Most avid gas free-flighters - even younger enthusiasts - will immediately the names in this list of Who's Who from a 1957 article in American Modeler. Carl Goldberg, Stanley Hill, Frank Ehling, John Tatone, and the others were pioneers of the free flight realm. Unlike many other model aircraft types, the variety in fuselage, wing and empennage shapes, engine downthrust and overall configurations is quite wide. These 11 profile silhouettes, even without top views to show wing and tail planforms, amply illustrates my point. Even today's winning model exhibit a similar diversity.
For the First Time ... Symposium on Free Flight Adjustment
America's Top Flyers Reveal Their Contest-Winning Secrets
No matter what new types of model flying may come along, free-flight will always be with us. For only in free-flight can there be that feeling, of complete self satisfaction in seeing your model scream heavenward and then settle gently back to earth unaided and unguided once it leaves your hands.
Whether you are a true free-flight purist or just enjoy flying free-flight models whenever the mood strikes you will agree that in free-flight there is that extra bit of "something" necessary to get contest-winning performance. No matter what meet you go to, there is always one model that zooms higher than the others, glides flatter and probably more important always flies the same flight pattern. Why? Is it the design of the model? The engine? Adjustment know-how? Little tricks the champions use? You've probably asked yourself similar questions hundreds of times.
To answer these questions for you we queried a number of top free-flight designers and champions. Among the questions were those pertaining to thrust line and surface settings, hand gliding, how to adjnst for turn in the glide and under power, pros and cons of adding weight to correct the glide angle and views on incidence changes.
To learn how Champs flight test a new model we asked how long an engine run on initial test flights, how much power, what thrust adjustments do they use and what were the adjustments on their most recent contest· winning models.
For good measure we included questions like: What are your views on the relationship of adjustment vs. design? Which is more important? What type of model is easiest to adjust - hardest?
We thank all the champions who participated in our survey and who for the first time supplied information which had always been regarded as "top secret." In presenting their views to our readers we feel that although these may differ considerably on many points all are well worth remembering the next time you fly free-flight.
Dr. Stanley D. Hill
First achieved fame flying "Amazon" designed by Mrs. Hill. Latest is series of "Hammerhead" models. Flew on International F.A.I. free flight team. Lives in Santa Barbara, Cal. "Hammerhead II" has 2 deg. positive wing incidence, zero deg. stab. setting and zero deg. thrust settings. Hand glides for loose right hand turn. Gradually increases turn to safe maximum. Accomplishes turn by tilting stab and slight right rudder. Says wing warping is dangerous and unreliable in any hot-power job. Considers wing incidence and C.G. position as fixed factors which determine model's flight characteristics and are therefore to remain unchanged, unless desired flight pattern cannot be achieved with variations of stab incidence alone. Uses 7 sec. motor run for high powered models, 15 sec. if very low powered. Initial test flights made with very low power, increasing gradually to 2/3, then to full power. Prop on forward. Tries to avoid thrust adjustment but has used up to 3 deg. side thrust. Agrees downthrust is effective in "opening up" looping tendency on low thrust models. Ineffective on high thrust line models. Flies "Hammerhead" designs in left-right pattern. Pylons right-right. Believes good design much more important than adjustment know-how. Considers high thrust line model easier to adjust due to lack of prop wash effect. Thinks the more offsets and warps used, the harder model will be to fly.
World's most famous free-flight designer, "father" of all pylon-type models. Best known pre-war designs were "Zipper" and. "Interceptor." Currently developing new free flight kit for his Chicago model concern. Model shown had 1 1/2 deg. positive wing incidence, 1/2 deg. negative stab setting, no downthrust. Hand glides for very gentle left turn. Trims model for left, left flight pattern. Uses rudder, tilting wing and tilting stab in that order as necessary to achieve proper turn. Says altering incidence angles on proven designs would depend upon last flight. On test flights, uses 7-8 sec motor run with intake tube plugged about 80%. When glide is O.K. uses side thrust to alter power turn. Does not change propeller to alter turn. Believes design furnishes basic flight capacity. Adjustment corrects errors in design and building but says it isn't always needed. Advises beginners to take time and make sure C.G. position and incidence set-up are as shown on plan. Remove warps by steaming over tea kettle. Work up gradually from low to high power and get help from experienced flyers.
Willard S. "Woody" Blanchard, Jr.
Three-time winner of National Model Plane Championship crown (1954, 1955, 1956). Tremendous contender in any free flight competition; lives in Hampton, Va. Always uses 5 deg. downthrust, approx. 5 deg. positive wing incidence and 2 deg. positive stab incidence. Builds pylon design if power loading is low. Hand glides first then trims for right-right flight pattern. Uses both rudder and thrust adjustments for power turn. Tilts stab and uses rudder for glide turn. Corrects glide angle with stab incidence. Initial test flights begin with 5 sec. engine run with propeller on backwards. Believes prop affects flight pattern but generally does not change props to alter power turn. Recommends ample dihedral and use of engine downthrust rather than tight turn to prevent looping under power. Feels beginners should build from kits, follow flying instructions supplied by designer. Says easiest model to adjust is towline glider. Hardest is free flight gas.
Donald K. Foote
Designer of the "Westerner" free flight kit, author of the well-known books, "Model Airplane Engines" and "Aerodynamics for Model Airplanes." Resides in Oakland, Cal. Uses about 1/2" positive wing incidence in 10 1/4", zero deg stab setting. Believes hand gliding from high point is very helpful as model can then be adjusted for turn as well as for flat glide. Strives for turning glide to the left only because he usually has more than one model at a time and flies all of them in the same pattern. Says any model that is stable in one direction is just as stable in the opposite direction, providing all adjustments are opposite including wing warps. Warps inside (left) wing slightly, then uses left thrust to turn model to left under power. Then uses slight amount of right rudder to slip model toward left to make dihedral more effective. Says rudder should never be turned past center to left with this method. In working out an original design, moves the C.G. according to flight characteristics. Stab incidence is altered to get model to follow flight path and not present whole bottom as frontal area to flight path. Test flies on no more than 3 sec. engine run and very little power. Adds adjustments with each flight of increased power. Claims once model is adjusted for maximum power it should never be flown on less than full power since models can only be adjusted for one speed. Finds it unnecessary to place propeller on backwards. Uses left thrust but never downthrust. Says down thrust is a dead give away to a bug in the design. Uses propeller that gives maximum thrust. Claims all his models are adjusted the same and fly the same, left-left pattern. No matter what the design, believes even poorly designed models can be adjusted to win contests but thinks good adjustments coupled to a good design have a better chance. Considers a high-wing model easiest to adjust, a low-wing model the most difficult. Says beginners should read all literature available on the subject to learn why each surface is trimmed as it is. Thinks it is a disgrace not to know the cause of a crash.
Winner of more PAA-Load contests (and watches!) than any man in history. This San Diego, Cal., flyer is a consistent winner in West Coast competitions. Model shown has 2 deg. positive incidence in wing. Zero stab. Engine has 5 deg. downthrust and 2 deg. right thrust. Hand glides only in first stage of testing to eliminate wing stall and achieve left circle. Uses tilting stab and rudder for turn and if needed floating tab on left wing panel for left turn. Never warps wings. Keeps C.G. location between 50% and 75% of mean wing chord and uses 2 deg. positive incidence. Does all adjusting with stab and engine thrust line. First power flights are made with 10 to 15 sec. motor run at 1/3 to 1/2 maximum power and propeller on backwards. Never uses propeller pitch to alter turn. Flies model in right-left pattern. Believes adjustment is secondary to a good design. Says no amount of adjusting will make a poorly designed model fly properly. Easiest models to adjust are low power to weight models. Claims most beginners start out with powered models that fly like unguided missiles, the end of the model being sure and swift.
Carl R. Wheeley
Technical Director of the Academy of Model Aeronautics, winner of the F.A.I. International free flight competition, lives in Washington, D. C. Designed famous series of "Senator" contest winners. Does not: work with degrees. Half-A models use 1/8" positive in wing, 3/32" positive in stab. Class A models 1/4" positive in wing, 1/8" positive in stab. Class B-C models 3/8" positive in wing, 1/4" positive in stab. Hand glides and strives for very slight turn. Says almost every new model turns a little even with straight settings and so on first flight lets model turn in whichever direction it tends. Prefers tilting stab to control glide turn. Uses rudder tab and tilting stab for power turn. Claims it is difficult if not impossible to determine beforehand right balance point and except for knowledge gained in flying similar models, it is much a trial and error deal. Uses variations in stab incidence as final trim after proper C.G. location has been determined through use of weight. Initial test flights made with engine running at fast four cycle for 5 to 8 seconds. No longer recommends putting prop on backwards because of tremendous difference in turning characteristics when prop is on forward. Tries to avoid offset thrust adjustments but does use some if rudder cannot cure defect. Uses same propeller. Claims changing prop often necessitates complete power flight readjustment. Prefers climb and glide in same direction whether it be left or right. Believes adjustment is far more important than design. But says this depends on what a person considers design to be. Feels changing area of rudder is changing the design but it is also adjusting model. Claims contest type models are easier to adjust than scale types.
Monticello, N. Y., designer has had more of his free flight planes kitted than any other flyer. Currently serving as consultant on design problems to American Modeler. Frank's most recent model uses 1 deg. positive wing incidence, Zero deg. stab incidence, right but no downthrust. Hand glides from shoulder height or from slope. Glide turn on high powered model is opposite to power turn. Claims that with this set-up model does not fall out as transition, but carries over like hand launched glider. Tilts stab for turn in glide, uses rudder for power turn. Controls glide angle by placing C.G. between 70% and 90% of wing chord, then adds positive to stab after glide is O.K. To retain proper glide adds weight to tail. Makes test flights with 5 to 6 sec. motor run on high powered models, 10 to 12 sec. on low powered models. Engine wide open, prop on forward for both types. Uses side thrust to produce one to two circles in 20 seconds. Has never used down thrust. Claims engine governs propeller. Uses prop that gets most from engine usually a low pitch for glow plug, higher pitch for diesel. Believes adjustment know-how is just as important as good design. Easiest model to adjust is large model with low power but feels best chance for beginner is pylon and high thrust.
Former Brooklyn Skyscraper member, achieved fame before war with his "Pacer" design. Scored new successes with his "Spacer." Now lives in Lakewood, Cal. Won International PAA-Load event at 1956 Nationals with time of 15:47.2. Still flies "Spacer" with 2 deg. positive wing incidence, zero to 1 deg. positive in stab, no downthrust. Hand glides before first test flight only. Does not fight natural turning tendency of plane but says "Spacers" generally turn to left in glide, right under power. Tilts stab to control amount of turn in glide. Corrects shallow stall or dive by adding weight. Cautions against adding positive incidence to correct stall. Says this may adversely affect smooth transition between power on and power off. Test flies with 10 sec. motor run and about 75% power with prop forward. If model noses up sharply and hangs, Sal recommends a few degrees of engine downthrust to get it to fly up instead of drag up. Chooses prop that lets engine run without "lugging" and controls turn with rudder. Advises model be allowed to age before testing. Claims model tested too soon may show completely different flight characteristics a week later, due to warps induced by additional tightening of the covering. Easiest models to adjust are those built without warps.
C. O. Wright
Topeka, Kan., model aviation activity leader, long-time modeler, former president of A.M.A. Triple-threat man in PAA-Load flying. Model shown flies with 3 deg. positive wing incidence, zero deg. stab setting and slightly left engine thrust. Hand glides for straight or slightly left turn at first. Uses tilting stab for glide turn. Controls power turn with rudder tab or by shifting entire rudder or offsets thrust. Flattens glide with wing incidence but maintains at least 3 deg. for reasonable pull out. Often adds weight for same reason. Test flights made with 8 sec. run with engine "missing." Prop on forward. Doesn't like to use offset thrust adjustments but says, after building, theory is not as important as the performance. Claims right-left flight pattern is safer with not too much right spiral. Likes best almost straight-up power path. Admits some of his best models flew right-right patterns. Believes good design is important but says two models of same design will vary due to warps etc., therefore, adjustment is highly significant. Recommends low pylon designs for beginners as easiest to adjust. Low wing designs are hardest to adjust. Claims models become more difficult to adjust as C.G. moves rearward more than 60% from leading edge of wing. Advises practice of shifting entire rudder instead of using rudder tab which he claims is more effective but also more dangerous, especially for beginners.
Former N.A.C.A. modeler now works for Convair, lives in Chino, Cal. Many winning designs to his credit; author of American Modeler's "West Coast Modeling." Uses 1/32" positive incidence for each 1" of wing chord. Zero deg. stab. setting. Hand glides many times, strives for left turn through use of tilting stab. Offsets thrust line to control power turn. Does not use rudder as it may affect glide turn. Prefers left, right pattern but does not fight model if it persists in going opposite and flys safely. Invariably adds weight prior to finishing model to get C.C. forward of 75% of wing chord. Says all his engines have leaded back plates. If necessary changes stab incidence for final trim. Initial test flights begin with 7 to 12 second engine run, low power and intake plugged to /8" diameter. Prop on forward. Believes in lots of down and right thrust on high powered models, usually builds in approximately 1/4" down and right as a start, then alters this to fit model. Does not believe in measuring in degrees, says they are generally grossly inaccurate. Agrees prop plays important part in final flight pattern. Claims lowering pitch gives right turn on pylon models, increasing pitch will cause model to go left. Does not believe a Half-A model good proving ground for model design. Says if you scale them up you are really lucky if they fly. Advises beginners to build the model to last. Remembers experts taking weeks to trim models, then flying them and winning for years.
Has qualified for International F.A.I. teams, scored numerous wins in regional and National competitions, lives in San Francisco. His timing device in use currently on free flight contest models. Flies model with 3 deg. positive wing incidence, 1 deg. positive in stab, right wing washed in 1/4"; 2 deg. left engine thrust. Hand glides before first power flight. Determines final glide trim after model has been flown. Does not fight natural turning tendency of model, never uses rudder for glide turn. Instead uses tilting stab, sometimes a floating drag tab. Adds weight to achieve proper balance. Test flies with about 10 sec. motor run, prop on forward. Reports his ships usually start off with a few degrees down thrust. Adds more or less depending on power pattern. Believes prop is very important and uses same prop through test flights. When experimenting with different props uses short motor run. Thinks pylon type model easiest to adjust, claims they hold adjustments better. Advises a very small rudder tab on hot ships. Says rudder tab takes over at high speed, does not affect the glide.
Additional contributions to this Free Flight Adjustment Symposium will appear In a subsequent "American Modeler."
Posted January 2, 2016