Preflighting, sticks and wind
On this single-stick Hitec NEON transmitter, the pushing the stick forward (A) causes the elevator to deflect downward and the nose of the plane to pitch down. Pulling it back (B) pitches the nose up. Pulling the stick to the right (C) moves the rudder to the right and in three-channel airplanes, typically banks the plane into a right turn. Pulling the stick to the left (C), banks the plane to the left. Note the throttle channel is controlled by a lever on the back of the transmitter (E).
In the October issue of FLY RC, we discussed what to look for in a first RC model, where and under what conditions it is best to fly, and why and how you should practice on an RC flight simulator on a computer (not any flight simulator, but one made for RC — they are quite different). In PART II, we learn some basic flying techniques.
CHECKING OUT A MODEL BEFORE FLIGHT
Although it is the instructor's responsibility to check out the airplane before flying, you should always go through a checklist on your own. It’s good practice: when you are Pilot In Command, it will be your responsibility and it’s handy to already know what to check for. Full scale pilots use a check list and I had one taped on the back of my transmitter until I memorized it.
For electrics, here's what I look for before letting the plane take off.
• With everything off, make sure that there's nothing loose by tilting the plane in all directions
• Check that the control surfaces have little or (best) no play in them
• Make sure your frequency is clear - that nobody else is using it and that your antenna is fully extended
• If the frequency is clear, turn on the transmitter, and check the meter or lights to see that it is fully charged
• Turn on the receiver. If you have not done so recently, do a range check as per the instructions that came with the transmitter
• Check that all control surfaces move smoothly and in the proper directions.
• Make sure that the motor and gearbox operate smoothly and without excessive vibration.
If any of these tests fail, correct the problem before flying. Many models have been lost because the pilot dismissed a problem as being “not too bad”. This is a moment when maturity (at any age) and judgment count.
If my plane has good ground handling (a steerable tail or nose wheel is helpful), I will often taxi a figure 8 to see if the vibration will loosen anything. I then line up with the runway, stop the motor (or idle it if it's a gassie), think about where I intend to fly, and then take off. But we've gotten ahead of ourselves. If you are with an instructor, the instructor should take off the first few times, and as soon as the plane is high enough, hand over the controls to you.
Some planes do not have landing gear and must be hand launched, which is model airplane speak for thrown - or at least tossed. Again, it is best to have an experienced pilot demonstrate, but the main errors are throwing at too high an angle upward, throwing downward, throwing too softly, and (rarely) throwing so hard as to damage the plane. Most planes need a launch that is level or very slightly (very slightly!) slanted up. Some people throw the airplane so that the wings are not level when it is released, requiring expert correction and luck to avoid an immediate crash. If you are teaching and flying by yourself, it is very hard to throw the airplane and then get your hands quickly to the controls. If you can't fly with a teacher or experienced RC pilot, at least bring a friend to help.
THE WIND, FRIEND AND FOE
When learning to fly, windless days are best. For one thing, you don't have to think about the wind. But on most days there is some wind, and often there is too much wind. Just how much wind is too much depends on the model you are flying and on your experience level. Again, this is something you can learn from an expert or through repeated, possibly painful experience. Wind can move along a straight path, but it can also be gusty or turbulent. At our club's favorite schoolyard, the wind usually comes from an unobstructed direction, and moves smoothly. But some days it comes across the school building and then across our runway. On a blustery day with wind coming over the school building, planes can be suddenly tossed about or smashed into the ground by the wind's irregular motion.
Above: this Airtronics VG400 transmitter has a typical "mode 2" setup. The left stick controls throttle (full forward delivers full throttle and pulling it back cuts throttle). The left stick, swung side-to-side, controls rudder. The right stick on a four-channel airplane typically controls aileron (side-to-side) and elevator (forward and back). Ailerons offer added control in the roll axis-we will discuss this in greater detail in future articles.
This combination shows left rudder, left aileron and up elevator.
One of the advantages of flying from the same field is that you get to know how the wind behaves. A small wind speed meter (anemometer) can be a help. If the flying was good with the wind from the west at 5 mph on one day, it will be almost certainly be good if the wind is from the same direction at the same speed another day.
The wind can be helpful if you use it wisely. For example, if there is any wind, ALWAYS take off and land into the wind. Here's why: What counts in keeping an airplane up is its airspeed, that is, the speed with which it is moving through the air. If you have a 10 mph breeze down the runway, and your plane is moving at a 10 mph groundspeed into the wind, that's 20 mph of airspeed. What counts in damaging an airplane is the speed with which it hits something. That's its ground speed. For takeoffs and landings you want adequate airspeed at low ground speed. By taking off and landing into the wind, you are using the wind to your advantage.
Here is another wind danger: Unless you are careful to keep the plane upwind of you at all times, it is very easy for a plane to move with the wind until it gets so far downwind that you can’t bring it back. This is particularly true with powered sailplanes that are not designed to penetrate the wind (that is, "floaters" that fly relatively slowly). When I was a novice pilot, this happened to me and to most other flyers I know. It happens with surprising rapidity. The plane can move downwind and away from you quickly (with respect to the ground, where you are standing), but only grind its way slowly upwind, on its way back to you. As a beginner, if you don't have full control over where the airplane is going, and you make a mistake trying to bring it back, it may just drift farther away.
At our club we usually fly from the downwind end of the field, face into the wind, and keep our planes in front of us.
Taking off and landing when the wind is coming from the side of the airplane is strictly for advanced fliers. And even they try to avoid this situation if possible. So should you.
Steve Ellis, flight instructor at the FLYRC club in Southbury, CT, teaches a scout to fly a trainer.
THE BUDDY BOX
Some beginners find that learning to fly is aided by using a buddy box. This is a combination of two transmitters. One, operated by the teacher, is called the "master", and unless the teacher operates and holds a special, spring-loaded, switch, it controls the airplane. The master is connected by an electrical cord to another transmitter, called the “slave” that is operated by the student. The slave unit controls the airplane only when the teacher holds the switch. If the student gets into trouble, the teacher has only to release the switch and can then control the plane and restore it to a safe position and attitude.
If no buddy box is available, the teacher usually stands next to the student, and if there is a problem, will take the transmitter from the student and operate the airplane. Sometimes this is inconvenient, and on rare occasions takes so long that the teacher cannot save the plane.
In the next column we will discuss some basic flight techniques. Safe landings!
Links
Airtronics, www.airtronics.net,
(714) 978-1895.
Hitec RCD USA, Inc.
www.hitecrcd.com, (858) 748-6948.
