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Section 7
Dangerous Situations and Extreme Flying
Types of stall
When a paraglider flies through the air, a
laminar and turbulent boundary layer is
created. Extremely dangerous flight
configurations can result if the laminar
boundary layer is interrupted, with practically
the entire airflow along the top surface
braking away. This happens in particular
when the angle of attack is too great.
There are three different types of stall in
paragliding.
Deep stall
Paragliders can go into a deep stall for a
variety of reasons: brake lines too short (no
slack), old or damaged glider material which
therefore has increased level of permeability,
altered trim/line length and changes to
profile characteristics caused by moisture
(e.g. flying in rain). Paragliders have a
particular tendency to stall if the wing-
loading is too low.
In a deep stall, the airflow from the front
reduces and the glider goes into a stable
flight attitude without forward momentum.
The paraglider sinks almost vertically at 4-
5m/s and there is noticeably less flight noise.
Recovery
Remain in an upright position and push the
A- and B-risers in the direction you are
flying, so as to shorten them by 5-10cm.
If you have a speed system, you can also
use it to accelerate, so that the glider goes
into a normal flying position from the deep
stall.
After you have landed, the glider and the
length of the lines must be checked.
Full stall
With a full stall, the lift-generating airflow
over the glider breaks away completely or
nearly completely.
It is triggered when the maximum possible
angle of attack is exceeded. The most
common cause is going below the minimum
speed or flying near the minimum speed
combined with the effects of turbulence.
In full stall, the paraglider loses its forwards
travel, surges backwards and deflates. If the
brakes are held down, the canopy comes up
over the pilot again. The result is an almost
vertical descent with a sink rate of approx.
8m/s.
Recovery
Fully release the brakes within 3 seconds
(count 21, 22, 23). If the brakes are released
too slowly, the paraglider may spin. The spin
stops automatically when the brakes are
released completely.
WARNING
Full stall and spin are manoeuvres which
can be fatal if recovery is not correct.
These manoeuvres should therefore be
avoided. However, it is important to learn
how to recognise the indications that a
glider is about to stall so that you can take
immediate action to prevent it.
WARNING
If the canopy has gone back during a full
stall, the brakes must be held down,
otherwise the canopy may surge forward
and, in an extreme case, end up
underneath the pilot. Hold the brakes
down until the canopy is above you again.
Summary of Contents for Powerplay Sting 2
Page 1: ...Version 1 0 Date 08 08 2014 Instruction Manual EN ...
Page 55: ...Notes ...
