Air Design Ultralight Flying Object 18", Manual And Service Book

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ATTENTION: The full stall requires a lot of height and demands certain skills to recover. It is
important this manoeuvre is not practiced without qualified supervision.
It should preferably be practiced during a safety training course.
We do not recommend making this manoeuvre.
l. Deep/Parachutal Stall
The deep stall, or parachutal stall is kind of the pre-stage to a full stall. The wing has no forward
motion and a high sink speed. The pilot can enter the deep stall by applying both brakes. It is
very difficult to keep the wing in a deep stall as the UFO instantly wants to fly again: If you pull
the brakes a little too much, the glider will enter a Full Stall. If you release the brakes too much,
the glider will go back to normal flight. To practice a deep stall, it is necessary to master the full
stall first.
We advise against flying in rainy conditions . In general the UFO does not show a tendency for
a deep stall when flying in rain. But when flying in rain generally it can cause a risk of deep-
stalling. If it happens that you get into rainfall, we recommend not to perform a B-stall or Big
Ears. The best is to leave the rain as soon as possible, and to fly with both brakes released, or
even flying accelerated, as this reduces the risk of a deep stall. (The available brake travel
before entering a deep stall may be reduced significantly.)
m. Rapid decent manoeuvres
i. Spiral
The spiral dive is an effective way of making a fast descent. During the spiral dive the pilot and
glider will experience strong centrifugal forces which strain the glider. As such it should be
considered an extreme manoeuvre. Due to the rapid height loss during a spiral, pilots must
always take care that they have sufficient altitude before initiating the manoeuvre and that the
airspace is free around the pilot.
Initiation : Weight shift and smoothly pull on one brake (the same side you are weight shifting
into) so the glider goes from a normal 360-degree turn into a steep turn and from there into a
spiral dive. Once established in the spiral the descent rate and bank angle can be controlled
with weight shift and the releasing or pulling of inner brake. As the glider banks in front of the
pilot maintain the spiral by keeping the brake pressure constant, at this point weight-shift can
be neutralised. Descent is controlled by pulling more on the inner brake. A slight pull on the
outside brake helps to keep the glider stable.
Recovery : The UFO recovers from a spiral spontaneously as soon as the brakes are released
and weight shift returns to neutral. To exit, allow the spiral to slow down for a turn or two by
slowly releasing the inner brake. Once the glider starts to exit the spiral, control your descent
rate and bank angle with weight shift and the outer and/or inner brake to prevent any strong
climbs out of spiral. Always finish a spiral dive at a safe altitude.
The UFO does not show any tendency for a stable spiral. That means the glider does not
remain in spiral after releasing the brakes. If the glider should, in rare cases, remain in a stable
spiral the pilot should first weight-shift to the outside and then brake slightly more on the
outside.