL -rWINC TIP WITH SWEPT FORWARD TRAILING EDGE EJOTE SPAN WISE ROW rOWAROS ROOT LE*Wfl4 00CC TOP OWS - SMALL PLOW SEPARATION AT TIlE WINGTIP TRAVELS TOWARD ROOT tNIIRE SPAN MAT EFA PATE-ONCE STAPTEG THUS CREATING NIT/I OPAGANIS uir toss AKER 1ST VOCACA p \A7tvnK SWEPT LE CSTRAIGNTTE SPAN WISE FLOW IS tJE6LIDIOLL TAPERED TIP MINIMIZES VORTLT LOSSE5 FIGR MULTIPLE TAPERS I-IELPACHIEVE THE NEAR OPTIFIUMELLIPTICAL5 LIFT ESISTRIBU TION AND HELP COMBAT HIGH TIP LOSSES 120 Model Aviation 4 thickness percentage building undercambered wing approach requires making separate building boards wing panel desired washin washout built individual boards An easier approach make constant-chord building board matched shape underside wings center airfoil Building tapered wing constant-chord building board will automatically reduce camber percent terms washin washout panel can skewed slightly board Pushing tip forward will give wash out quick refresher Washin means wing panel twisted slightly leading edge tip greater angle incidence break Washout reverse giving tip less incidence break Washing out tip slightly will help reduce tip vortex Washin washout should considered deliberate design featuresnot unfortunate result sloppy construction too much dope covering called warps what about events wingspan limited Using 181 aspect ratio wing P-30 would certainly reduce tip vortices wing area would about 50 square inches what want best glide better approach P-30 PeeWee-30 go other way Use low aspect ratio possible get largest possible wing area lowest wing loading Usually results rectangular wing constant chord also gives wing easy build structurally very demandinggood attributes events intended beginners wide chord carried way out end wing tip such model will efficient high-aspect-ratio tapered wing possible answer winglets developed NASA full-scale aircraft reduce tip vortex essentially fool air thinking wing has higher aspect ratio does Winglets must carefully designed cambered effective Just sticking some flat vertical fins tips P-30 could harm good Another factor has limited use winglets just wont fit average model box rules AMA events well FlG Coupe FlJ Small Power limit wing area wingspan free build size shape wing want events high-aspect-ratio wing offers no great advantage better build moderate-aspect-ratio wing 101 121 will give needed area wing easier build down weight doesnt mean should ignore tips Tapered elliptical tips will help reduce drag well weight constant-chord wing light tips important Reduce size spars toward tips cant change size ie Nostalgia model least use lighter wood tips Hobby Supply South places number Free Flight kits supplies stocked local hobby shop limited good mail-order source wide range Free Flight merchandise Hobby Supply South Located north Atlanta close phone computer catalog includes familiar kits Peck-Polymers Aerodyne Guillow Sterling Sig Herr Engineering addition stock KeilKraft Dumas Diels Engineering DPR Models Vernon West Wings Lots scale stick-and-tissue stuff particular interest Battle Britain series Wingleader includes Spitfire Hurricane 109all 16- 20-inch-span range Although real thing few years late Battle Britain series also includes nice-looking Hawker Tempest West Wings line includes Hawker Sea Fury half-size version WA Judges 1936 Wakefield Winner L-Tec line simple foam-andplastic models designed Don Jehlik includes several nice-looking small gliders rubber models Also included catalog information about JJ Levines Model Building 101 innovative program help introduce Free Flight schools JJ has packaged tools materials needed build Delta Dart larger 20-inch-span Rubber model Great school camp projects can reach Hobby Supply South old-fashioned way writing 1720 Mars Hill Rd Acworth GA 30101 calling 770 974-0843 fax 770974-6243 E-mail hss@fly hsscom Better yet check Out Web site wwwfly-hsscom simple catpult glider can built JET-X assist kids adults Quick assembly Easy fly -PolymersPO Box710399-MA Phone 619448-1818Santee CA 92071 Fax 619448-1833Send $400 full catalog April 1999 121 IKON NWSTS 1/4 SCALE GEE BEE MODEL Y 9tJ Wing span Wt 18 lbs Power ST4500 G42-G62 Fiberglass cowl pants Decals Complete build plans hand cut parts best aaiog 01scaicaji u aL 1-208-773-9001 Kit order line 1-800-327-7198 selected wood
