Front/symmetrical tuck collapse, Asymmetric stall (spin) – Windtech kinetik plus User Manual

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than the collapse itself. Once you have maintained a safe course, and minimized the turn
induced by the collapse, you can apply CORRECTION to re-inflate the collapsed side of
the wing by giving smooth but firm pumps on the brake on the collapsed side, holding
down the brake until the glider re-inflates. Do not give small ‘panicky’ dabs of brake to
the collapsed side of the wing as this does not really help and will make the wing take
much longer to re-inflate. Once the wing re-inflates be careful not to hold down the
brake too much, for too long, as this could stall the wing, or induce a spin.

-- front/symmetrical tuck collapse

T

his is when the whole leading edge of the wing, from the centre to the tips, collapses.

It is possible to have a front tuck on exit from a strong thermal, when using the speed
system or trimmers in turbulent conditions, hitting a (wind) shear layer, etc. Generally,
this situation does not require any pilot intervention as the glider will re-inflate quickly,
autonomously and without problem. However, if the pilot wishes to help with re-infla-
tion of the glider, this is the procedure to follow:

First, one should release the speed system (if one has it on) and pull both brakes approx-
imately 50% until the glider reopens, and then immediately release the brakes so as to
not stall the wing. After the glider has re-inflated it is always a good idea to check the
trimmer’s, to make sure that they have not been pulled open by the shock of the re-infla-
tion of he wing, and as you have suffered a collapse, it is best to make sure that the trim-
mers are in the “normal” position as it is clear that you are flying in a turbulent area!

-- asymmetric stall (spin)

It is extremely difficult to accidentally provoke a stall with the KINETIK

PLUS

, given the

glider’s very forgiving flying characteristics and extremely low stall speed, the pilot has
to really abuse the brakes to do this. Of course, one should bear in mind that the brake
travel is substantially reduced, and the stall point easier to reach when full thrust is
applied and the trimmers are in the slower “normal” flying position for take off.

In any case, it is possible for the pilot to stall the wing if, for example, when flying very

slowly (nearly at stall point) the pilot gradually releases the outer brake (the correct thing
to do) but then also applies more inside brake (on the side of the turn), thereby stalling
the inside wing. The stalled side of the wing now drops back into stall, rotating back-
wards (negative), whilst the still flying outside wing rotates forwards (positive) around
the pilot. In this case, to return to normal flight, the pilot has to raise the inside brake to
reduce the angle of attack, allowing positive airflow to return over the wing, and taking
that side of the wing out of the stall. In releasing the brake on the stalled side of the
wing (which is necessary to regain normal flight), the wing will then try to regain nor-
mal airspeed which, depending on the moment at which the spin is released and how
‘flat’ the spin was, will result in a dive which is more, or less, strong. If the wing dives
forward violently then the pilot should try to damp the dive by quickly applying a bit
more than approximately half brake (only enough to stop the dive) which should be

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