
.
Thermals are normally small near the ground and tend to increase in diameter the higher up they go. To get into a thermal,
we must first gain some altitude. There are two commonly used methods of launching a sailplane into the air.
HIGH-START:
A high-start is made up of surgical tubing and nylon cord. Its purpose is to "sling-shot" the glider into the air like a large
rubber band launched model. High-starts come in several different sizes to match the class of the sailplane being flown - a
standard class hi-start is recommended for the RISER 100. The standard class high-start usually consists of 100 feet of
rubber surgical tubing and 350 feet of nylon cord (although some brands may differ slightly). The surgical tubing is
fastened to a stake pounded into the ground. The other end of the tubing is then tied to the nylon cord, while the other end
of the nylon cord has a small parachute attached to it. The high-start is layed out on the ground directly into the wind. The
parachute end of the high start is attached to the sailplane's towhook. Start walking backwards with the model, stretching
the high-start as you go. Go back until the high-start has been stretched to a maximum of 800 feet.
With the sailplane pointed at the stake, raise the nose to approximately 30 degrees and level the wings. Firmly toss the
sailplane into the air. Feed in a small amount of up elevator after the launch and the sailplane will begin to climb to the
maximum height of the high start. If the sailplane veers to the left or right correct it with opposite rudder. DO NOT OVER
CONTROL! If it constantly veers from side to side and is hard to control, you are probably holding too much up elevator.
Back off a little to regain good directional control. As the sailplane reaches the top, the line should drop off by itself. If it
doesn't, feed in a little down elevator to allow the sailplane to dive slightly and the line will fall off. Pull back on the elevator
to level off so you can start trimming for the flattest glide.
WINCH:
A winch is a battery operated device that uses an electric motor to drive a large spool that reels in the long towline. There
is no rubber surgical tubing involved. As the line is reeled in, it pulls the sailplane up to altitude. The speed of the winch is
normally controlled by the glider pilot using a foot pedal as he flies the model with his hands. Most competition oriented
sailplane enthusiasts prefer a winch launch over a high-start simply because they can control the speed that the line is
reeled in and thus better control the speed and pull on their model.