George M. Myers
Radio Technique
Instructor Pilot
The mechanics of RC flying are quite simple. The student pilot must learn to see what the airplane is doing and believe it. A certain amount of eye-hand coordination must be developed. The student also needs to understand some principles of aerodynamics and kinematics in order to be able to predict what the machine will do.
What must the instructor pilot do? The most important thing he must do is build up the student's confidence. He has other tasks as well, which we will discuss below.
One of the photos shows John Kleisler with a .29-powered biplane which he has designed and built. John's father, Philip, has been my friend for over 20 years. During most of that time, Phil has concentrated on designing, building, and flying RC sailplanes. When John took an interest in flying with him, then started building and flying his own powered RC designs, Phil brought John to me for instruction.
I soon discovered that John and Phil had already built several powered RC aircraft and that they had encountered a range of problems. In fact, their experiences were a microcosm of the growth of the RC hobby. Beginning with a model which was essentially a "stick-and-tissue" free-flight type (occasionally disturbed by RC), they had progressed to a two-channel .29, then to this biplane. Each model had its characteristic problems, and they had spent quite a bit of time repairing and revising their designs.
"See if you can fly it," was the challenge offered to me one foggy Friday afternoon. It was the biplane. I performed a preflight inspection, pointed out some bits and pieces that could be improved, decided that the machine was flyable, and took them out to the runway. After a bit of time spent getting the engine under control, we began taxi tests. This revealed some landing gear problems which we also fixed. The fog thickened to a drizzle, but they had come to fly, so we flew. Big discovery for me—the biplane was tail-heavy! Exciting! I got it down again in one piece.
Two D-cell batteries from my flashlight were strapped to the nose for balance. That controlled the pitch oscillations. Then we discovered that there wasn't enough power in the ailerons to overcome the twist in the wing. When I added rudder to lift the wing, the plane skidded sideways into the ground. They went home to make repairs and improvements.
We tried again. I could fly the plane, but it had too many problems to be used as a trainer. Tom Hunt flew it and suggested that a larger fin would improve "Dutch roll" resistance.
Since both wings were held on by rubber bands, I had spent a lot of time adjusting before each flight. (I like to have the same wing area on each side of the plane.) John marked the wings, added fin area, and made other suggested improvements. He also added wing struts to keep the gap constant. We began to make progress. (Instructor pilots usually have to double as test pilots, and that includes diagnosing problems and suggesting solutions.)
More of this followed, and bit by bit the plane developed into a very nice trainer. Handling characteristics improved, and John began to learn to fly.
John began showing up at our lunchtime flying sessions. Each session was devoted to a specific subject: straight-and-level flight, constant-altitude turns, S-turns out and back, loops, landing pattern, takeoffs and landings, one-, two-, and three-axial rolls, trimming the aircraft, engine adjustments, stall turns—John picked up on each subject in turn, persevered, and was making full flights (takeoff to landing) in about two weeks. He learned rapidly on a plane of his own design.
It makes the teaching effort worthwhile when that happens.
During this period, Howard Sherman came along too, with his Goldberg Sr. Falcon. Howard's problems were different. We spent some flights learning how many rubber bands were needed on the wing. Why don't the manufacturers put that information on the plans? My heart skipped several beats several times when, at various times, the plane jumped around violently in flight because the wing had lifted or shifted. I became adept at chopping the throttle and making cautious landings.
Then the radio stopped working two minutes into a flight. We later found two exhausted cells in the transmitter pack and a crystal socket in the receiver which had been filled with solder, then drilled out, at the factory! I surmise that electrical contact to the crystal was intermittent due to loss of contact pressure in the drilled-out socket. I was extremely lucky to get the plane down in one piece. (Soldered-in crystals are safer, and Howard's is now soldered in.)
During another training session, Howie got into trouble and handed me the box. In doing so, he hit the aileron dual-rate switch. Naturally the D/R was dialed to "minimum." Since the ailerons were very slow even at full rate, at low rate I got the impression that the aileron servo had failed. I made a rudder/elevator/throttle landing; fortunately without damage.
The point of all this is not to show how great a flier I am, but to illustrate that when you take on the role of instructor, you have to be prepared for the unexpected.
One of the "unexpected things" can be the vast difference between the last airplane you flew and the next one you will fly. I found that my flying deteriorated when I switched between Howie's Falcon and John's biplane for alternate flights, for instance.
Instructors have to learn fast. When most of your recent flying has been done on three-channel, Cessna-type airplanes, you really aren't ready for a fast, neutral, four-channel airplane. At least, I'm not. This was made painfully evident to me when Bubba Spivey let me fly his Javelin at the Fun-Fly following the 1986 Nats. Bubba had a powerful .40 where a .25 was meant to be, and he had the ailerons set for about two rolls per second.
When I flew across the sun, I ducked my eyes behind the bill of my cap and put in "by feel" what should have been a gentle, banked turn. It wasn't. It was a Split-S, and when I spied the airplane in the wrong part of the sky diving for the ground, I got very busy trying not to crash. After that was sorted out, I spent two flights bringing my reaction time up to match the airplane.
I liked the Javelin well enough to buy one. Bubba Spivey is the manufacturer of Lanier RC Models, P.O. Box 458, Oakwood Rd., Oakwood, GA 30566 (telephone 404/532-6401), and the Javelin is the newest of his 90% RTF airplanes. The point here is that one of your students is bound to show up with something like this to learn on. Will you be ready for it?
One of my cherished memories is that of test flying Joe Thompson's airplane. It looked pretty ordinary—a .25-powered tractor cabin monoplane with trike gear. The only things out of the ordinary were the ailerons, which were mounted where you would expect to see flaps.
After completing the usual preflight checks, I took it off and started making trim adjustments. It was a little nose-heavy, but otherwise OK. I tried the ailerons. They made the plane lean a little, but that was all. I tried the elevators. With the power available, there was not enough to loop. I tapped the rudder—and got two-and-a-half snap-rolls before I could get my thumb back. That started my adrenaline flowing!
Time to land. I set half throttle and tried to trim it for descent. It fell like a rock! After a few more attempts, I landed with full back-stick and about 80% throttle, ending the landing roll right at my feet. The spectators thought, "It flies good." Little did they know.
Joe went on to modify the airplane until it flew like any other. I always wished he hadn't. I wanted to keep that plane around—just for visiting hot-shot pilots to try.
If you seriously intend to help someone learn to fly RC, you should spend some time flying your own airplane when it is badly out of trim. Push the trims all the way to one end, then practice making figure eights, crosswiring every time on the point of a convenient cloud in the sky. Then make some takeoffs and landings with it still out of trim. It is good training for you in preparation for the next student who will show up with a plane that can't be trimmed in flight.
Next, do the same thing with the CG moved back until the airplane is almost unflyable. Do it with the CG moved so far forward that you can barely take off! More good training. It teaches you to recognize—and deal with—the kind of problems you will face. Just for the record, I have flown airplanes which had the CG out in front of the wing (and they weren't canards), and I have flown them with the CG behind the 50% point (not much fun). If you are faced with a new model and don't know where it should balance, try 20% behind the wing leading edge. If it's a biplane, 20% behind the leading edge of the top wing.
If you have dual-rate controls, practice with the dual rate set to minimum to simulate in-flight failure of a servo. (Guess where I got that idea?)
I prefer to have "too much control" available for first flights, so I set up the pushrods for as much as possible (within reason). Beginners usually set up "too little control." I don't know why; they just do.
Get the throttle right before the first flight. Your best friend can be a throttle that will die the engine on command. I can't remember how many students have presented me with a brand-new engine (in a brand-new airplane) which would bog on low throttle plus low trim (but they keep doing it). New engines won't idle. Then there is the nervous student who shuts off the receiver—just before launching the plane. It always produces a crash. This has happened to me three times in 30 years. I hate those gadgets which put the switch inside the transmitter and will cause you to guess whether the wire should be pulled out or pushed in to fly. We really must train ourselves to wiggle the control stick and verify that the control surfaces respond before every flight. And we have to train our students the same way. Insist on it.
I really believe that we all should be flying redundant radios. (I've been talking about them for the last couple of months.) It won't happen until some manufacturers start offering packaged redundant systems. Ask for them. Ask your dealer: "Why don't you stock redundant radios?" Write to the manufacturers and ask the same question. They'll sell anything that you will buy. And we'll all be safer for it.
I hope you have found this piece entertaining. If it has started you thinking about the responsibility that you accept when you offer to become an instructor pilot, then writing it has been worthwhile.
George M. Myers 70 Froehlich Farm Rd., Hicksville, NY 11801
Transcribed from original scans by AI. Minor OCR errors may remain.
