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increase in brake line tension. Up until the
wing starts to fall back the pilot may
resume normal flight by simply releasing
the brakes.
Spin
The negative spin occurs when one side
of the wing is stalled while the other is still
flying. This can happen when, if flying very
slowly, one brake is pulled quickly to
below the seat. When the glider starts to
spin, it will turn quickly around the vertical
axis, with the stalled side flying
backwards. To recover from a spin, simply
release the brake on the stalled side. The
glider will immediately speed up and, most
likely, suffer an asymmetric collapse.
Recover as described above.
If you suspect that a spin is imminent then
immediately release the inside brake. The
glider will accelerate smoothly and resume
normal flight with little altitude loss.
Wingovers
Wingovers are induced by flying
alternating turns; each time letting the
pendulum effect increase the bank angle.
BEWARE! The UP Kibo is a agile
glider, and it is quite easy to get
to an excessively high angle
of bank in just a few turns.
Practice wingovers gently at
first, as there is a chance of quite
large collapses at high bank angles.
Also notice that a wingover flown with
more than 135 degrees bank angle is
classified as illegal aerobatics in some
countries!
Emergency Steering
If for some reason the UP Kibo cannot be
controlled with the brakes, for example if
the brake handle has come off the
main brake line, it can be steered and
landed with the rear risers. Be aware
that, when rear riser steering, the
glider is a great deal more responsive
to pilot input, and the stall happens
very suddenly.
Further references
Rain-induced deep stall
There are two reasons why flying with
a wet wing increases the risk of deep
stalling:
First reason: A paraglider flying in
heavy rain will soon grow significantly
heavier and thereby undergo changes
in the centre of gravity and the angle of
incidence. This may lead to deep
stalls. Note that older wings will absorb
more water than newer ones due to
the coating on older wings being more
permeable – this means that the
critical mass may be reached sooner
on older wings.
Second reason has to do with the
actual rain drops on the top surface – if
enough large rain drops form that the
entire top surface is covered, but they
don’t join together to either flow off or
become a homogeneous mass, the
surface may become so rugged that
the airflow separates and the wing
stalls.
This phenomenon has been observed
on hang-gliders and gliders for years
but only recently have we discovered
that paragliders may also be affected.
It is more likely to happen with new
wings where the cloth is still highly
hydrophobic and the drops thus do not
penetrate but remain on the surface.
We know from computer simulations
and practical tests that this is
physically possible but we also
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