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with weight shift and a little outside brake. The deflation should re-inflate
spontaneously. If the deflation does not re-inflate spontaneously, apply brake on
the closed side in a smooth, progressive pumping action. Be sure not to apply too
much brake too slowly as this may risk a stall. Remember that a partly collapsed
wing has a reduced surface area and thus a higher stall speed.
SYMMETRIC (FRONT) COLLAPSE
Symmetric (frontal) collapses will normally re-open without pilot input. Assist this
process if necessary with a symmetric application of the brakes. Take care not to
apply too much brake for too long as this may stall the wing.
CRAVATTES
A cravatte occurs when a wing tip becomes stuck between the glider lines, for
example, following a bad take-off preparation. On the APAX a cravatte is unlikely
to occur. If you do get a cravatte, first control your direction. Do this by using
weight shift and enough counter-brake to stop the turn, but not too much to risk
a stall of the opposite side. Then pull down the stabilo line (STB-see line plan) until
it becomes tight. This normally frees the cravatte
.
CASCADES
Many reserve deployments and accidents are a result of a cascade of over-
corrections by the pilot. Please note that overreactions are often worse than no
input at all.
When a glider is flying through the air a laminar and turbulent airflow will form
around the surface of the wing. If the laminar airflow along the top surface is
interrupted, dangerous flight configurations follow. We call this a ‘wing stall’.
WARNING:
Full stall and tailspin are flight manoeuvres which are very dangerous
if the pilot does not react correctly. These manoeuvres must be avoided.
Moreover, it is important to recognise the stall from the very beginning, so
the pilot can prevent it with an immediate reaction.
In the following, the three different types of stalls for gliders will be described more
precisely.
