Dynaflite DYFA2018 - Manual (Page 28)

circle you will be swept along with it. Be careful
when thermaling that you don't get so far downwind
you can't make it back to the field to land.
If the sailplane is flying along straight and all of
a sudden turns, let the plane continue to bank
(you may have to give it some rudder to keep it
banking) until it has turned 270° (3/4 of a full
circle). Straighten out the bank and fly into
whatever turned the plane. If you encounter lift,
and you won't every time, start circling just as
you did when flying directly into a thermal.
Thermals are generated all day long, but the
strongest thermals are produced when the sun
is directly overhead. 10:00 am - 2:00 pm seems
to be the best time to get those "killer"
thermals. Some of these thermals can be very
large and you may find it hard to get out of
them. If you find yourself getting too high, don't
dive the plane to get out of the lift. Sailplanes
are very efficient aircraft and they will build up
a lot of speed and could "blow up" in the rough
air of a thermal.The easiest way to lose altitude
is to apply full rudder and full up elevator. This
will put the plane into a tight 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° to the direction of the wind. If you
are not really 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" which 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° 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.
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
characteristics. Spoilers can be very useful
during contest landings. They allow you to
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