Bob Meuser Super-Bird Our Two-View-of-the-Month shows latest model using built-up Construction Jim Walters US World Champs Nordic Team earlier built up Go-Bird sheetcovered version Sno-Bird put him top position team Taft finals year ago premature release bad air World Champs kept him Out running doesnt reflect quality model construction article about Sno-Bird will appear future issue ModelAviation Photo above L Lang 42 Model Aviation j spar web tip washout 4 4I 2 3 08 i7r - 2I~ 8 fl4e 7 4 2i4 7iiK 4 sq spruce Mod Benedek 7457-d22 ThreadIi sht spruce 3 -sht sq 161881 32 2_____ I 32 8 Towhook modified Hatschek Wing wires dia kdio pin 3 3 Fuselage pod faces - core SUPERBIRD CLASS FIA JIM WALTERS 975 USA TEAM Ii MEUSER 75 Max-Aid Circle-Tow Device glance literature has piled up over past five years about various circle-tow catapult-launch line-keeping devices towline gliders leaves impression part master plan contrived Devil himself either condemn hapless modeler eternity fussing cantankerous hardware instead engaging enjoyable pursuits b render modeler totally perma nently mad Fortunately two series articles have ap peared recently British publications make some sort order out chaos Ex-World Champ Elton Drew Aeromodel ler another Editors Free Flight News set stage Ill first describe function original Russian system going details hardware next Ill de scribe Elton Drews variation theme marketed under name Max-Aid think will become extremely popular start towing upwind light line tension causes rudder deflect straightahead position model follows like well-trained dog provided lead properly like well-trained dog trainer Relax towline magic begins rudder deflects beyond its glide-turn position model turns tightly small diameter circles circles small enough dont have en danger limb lung following towline remains attached towhook until tell unhook later game As model comes around head-to-wind take slack again tow model straight rudderto top line process repeated until a thermal finds model b have go bathroom c starve death Despite fun having decide launch strong tug linesay 3 7 lbcauses a secret spring release line keeper line next goes slack will released towhook b rudder deflect slightly away straighttow position zoom launch catapult launch mode pull like crazy model veers side slacken line model having speed greatly excess its glide speed zooms up spiraling climb gaining additional altitude oh 10 20 feet release towline puts rudder glide circle position original Russian designs rather complicated European-made version has available US Ed Turner writing sold Out future supplies uncertain Watch classified ads Free Flight NFFS Digest design Bob Hatschek functionally similar easier make appeared January 1974 issue Flying Models kit castings Hats chek towhook tail hardware sold Jim Crocket Replicas $695 plus $100 postage handling Elton Drews Max-Aid Circle Tow Device appears first inspection compro mise no zoom launch rudder po sition zoom launch can achieved nevertheless biasing straight tow rudder position slightly using proper technique according Elton no towline keeper ~1 3 OG 55% 24 4 -t l8_1 unlatch Russian system Rather Elton uses spring-and-ring device twang hook called Upon uponthe extremely sudden release line tension letting knot slip fingers extended spring collapses causing hook attached end spring twang itself out ring attached circle-tow device following further description letter Elton Drew Maxaid unit came being realized circular-tow aspirants have either facilities time ability produce own hardware intention provide glider fliers opportunity obtain simple effective circular-tow device reasonable cost unit fact development system described September issue Aeromodeller Part III series Circular Tow incorporates several improvements units compactness 1-3/16 sq 7/32 light weight 8 grams less /3 oz suit virtually size glider A/l upwards adjustments made external model circular tow facility can locked Out willfor example wind too strongenormously extending versa tility system system has opinion several advantages offer over complex Rus sian system simpler offset-arm systems considerably versatile either Im biased Let explain further problem encountered Russian system flown gusty conditions sometimes encountered England believe right US premature unwanted catapult turn worse unwanted unexpected releasing line-keeping latch Adjusting Russian system over come difficulties can lead problems release still air offset hook used conjunction twang hook does provide facility accurately leading model direction desired tow ing speed Maxaid unit does give catapultturn rudder position ensures trouble never arises unwanted catapult turn occurring mentioned above However catapult launching can achieved utilizing high line tension careful biasing straighttow trim correct technique nutshell model equipped Maxaid Circular Tow unit versatile compe tition machine enabling employ tactics best suited situation moment calm air has circular-tow capability aid searching waiting lift abso lutely dead air height gain catapult launch can used advantage light drift can circle away down wind choice assessing own air stealing thing marked competition upwind perhaps importantly avoiding downdrafts indicate Alternatively wind little stronger can maintain sta tion merely staying straight-tow mode Should wind too brisk comfort circular-tow can lock out circular-tow function fly conventionally End commercial think informative Maxaid Circle-Tow System including necessary hardware can purchased US residents $850 airmail postpaid NFFS Supplies 4200 Gregory St Oakland CA 94619 can purchased 350 plus postage Maxaid Modelling Products 2 Downfield Close Alveston Bristol B512 2NJ England Thrust Bearing Indoor Style Ray Harlan 15 Happy Hollow Rd Wayland Mass 01778 offers thrust bearings Indoor models com plete prop shaft four sizes double bearings ensures true-running prop badly knotted rubber prop shaft simply drops rear element bearing rather snapping shaft cannot come Out unintentionally Price 75 plus postage order three time postage house New Event Proposed Now circle-tow zoom-launch has become height fashion lets carry step further propose new event called Towline Pattern towline remains attached model times Contestants judged according skill execute certain prescribed tow ing maneuvers plus few optional ones Gone forever piggybacking goating losing models flying-site problems Launch tow straight upwind 50 yds Execute circle circle-tow mode Bring model directly overhead Execute three consecutive circle CT mode drifting downwind Negotiate prescribed Tow-Slalom course details announced Optional maneuver Square circles figure eights suggested Mock zoom launch towline attached recovery Construction finish appearance timing perfect model DTs im mediately after recovering zoomlaunch Bonus points awarded spot landings think Im kidding put teeth proposal will offer trophyThe Meuser Memorial Trophyfor such event held 1976 US Free Flight Champs Well try sandwich between Engine Taching Model Retreival events Engine Mount Im getting sick sick sick pushing Jim Crockets nifty free-flight hard ware keeps coming Out such neat stuff can scarcely help myself Latest Old-Timer Engine Mount whole thing continued page 66 January1976 43 variation basic Russian circle-tow zoom-launch device came Czechoslovakia Right Simple no-nonsense front end Walters Sno-Bird variation Hatschek-ssyle towhook Photo Bob Meuser proposed judging format Points 5 5 10 10 20 20 20 10 100 Elton Drews circle tow unit hardware Jim Crocketts nifty Old-Timer engine mount will take Forster 29 O&R 23 K&B Torpedo x DAVE LINSTRUMS STARSTREAM 0 ULTRA SIMPLE CONSTRUCTION ALL BALSA AND PLY PARTS MACHINE OR DIE CUT 48 INCH WINGSPAN AUTO-RUDDER CONTROL FULL SIZE ILLUSTRATED STEP BY STEP PLAN FLYING INSTRUCTIONS WINNER OF THE FAI/CIAMINCLUDED INTERNATIONAL DESIGN $1195 COMPETITION FOR YOUTH GLIDEF IDWEST PRODUCTS CO 400 South Indiana StHobartIndiana 46342 RC Sport/Van Putte continued page 18 Fig 1 shows what happens ground track airplane turn varying wind conditions load factor held con stant level coordinated turn load factor directly related bank angle aircraft very simple equation Load Factor X Cosine Bank Angle ll 3600 turn shown demonstrate what hap pens both downwind upwind turn figure can also used visualize what happens during turns wind make seem dangerous Consider first airplane going downwind starts 1800 turn pilot notes airplane going fur ther downwind desires increases bank angle load factor What may happen next pilot will continue increase bank angle until airplane stalls out crashes what about airplane going upwind starts 1800 turn pilot banks airplane comfortable no-wind bank angle discovers heading relative speed airplane suddenly changing much rapidly expected loses orientation over-rolls airplane ground Neither maneuver inherently dangerous lack understanding about what air plane will wind can severely unsettle pilot particularly beginner lowspeed trainer airplane since effects wind greater slower airplanes two things remember flying wind 1 Increase bank angle over normal amount turn downwind heading made Gradually reduce bank angle airplane swings wind 2 Decrease bank angle no-wind amount turn upwind heading made Gradually increase bank angle airplane comes around downwind Try it works Next month Ill present some wind effects vertical maneuvers last few weeks have testing new product called PoweR/Charge SP Systems Marietta Ga combined nickel-cadmium battery discharger-charger field tester havent made com prehensive test unit seems advertised have used batteries two radio systems old questionable airborne pack cases PoweR/Charge progressively increased discharge time indicating increased capacity Especially striking capacity increase old battery pack After initial charge old 475-ma pack should have discharged least 2 hours 10 minutes first discharge lasted 1 hour 40 minutes second dis charge 2 hours 4 minutes third dis charge lasted 2 hours 20 minutes Subsequent discharges pack hovered around 2 hours 30 minutes Similar less startling capacity increases occurred other battery packs tested future com prehensive review will published Have seen new book beginners called Basics Radio Control Modeling Fred Marks co-authors book Model Aviation editor Bill Winter Fred town couple weeks ago business pre sented copy review remarkably well done piece work book includes chapters tools materials radio equipment engines airplanes boats cars other models like way its written photography has quality often seen model publications address 12 Connie Dr Shalimar Fla 32579 FF Duration/Meuser continued page 43 can purchased $695 can buy individual parts unit accommodates Forster 29 O&R 23 K&B Torpedo primarily flying parts nicely polished unit makes attractive display too Weight 294 gramsa thin hair over ounceand overall length 2 info write Jim 1442 N Fruit Ave Fresno CA 93728 Call Papers National Free Flight Society soliciting papers 1976 NFFS Symposium held 1976 Nats Papers will published 1976 Symposium vol ume whether author able present paper personally Nats Papers should cover some aspect science art free-flight models including technical studies practical design engineering applied models new unusual model aircraft developments historical items Both indoor outdoor freeflight modeling developments included Please send proposed papers Ray Harlan 15 Happy Hollow Rd Wayland Mass 01778 Send title proposed paper together abstract 200 words or complete paper available considered ab stracts should submitted Feb 15 1976 Book Review A ero -Modeller Annual 1975-76 review general model aviation book free-flight column Well well skip RC CL stuff judge solely its free-flight content sign times perhaps first Annual Ive seen paperback price has doubled two years UK price trans lates $450 what actual USA price will remains seen Compared what get money buy say $600 worth magazines imagine will judge worth money drawings A P Lloyd usual top quality Most model plans have appeared other publications would have subscribe magazine news letter world have seen before plans count includes 17 FAI-class models smattering others Most articles original about dozen directly related free flight including series three finishing overview Pennyplane activity world-wide plenty plans Dave Lin strum photo-story covering dozen unusual engines such Elf flat-six rotary valve four-stroke Dooling turned 28000 rpm cover other John Daddy Warbucks Pond himself complete Old-Timer course SAM 01 license plate address 4200 Gregory St Oakland Calif 94619 66 Model Aviation
Edition: Model Aviation - 1976/01
Page Numbers: 42, 43, 66
Bob Meuser Super-Bird Our Two-View-of-the-Month shows latest model using built-up Construction Jim Walters US World Champs Nordic Team earlier built up Go-Bird sheetcovered version Sno-Bird put him top position team Taft finals year ago premature release bad air World Champs kept him Out running doesnt reflect quality model construction article about Sno-Bird will appear future issue ModelAviation Photo above L Lang 42 Model Aviation j spar web tip washout 4 4I 2 3 08 i7r - 2I~ 8 fl4e 7 4 2i4 7iiK 4 sq spruce Mod Benedek 7457-d22 ThreadIi sht spruce 3 -sht sq 161881 32 2_____ I 32 8 Towhook modified Hatschek Wing wires dia kdio pin 3 3 Fuselage pod faces - core SUPERBIRD CLASS FIA JIM WALTERS 975 USA TEAM Ii MEUSER 75 Max-Aid Circle-Tow Device glance literature has piled up over past five years about various circle-tow catapult-launch line-keeping devices towline gliders leaves impression part master plan contrived Devil himself either condemn hapless modeler eternity fussing cantankerous hardware instead engaging enjoyable pursuits b render modeler totally perma nently mad Fortunately two series articles have ap peared recently British publications make some sort order out chaos Ex-World Champ Elton Drew Aeromodel ler another Editors Free Flight News set stage Ill first describe function original Russian system going details hardware next Ill de scribe Elton Drews variation theme marketed under name Max-Aid think will become extremely popular start towing upwind light line tension causes rudder deflect straightahead position model follows like well-trained dog provided lead properly like well-trained dog trainer Relax towline magic begins rudder deflects beyond its glide-turn position model turns tightly small diameter circles circles small enough dont have en danger limb lung following towline remains attached towhook until tell unhook later game As model comes around head-to-wind take slack again tow model straight rudderto top line process repeated until a thermal finds model b have go bathroom c starve death Despite fun having decide launch strong tug linesay 3 7 lbcauses a secret spring release line keeper line next goes slack will released towhook b rudder deflect slightly away straighttow position zoom launch catapult launch mode pull like crazy model veers side slacken line model having speed greatly excess its glide speed zooms up spiraling climb gaining additional altitude oh 10 20 feet release towline puts rudder glide circle position original Russian designs rather complicated European-made version has available US Ed Turner writing sold Out future supplies uncertain Watch classified ads Free Flight NFFS Digest design Bob Hatschek functionally similar easier make appeared January 1974 issue Flying Models kit castings Hats chek towhook tail hardware sold Jim Crocket Replicas $695 plus $100 postage handling Elton Drews Max-Aid Circle Tow Device appears first inspection compro mise no zoom launch rudder po sition zoom launch can achieved nevertheless biasing straight tow rudder position slightly using proper technique according Elton no towline keeper ~1 3 OG 55% 24 4 -t l8_1 unlatch Russian system Rather Elton uses spring-and-ring device twang hook called Upon uponthe extremely sudden release line tension letting knot slip fingers extended spring collapses causing hook attached end spring twang itself out ring attached circle-tow device following further description letter Elton Drew Maxaid unit came being realized circular-tow aspirants have either facilities time ability produce own hardware intention provide glider fliers opportunity obtain simple effective circular-tow device reasonable cost unit fact development system described September issue Aeromodeller Part III series Circular Tow incorporates several improvements units compactness 1-3/16 sq 7/32 light weight 8 grams less /3 oz suit virtually size glider A/l upwards adjustments made external model circular tow facility can locked Out willfor example wind too strongenormously extending versa tility system system has opinion several advantages offer over complex Rus sian system simpler offset-arm systems considerably versatile either Im biased Let explain further problem encountered Russian system flown gusty conditions sometimes encountered England believe right US premature unwanted catapult turn worse unwanted unexpected releasing line-keeping latch Adjusting Russian system over come difficulties can lead problems release still air offset hook used conjunction twang hook does provide facility accurately leading model direction desired tow ing speed Maxaid unit does give catapultturn rudder position ensures trouble never arises unwanted catapult turn occurring mentioned above However catapult launching can achieved utilizing high line tension careful biasing straighttow trim correct technique nutshell model equipped Maxaid Circular Tow unit versatile compe tition machine enabling employ tactics best suited situation moment calm air has circular-tow capability aid searching waiting lift abso lutely dead air height gain catapult launch can used advantage light drift can circle away down wind choice assessing own air stealing thing marked competition upwind perhaps importantly avoiding downdrafts indicate Alternatively wind little stronger can maintain sta tion merely staying straight-tow mode Should wind too brisk comfort circular-tow can lock out circular-tow function fly conventionally End commercial think informative Maxaid Circle-Tow System including necessary hardware can purchased US residents $850 airmail postpaid NFFS Supplies 4200 Gregory St Oakland CA 94619 can purchased 350 plus postage Maxaid Modelling Products 2 Downfield Close Alveston Bristol B512 2NJ England Thrust Bearing Indoor Style Ray Harlan 15 Happy Hollow Rd Wayland Mass 01778 offers thrust bearings Indoor models com plete prop shaft four sizes double bearings ensures true-running prop badly knotted rubber prop shaft simply drops rear element bearing rather snapping shaft cannot come Out unintentionally Price 75 plus postage order three time postage house New Event Proposed Now circle-tow zoom-launch has become height fashion lets carry step further propose new event called Towline Pattern towline remains attached model times Contestants judged according skill execute certain prescribed tow ing maneuvers plus few optional ones Gone forever piggybacking goating losing models flying-site problems Launch tow straight upwind 50 yds Execute circle circle-tow mode Bring model directly overhead Execute three consecutive circle CT mode drifting downwind Negotiate prescribed Tow-Slalom course details announced Optional maneuver Square circles figure eights suggested Mock zoom launch towline attached recovery Construction finish appearance timing perfect model DTs im mediately after recovering zoomlaunch Bonus points awarded spot landings think Im kidding put teeth proposal will offer trophyThe Meuser Memorial Trophyfor such event held 1976 US Free Flight Champs Well try sandwich between Engine Taching Model Retreival events Engine Mount Im getting sick sick sick pushing Jim Crockets nifty free-flight hard ware keeps coming Out such neat stuff can scarcely help myself Latest Old-Timer Engine Mount whole thing continued page 66 January1976 43 variation basic Russian circle-tow zoom-launch device came Czechoslovakia Right Simple no-nonsense front end Walters Sno-Bird variation Hatschek-ssyle towhook Photo Bob Meuser proposed judging format Points 5 5 10 10 20 20 20 10 100 Elton Drews circle tow unit hardware Jim Crocketts nifty Old-Timer engine mount will take Forster 29 O&R 23 K&B Torpedo x DAVE LINSTRUMS STARSTREAM 0 ULTRA SIMPLE CONSTRUCTION ALL BALSA AND PLY PARTS MACHINE OR DIE CUT 48 INCH WINGSPAN AUTO-RUDDER CONTROL FULL SIZE ILLUSTRATED STEP BY STEP PLAN FLYING INSTRUCTIONS WINNER OF THE FAI/CIAMINCLUDED INTERNATIONAL DESIGN $1195 COMPETITION FOR YOUTH GLIDEF IDWEST PRODUCTS CO 400 South Indiana StHobartIndiana 46342 RC Sport/Van Putte continued page 18 Fig 1 shows what happens ground track airplane turn varying wind conditions load factor held con stant level coordinated turn load factor directly related bank angle aircraft very simple equation Load Factor X Cosine Bank Angle ll 3600 turn shown demonstrate what hap pens both downwind upwind turn figure can also used visualize what happens during turns wind make seem dangerous Consider first airplane going downwind starts 1800 turn pilot notes airplane going fur ther downwind desires increases bank angle load factor What may happen next pilot will continue increase bank angle until airplane stalls out crashes what about airplane going upwind starts 1800 turn pilot banks airplane comfortable no-wind bank angle discovers heading relative speed airplane suddenly changing much rapidly expected loses orientation over-rolls airplane ground Neither maneuver inherently dangerous lack understanding about what air plane will wind can severely unsettle pilot particularly beginner lowspeed trainer airplane since effects wind greater slower airplanes two things remember flying wind 1 Increase bank angle over normal amount turn downwind heading made Gradually reduce bank angle airplane swings wind 2 Decrease bank angle no-wind amount turn upwind heading made Gradually increase bank angle airplane comes around downwind Try it works Next month Ill present some wind effects vertical maneuvers last few weeks have testing new product called PoweR/Charge SP Systems Marietta Ga combined nickel-cadmium battery discharger-charger field tester havent made com prehensive test unit seems advertised have used batteries two radio systems old questionable airborne pack cases PoweR/Charge progressively increased discharge time indicating increased capacity Especially striking capacity increase old battery pack After initial charge old 475-ma pack should have discharged least 2 hours 10 minutes first discharge lasted 1 hour 40 minutes second dis charge 2 hours 4 minutes third dis charge lasted 2 hours 20 minutes Subsequent discharges pack hovered around 2 hours 30 minutes Similar less startling capacity increases occurred other battery packs tested future com prehensive review will published Have seen new book beginners called Basics Radio Control Modeling Fred Marks co-authors book Model Aviation editor Bill Winter Fred town couple weeks ago business pre sented copy review remarkably well done piece work book includes chapters tools materials radio equipment engines airplanes boats cars other models like way its written photography has quality often seen model publications address 12 Connie Dr Shalimar Fla 32579 FF Duration/Meuser continued page 43 can purchased $695 can buy individual parts unit accommodates Forster 29 O&R 23 K&B Torpedo primarily flying parts nicely polished unit makes attractive display too Weight 294 gramsa thin hair over ounceand overall length 2 info write Jim 1442 N Fruit Ave Fresno CA 93728 Call Papers National Free Flight Society soliciting papers 1976 NFFS Symposium held 1976 Nats Papers will published 1976 Symposium vol ume whether author able present paper personally Nats Papers should cover some aspect science art free-flight models including technical studies practical design engineering applied models new unusual model aircraft developments historical items Both indoor outdoor freeflight modeling developments included Please send proposed papers Ray Harlan 15 Happy Hollow Rd Wayland Mass 01778 Send title proposed paper together abstract 200 words or complete paper available considered ab stracts should submitted Feb 15 1976 Book Review A ero -Modeller Annual 1975-76 review general model aviation book free-flight column Well well skip RC CL stuff judge solely its free-flight content sign times perhaps first Annual Ive seen paperback price has doubled two years UK price trans lates $450 what actual USA price will remains seen Compared what get money buy say $600 worth magazines imagine will judge worth money drawings A P Lloyd usual top quality Most model plans have appeared other publications would have subscribe magazine news letter world have seen before plans count includes 17 FAI-class models smattering others Most articles original about dozen directly related free flight including series three finishing overview Pennyplane activity world-wide plenty plans Dave Lin strum photo-story covering dozen unusual engines such Elf flat-six rotary valve four-stroke Dooling turned 28000 rpm cover other John Daddy Warbucks Pond himself complete Old-Timer course SAM 01 license plate address 4200 Gregory St Oakland Calif 94619 66 Model Aviation
Edition: Model Aviation - 1976/01
Page Numbers: 42, 43, 66
Bob Meuser Super-Bird Our Two-View-of-the-Month shows latest model using built-up Construction Jim Walters US World Champs Nordic Team earlier built up Go-Bird sheetcovered version Sno-Bird put him top position team Taft finals year ago premature release bad air World Champs kept him Out running doesnt reflect quality model construction article about Sno-Bird will appear future issue ModelAviation Photo above L Lang 42 Model Aviation j spar web tip washout 4 4I 2 3 08 i7r - 2I~ 8 fl4e 7 4 2i4 7iiK 4 sq spruce Mod Benedek 7457-d22 ThreadIi sht spruce 3 -sht sq 161881 32 2_____ I 32 8 Towhook modified Hatschek Wing wires dia kdio pin 3 3 Fuselage pod faces - core SUPERBIRD CLASS FIA JIM WALTERS 975 USA TEAM Ii MEUSER 75 Max-Aid Circle-Tow Device glance literature has piled up over past five years about various circle-tow catapult-launch line-keeping devices towline gliders leaves impression part master plan contrived Devil himself either condemn hapless modeler eternity fussing cantankerous hardware instead engaging enjoyable pursuits b render modeler totally perma nently mad Fortunately two series articles have ap peared recently British publications make some sort order out chaos Ex-World Champ Elton Drew Aeromodel ler another Editors Free Flight News set stage Ill first describe function original Russian system going details hardware next Ill de scribe Elton Drews variation theme marketed under name Max-Aid think will become extremely popular start towing upwind light line tension causes rudder deflect straightahead position model follows like well-trained dog provided lead properly like well-trained dog trainer Relax towline magic begins rudder deflects beyond its glide-turn position model turns tightly small diameter circles circles small enough dont have en danger limb lung following towline remains attached towhook until tell unhook later game As model comes around head-to-wind take slack again tow model straight rudderto top line process repeated until a thermal finds model b have go bathroom c starve death Despite fun having decide launch strong tug linesay 3 7 lbcauses a secret spring release line keeper line next goes slack will released towhook b rudder deflect slightly away straighttow position zoom launch catapult launch mode pull like crazy model veers side slacken line model having speed greatly excess its glide speed zooms up spiraling climb gaining additional altitude oh 10 20 feet release towline puts rudder glide circle position original Russian designs rather complicated European-made version has available US Ed Turner writing sold Out future supplies uncertain Watch classified ads Free Flight NFFS Digest design Bob Hatschek functionally similar easier make appeared January 1974 issue Flying Models kit castings Hats chek towhook tail hardware sold Jim Crocket Replicas $695 plus $100 postage handling Elton Drews Max-Aid Circle Tow Device appears first inspection compro mise no zoom launch rudder po sition zoom launch can achieved nevertheless biasing straight tow rudder position slightly using proper technique according Elton no towline keeper ~1 3 OG 55% 24 4 -t l8_1 unlatch Russian system Rather Elton uses spring-and-ring device twang hook called Upon uponthe extremely sudden release line tension letting knot slip fingers extended spring collapses causing hook attached end spring twang itself out ring attached circle-tow device following further description letter Elton Drew Maxaid unit came being realized circular-tow aspirants have either facilities time ability produce own hardware intention provide glider fliers opportunity obtain simple effective circular-tow device reasonable cost unit fact development system described September issue Aeromodeller Part III series Circular Tow incorporates several improvements units compactness 1-3/16 sq 7/32 light weight 8 grams less /3 oz suit virtually size glider A/l upwards adjustments made external model circular tow facility can locked Out willfor example wind too strongenormously extending versa tility system system has opinion several advantages offer over complex Rus sian system simpler offset-arm systems considerably versatile either Im biased Let explain further problem encountered Russian system flown gusty conditions sometimes encountered England believe right US premature unwanted catapult turn worse unwanted unexpected releasing line-keeping latch Adjusting Russian system over come difficulties can lead problems release still air offset hook used conjunction twang hook does provide facility accurately leading model direction desired tow ing speed Maxaid unit does give catapultturn rudder position ensures trouble never arises unwanted catapult turn occurring mentioned above However catapult launching can achieved utilizing high line tension careful biasing straighttow trim correct technique nutshell model equipped Maxaid Circular Tow unit versatile compe tition machine enabling employ tactics best suited situation moment calm air has circular-tow capability aid searching waiting lift abso lutely dead air height gain catapult launch can used advantage light drift can circle away down wind choice assessing own air stealing thing marked competition upwind perhaps importantly avoiding downdrafts indicate Alternatively wind little stronger can maintain sta tion merely staying straight-tow mode Should wind too brisk comfort circular-tow can lock out circular-tow function fly conventionally End commercial think informative Maxaid Circle-Tow System including necessary hardware can purchased US residents $850 airmail postpaid NFFS Supplies 4200 Gregory St Oakland CA 94619 can purchased 350 plus postage Maxaid Modelling Products 2 Downfield Close Alveston Bristol B512 2NJ England Thrust Bearing Indoor Style Ray Harlan 15 Happy Hollow Rd Wayland Mass 01778 offers thrust bearings Indoor models com plete prop shaft four sizes double bearings ensures true-running prop badly knotted rubber prop shaft simply drops rear element bearing rather snapping shaft cannot come Out unintentionally Price 75 plus postage order three time postage house New Event Proposed Now circle-tow zoom-launch has become height fashion lets carry step further propose new event called Towline Pattern towline remains attached model times Contestants judged according skill execute certain prescribed tow ing maneuvers plus few optional ones Gone forever piggybacking goating losing models flying-site problems Launch tow straight upwind 50 yds Execute circle circle-tow mode Bring model directly overhead Execute three consecutive circle CT mode drifting downwind Negotiate prescribed Tow-Slalom course details announced Optional maneuver Square circles figure eights suggested Mock zoom launch towline attached recovery Construction finish appearance timing perfect model DTs im mediately after recovering zoomlaunch Bonus points awarded spot landings think Im kidding put teeth proposal will offer trophyThe Meuser Memorial Trophyfor such event held 1976 US Free Flight Champs Well try sandwich between Engine Taching Model Retreival events Engine Mount Im getting sick sick sick pushing Jim Crockets nifty free-flight hard ware keeps coming Out such neat stuff can scarcely help myself Latest Old-Timer Engine Mount whole thing continued page 66 January1976 43 variation basic Russian circle-tow zoom-launch device came Czechoslovakia Right Simple no-nonsense front end Walters Sno-Bird variation Hatschek-ssyle towhook Photo Bob Meuser proposed judging format Points 5 5 10 10 20 20 20 10 100 Elton Drews circle tow unit hardware Jim Crocketts nifty Old-Timer engine mount will take Forster 29 O&R 23 K&B Torpedo x DAVE LINSTRUMS STARSTREAM 0 ULTRA SIMPLE CONSTRUCTION ALL BALSA AND PLY PARTS MACHINE OR DIE CUT 48 INCH WINGSPAN AUTO-RUDDER CONTROL FULL SIZE ILLUSTRATED STEP BY STEP PLAN FLYING INSTRUCTIONS WINNER OF THE FAI/CIAMINCLUDED INTERNATIONAL DESIGN $1195 COMPETITION FOR YOUTH GLIDEF IDWEST PRODUCTS CO 400 South Indiana StHobartIndiana 46342 RC Sport/Van Putte continued page 18 Fig 1 shows what happens ground track airplane turn varying wind conditions load factor held con stant level coordinated turn load factor directly related bank angle aircraft very simple equation Load Factor X Cosine Bank Angle ll 3600 turn shown demonstrate what hap pens both downwind upwind turn figure can also used visualize what happens during turns wind make seem dangerous Consider first airplane going downwind starts 1800 turn pilot notes airplane going fur ther downwind desires increases bank angle load factor What may happen next pilot will continue increase bank angle until airplane stalls out crashes what about airplane going upwind starts 1800 turn pilot banks airplane comfortable no-wind bank angle discovers heading relative speed airplane suddenly changing much rapidly expected loses orientation over-rolls airplane ground Neither maneuver inherently dangerous lack understanding about what air plane will wind can severely unsettle pilot particularly beginner lowspeed trainer airplane since effects wind greater slower airplanes two things remember flying wind 1 Increase bank angle over normal amount turn downwind heading made Gradually reduce bank angle airplane swings wind 2 Decrease bank angle no-wind amount turn upwind heading made Gradually increase bank angle airplane comes around downwind Try it works Next month Ill present some wind effects vertical maneuvers last few weeks have testing new product called PoweR/Charge SP Systems Marietta Ga combined nickel-cadmium battery discharger-charger field tester havent made com prehensive test unit seems advertised have used batteries two radio systems old questionable airborne pack cases PoweR/Charge progressively increased discharge time indicating increased capacity Especially striking capacity increase old battery pack After initial charge old 475-ma pack should have discharged least 2 hours 10 minutes first discharge lasted 1 hour 40 minutes second dis charge 2 hours 4 minutes third dis charge lasted 2 hours 20 minutes Subsequent discharges pack hovered around 2 hours 30 minutes Similar less startling capacity increases occurred other battery packs tested future com prehensive review will published Have seen new book beginners called Basics Radio Control Modeling Fred Marks co-authors book Model Aviation editor Bill Winter Fred town couple weeks ago business pre sented copy review remarkably well done piece work book includes chapters tools materials radio equipment engines airplanes boats cars other models like way its written photography has quality often seen model publications address 12 Connie Dr Shalimar Fla 32579 FF Duration/Meuser continued page 43 can purchased $695 can buy individual parts unit accommodates Forster 29 O&R 23 K&B Torpedo primarily flying parts nicely polished unit makes attractive display too Weight 294 gramsa thin hair over ounceand overall length 2 info write Jim 1442 N Fruit Ave Fresno CA 93728 Call Papers National Free Flight Society soliciting papers 1976 NFFS Symposium held 1976 Nats Papers will published 1976 Symposium vol ume whether author able present paper personally Nats Papers should cover some aspect science art free-flight models including technical studies practical design engineering applied models new unusual model aircraft developments historical items Both indoor outdoor freeflight modeling developments included Please send proposed papers Ray Harlan 15 Happy Hollow Rd Wayland Mass 01778 Send title proposed paper together abstract 200 words or complete paper available considered ab stracts should submitted Feb 15 1976 Book Review A ero -Modeller Annual 1975-76 review general model aviation book free-flight column Well well skip RC CL stuff judge solely its free-flight content sign times perhaps first Annual Ive seen paperback price has doubled two years UK price trans lates $450 what actual USA price will remains seen Compared what get money buy say $600 worth magazines imagine will judge worth money drawings A P Lloyd usual top quality Most model plans have appeared other publications would have subscribe magazine news letter world have seen before plans count includes 17 FAI-class models smattering others Most articles original about dozen directly related free flight including series three finishing overview Pennyplane activity world-wide plenty plans Dave Lin strum photo-story covering dozen unusual engines such Elf flat-six rotary valve four-stroke Dooling turned 28000 rpm cover other John Daddy Warbucks Pond himself complete Old-Timer course SAM 01 license plate address 4200 Gregory St Oakland Calif 94619 66 Model Aviation