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C-line stall
This manoeuvre is occasionally recommended as a descent technique.
It is instigated by symmetrically pulling the C-risers. The wing loses its
forward momentum and begins to descend. This manoeuvre is basi-
cally possible, but should only be practised with a qualified instructor.
Collapses
Asymmetric collapses
When flying into strong turbulence, one side of the paraglider may
collapse. This happens because the turbulence causes the angle
of attack on that side to decrease to the extent that lift is no longer
generated, the lines de-pressure and the wing collapses.
Such a collapse normally only affects a small part of the whole span
and the wing will not react significantly. During larger collapses which
affect 50 percent or more of the span, the wing will clearly react: due
to the increased drag of the collapsed side, the glider will begin to turn
towards that side. Simultaneously the wing will pitch forward becau-
se of the reduced area carrying the wing loading, i.e. because this
causes that side of the wing to accelerate. The pilot can prevent this
turn and forward pitch by braking the uncollapsed side of the wing.
Braking the uncollapsed side is essential, especially near the ground.
This manoeuvre should be practised with induced collapsed at height,
preferably during an SIV/pilotage course.
Then the sink rate can be varied using the inner and outer brake.
If the pilot’s weight remains on the outside, releasing the inner brake is
sufficient to continuously slow the rotational movement of the glider.
Exiting the spiral is then performed as described above.
If the pilot strongly weight-shifts to the centre, the glider may lock into
the spiral, regardless whether the brakes have been released. In this
case symmetrical braking or braking on the outside may help, as well
as weight-shifting to the outside.
In conclusion: it is essential to practise this manoeuvre gently and in
stages. The exit must be controlled. Important safety information:
• if the pilot wishes to reduce the spiral or rotational movement, it is
recommended that the first action is to pull the outside brake, rather
than to release the inside brake;
• the pilot must be aware of the physical demands of rotation (vertigo)
and acceleration (g-forces).
• if the pilot weight-shifts to the inside of the rotation, the wing may
lock into the spiral;
• because of the fast descent rate, the pilot must constantly monitor
the height above ground and exit the spiral in good time.
These physical
demands can be
simulated in a g-force
trainer. We recom-
mend such g-force
training to all pilots.
If the open side is
braked too much
the glider may spin
– see the section on
spins.
!
Summary of Contents for MENTOR 4
Page 1: ...Manual _DE _EN...
