Great Planes Spirit 2-Meter Sailplane Kit - GPMA0530 - Manual (Page 35)

spin that will not over stress the airframe but it will enable it
to lose altitude very quickly. This is especially helpful if the
sailplane gets sucked into a cloud or it gets too high to see.
The twirling action will give the sun a better chance of
flashing off of the wing and catching your attention. When
you are high enough and want to leave the thermal, add a little
down trim to pick up some speed and fly 90 degrees to the
direction of the wind. If you are not real high and want to find
another thermal, you may want to look upwind of the last
thermal. The same source that generated this thermal is
probably producing another. Just watch out for "sink" it is
often found behind and between thermals.
As you might expect, with all this air rising, there is also
air sinking. This air is the sailplane pilot's nightmare that can
really make soaring challenging. "Sink" is usually not as
strong as the thermals in the same area, but it can be very
strong. Down drafts of many hundreds of feet per minute are
common on a good soaring day. These down drafts can make
a sailplane look like it is falling out of the air. Because of this,
it is important that you do not let the sailplane get too far
downwind.
When encountering sink, immediately turn and fly 90
degrees to the direction of the wind (towards you if possible).
Apply a little "down elevator'' and pick up some speed to get
out of the sink as fast as possible. Every second you stay in
the sink is precious altitude lost.
gusts and dump the extra altitude and speed at the last second.
They can also be used to help control your skid. Opening the
spoilers will stop the plane from sliding a little quicker. You
can also ''steer'' the plane while it is sliding along the ground.
Don't expect
to be able to "horse it around'' but you can gain
valuable inches by using the rudder to guide it towards the
spot as it slides to a stop. Be very careful not to "ground
loop'' the plane since you will lose your landing points if the
plane flips over.
Concentrate! - Keep your eye on your sailplane during your
contest flights. Have a helper or your spotter watch the other
sailplanes in the air. Sometimes your sailplane will wiggle so
quickly or gently that you may miss it if you are not paying
close attention. If you find a productive thermal, don't leave
it because your helper tells you that someone else has found
a different one.
Know your sailplane! - Learn what your sailplane will and
won't do and fly within this envelope. This will allow you to
ride thermals downwind while knowing when you have to
head back to make your landing safely.
Learn from the wind! - Keep track of which way the wind is
blowing. If the wind suddenly shifts, there is some thermal
action fairly close to you. The air is probably being either
sucked up into a thermal or falling out of some sink. In either
case it is often a good idea to fly in the direction the wind is
blowing if your sailplane is in the general area. This will take
you towards a thermal if there is one or away from the sink,
both of which are desirable.
POINTERS FOR CONTEST FLYING
Pay Attention! - Pay close attention to the sailplanes flying
before you, watch them and try to establish where and when
the thermals are being formed. Thermals are often formed in
cycles and can be fairly regular so if you keep track of the time
intervals you will have a pretty good idea of when and where
a thermal may be generated.
Watch the birds! - Thermals suck up small insects that many
birds love to eat. A bunch of swallows flying around in one
area may indicate a thermal. Soaring birds (hawks, vultures,
eagles etc.) are the best thermal indicators. They not only
show you where the thermal is but they also show you where
the center is. These "Masters of the sky" will often fly right
along with sailplanes.
Practice those landings! - Most thermal contests are won or
lost during the landing. Establish a particular landing pattern
and try to stick to it for all landings. Learn to shift your pattern
to account for the wind and particular flying Field character-
istics. Spoilers can be very useful during contest landings.
They allow you to bring the sailplane in for a landing higher
or faster than normal to guard against any last minute sink or
SLOPE SOARING
FLYING
Slope soaring is a type of flying that is very popular in
hilly regions and along the coasts. This type of soaring is
possible when the wind is blowing directly up a hill or cliff.
As the wind hits the slope it is forced up producing lift which
can be utilized by real sailplanes, hang gliders, birds and even
model sailplanes.
To be able to slope soar, you need a slope with a smooth
piece of land (or water) out in front of it and a breeze blowing
pretty close to straight up the slope. The higher and steeper
the hill or cliff the better. Also the larger and smoother the
land out in front the better. The air flowing along hits the hill,
is forced up and can generate a very large area of lift. Behind
the hill is a large area of turbulent air that can be very
dangerous to try to fly in. The faster the wind is blowing the
stronger the lift and turbulence will be.
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