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Version 1.0 March 2017
B-Line Stall
This is a fast descent method and is a useful emergency procedure. With both hands through the brake handles, the
pilot takes hold of the tops of the B-risers, one in each hand, and pulls them down by around 50 cm. This will stall the
canopy and forward speed will drop to zero. Make sure you have plenty of ground clearance because the descent
rate can be over 10 m/sec. To increase the descent rate pull harder on the B-risers. When you release the B-risers the
canopy will automatically start flying again, normally within two seconds. Sometimes the canopy will turn gently when
it exits from the B-line stall. It is normally better to release the B-riser fairly quickly, as doing so slowly may result in
the canopy entering deep stall.
Always release the risers symmetrically, as an asymmetric release from a B-line stall may result in the glider entering a
spin. This manoeuvre is useful when you need to lose a lot of height quickly, perhaps when escaping from a
thunderstorm. It should not be performed with less than 100 m of ground clearance (see also Chapter 5).
Spiral Dive
A normal turn can be converted into a strong spiral dive by continuing to apply one brake. The bank angle and speed
of the turn will increase as the downward spiral is continued. Be careful to enter the spiral gradually as too quick a
brake application can cause a spin or cause you to enter an over-the-nose spiral.
BGD gliders are designed and tested to recover from normal spirals with a descent rate inferior to 16 m/s,
automatically without pilot input. If the pilot increases the descent rate of the spiral to over 16 m/s or initiates what is
known as an over-the-nose spiral, the glider may require pilot input to recover. In this case all the pilot needs to do is
to apply some outside brake and steer the glider out of the turn.
The over-the-nose spiral is an extreme type of spiral dive where the glider points almost directly at the ground. You
can enter it by making a sudden brake application during the spiral entry so that the glider yaws around and the nose
ends up pointing at the ground. At this point the glider picks up speed very quickly. This technique is very similar to
4 Flight Characteristics