Radio Control: Helicopters

U Helicopters El Walt Schoonard SOUTH CENTRAL Helicopter Cham pionships hosted Mid-Arkansas Radio Control Society Little Rock Arkansas will take place July 23 24 headquarters motel will Holiday Inn north Little Rock Arkansasphone 501 758-1440 Novice Intermediate Ex pert Scale Beginners Trophies merchandise through third place con test directors Doug Wilcox Bill Runyan contest pre-empted Helicopter Nats have gra ciously set new date contest going great contest directed two great guys dont miss further information contact Doug Wil cox 206 Sierra Madre North Little Rock Arkansas 72118phone 501 758-8626 Jet Ranger Plastic Tail Cone very neat plastic tail cone Part #3913 available Jet Ranger saves lot work over carving out wood has built-in lens light However has very weak mounting lug soon breaks Continued page 52 24 Model Aviation Left Swashplate anti-rotation standoff Tac-Tron installation Right Free-floating blades showing dual pivot points Blades perfectly manufactured require no balancing pictures page relate Walts modifications Jet Ranger Left Delta hinge showing 7 degrees tilt automatic pitch added center itself Right Remounting pitch rudder servos permit installa tion swashplate rear-control mechanism photographs page taken author Left Standard Kavan parts used Forward cyclic bellcrank drives rear belicrank Forward rear collective bellcranks coupled collective servo Right Servo tray transmission assembled helicopter adjust collective throttle relationship 1st RC Masters Class 1st RC Advanced 1st RC Novice 1st RC Sport Scale 1st Formula Pylon 1st Quarter Midget Pylon 1st CL Stunt Open 1st CL Stunt Senior 1st CL Stunt Junior 1st CL Combat O & Sr 1st CL Slow Comb Op & Sr 1st CL Carrier II Op Jr Sr 1st CL Carrier Jr & Sr 1st CL Class D Speed Open 1st CL Class C Speed Jr & Sr 1st CLCIassB Speed Op & Sr 1st CL Cl Speed Op Sr Jr 1st CL Formula 40 Open 1st CL Class B Proto Jr 1st FF Class B Open 1st FF Class C Open HIGH PERFORMANCE * COMPETITION PROVEN * THIN RIGID BLADES OF HARD MAPLE WOOD * SUPERBLY FINISHED COMPtETELY FUEL PUOOF SPECIAL PRO SERIES 2 FOR RC-FREE FLIGHT CONTROL LINE DIAPITCHPRICE 6%3489 63499 733A4119 83Y456129 94566% 77%139 10467149 106W 8W149 106EW159 114677. 7% 7% 8159 116EW169 11%67169 126179 125W179 1356219 1456249 1556309 164%6389 W WIDE BLADE 6W EXTRA WIDE SERIES 400 B FOR SPEED NG ADVANCED DESIGN NO 1 IN PYLON RACING LEADING SPEED RECORD HOLDER OF ALL TIMES RC PYLON RACING DIA PITCH PRICE 5%3%4119 7 55%6 129 7 SN 5YN 6N129 8% 6%6%7 7%7%169 9 6%7 7%7%169 CONTROL LINE SPEEDS RACING DIA PITCH PRICE 4%6%7119 455%119 6788%129 77% 10% 11139 889149 89N 9%N149 8%77%149 912 13199 N NARROW Letters Editor continued page 5 fered customers sending orders APO/FPO addresses am sure such action dealers espe cially AMA would earn undying appreciation modelers world over because mencan modelers over world Richard Gadarin CW4 US Army APO NY R C Helicopters/Schoonard continued page 24 off vibration simple cure problem zap two V8 X 1/4 X ood blocks inside mounting tabs fit fuselage can drilled tapped 4-40 small sheetmetal screws makes very secure mount simple Free Floating Main Rotor Blades very hard time-consuming things setting up Jet Ranger has setting rotor-blade lead lag does take great deal time process accomplish perfect lead lag includes blade tongues have bad habit splitting blades slight upset answer problems free-floating blades Ernie Huber has done rolls loops free-floating blades Green ville last year several crashes due engine failure though heli copter sustained severe damage time no damage done blades have experimenting dualpivot points main rotor blades theory calm hot weather need rotor disc area windy weather less disc area pivot holes drilled apart disc can increased decreased 1 inch es simply installing blades dif ferent hole has worked really well have found setting requires re tracting blades However minor problem takes couple Continued page 78 52 Model Aviation OUT-PERFORMS ALL OTHERS AT THE 1976 NATIONALS Above Tail-rotor control modifications Alouette smooth silk easy make BelowSoft aluminum shrouds added Alouette around muffler engine improve cooling NB COMMAND Baron inYou 1 HB Engines Now enjoy kinds flying forget about stalling HB Engines precisionmade power performance reliability lowest idling speeds HB Engine includes Perry carburetor Plus several models offer Perry Directional Porting increased power up 1500 RPMs Let HB precision maneuverability speed satisfy Baron complete catalogue see local dealer write NB ENGINES HELM UT BERNHARDT PRECISION MOVEMENTS CO PO Box 6 New Canaan CT 06840 Dealership inquiries invited RC Helicopters/Schoonard Continued page S2 minutes correct blades have using Jet Ranger discovered Bill Youmans Lakeland Florida far smoothest flier have ever seen constantly trying make helicopter fly smoother theory being blades flex too much stiffer blades mean smoother flight Well right also owner set blades around After several long distance phone calls located 14 setsall USA blades completely assembled finished balanced far finest blades have ever seen have since gotten 100 sets need some drop line Swashplate Mounting Control Jet Ranger have flown seen flown would porpoise up down high-speed flight coming wind blamed too sensitive setup pilot error servo centering built newest made special ef fort keep everything up best pos sible standards However porpoising still apparent Some local heli copter pilots including Bill Youmans Norm Holland myself have marked up lot napkins over long lunches try ing solve problem contention along has problem caused swashplate being mounted three points rear swashplate could float around will problem also apparent fore aft control helicopter does something its own can fact have lost control blades sketches drew out very complicated discourage ment followed discouragement problem still unsolved However finally worked out sketch looked like would work came home work night made up mind make mods stay up until did photos column will show did indeed re quire some hard work end result well worth effort Other board remount servos parts standard Kavan parts readily available removed slop swashplate also porpoising fast flight feel helicopter now same roll axis pitch axis mounting swashplate required different anti-rotation device picture shows simple standoff tached aluminum-bearing box two ball devices standoff other swashplate rear point off swashplate has two brass balls longer screw holding anti-rotation device horizontal swashplate lift-off position remounting collective tailrotor servos required turned around end end moved mixtrim bar back l/s inches amount cut off tail-rotor control rod required no retrimming enough interest shown mod will make parts step-by-step procedure available package Carburetor-Collective Relationship carburetor opening can preset outside helicopter mounting output shaft vise nylon gear facing up mount entire transmission assembly bottom side up nylon gear end output shaft hook up carburetor linkage throttle servo Now setting collective control transmitter lift off throttle trim full can set barrel opening everything outside helicopter Kraft engine barrel half open lift off full open full col lective engine shut off full low throt tle full low trim person saw easy wondered hadnt thought it takes basically lazy trying find easier way Rotor-Head Mods have telling would write about Bill Youmans head mods However has given permission yet very good friend therefore shall have honor wishes will say however mod makes Jet Ranger hover hands off strong winds puts fly-bar work has great deal hover stability breaks down 35% Hiller 65% Bell control fly-bar blade relationship have system Jet Ranger picture shows perfectly steady hovering very strong wind very first flight Hopefully Ill able give setup later Alouette Mods Ray Hostetler N214E sent some pictures tail rotor-con trol mod Alouette very sim ple really works great have flying Alouette have no doubt loss tail-rotor control due limited amount available mod see picture will give end end control smooth silk uses Kavan tail-rotor bellcrank four links put Alouette works great also sent pictures cooling mods Alouette also works very well want information drop him line Ray Hostetler Box 363 EMC Harrisonburg VA 22801 Next months column will cover super helicopter finish inside out What materials flying trying hard enough Walt Schoonard 2080 Sharon Rd Winter Park FL 32789 78 Model Aviation 203 966-8781