B stall – Windtech kali User Manual
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with the wind, and it is very easy to become disorientated.
This manoeuvre is not approved for bank angles higher than 60 º. At this upper limit the
sink rate of the canopy is approximately 10 m/s and the overload is equal to 2G's.
For bank angles higher than 60 degrees the sink rate can achieve 20 m/s but the greater
overload (High gravitational forces - G's) can cause eyesight and equilibrium problems,
and cause some people to 'black out' (faint), which consequently can make the manoeu-
vre extremely dangerous.
To recover from a spiral dive, the inner brake must be progressively and slowly released,
until the canopy assumes normal flight, and angle of bank, again. A good rule of thumb
is to use the same number of 360-degree turns as you did on entry on exit to give a safe
and progressive pullout. If you release hands up from a tight spiral dive you will experi-
ence a big surge followed by a dive. (In turbulent air this can result in a collapse.) The
K A L I
has been tested for this but it is advisable to learn the correct exit method, i.e.
progressively release the inside brake.
> b stall
The B-line stall is a real stall even though the wing appears to be flying above your head
the laminar airflow over the wing is completely lost. During B-Stall, the canopy falls per-
pendicularly to the ground (straight down, but drifting with the wind) at a sink rate of 5
to 12 m/s, with an angle of attack of 90 degrees.
To enter a B-Stall, it is necessary to sit upright in your harness, reach up with the brakes
still in your hands (preferably with the toggles around your wrists)
&
securely clutch each
B risers in each hand at the top near the Maillons Rapides (quick links). To enter the B-
line stall, pull down symmetrically on the B risers. (About 40 cm)
The force initially is quite hard (up to about 15cm) but for the last part the force required
to pull down is less. Keep your weight centred in the harness, and keep the risers held at
a symmetric level to each other. The more B riser pulled the faster the decent rate, but
the glider can become unstable with a very deep B-line.
To return the glider to normal flight conditions:
Ease up the B-risers SYMMETRICALLY for 50% (25-cm of B-line still held) holding some
pressure, then symmetrically completely and rapidly release them. If necessary, control
the surging forward of the canopy by gently braking when the glider is in front of you.
What you are trying to achieve is to not shock-load the glider by an immediate release
from a deep B-line, whilst at the time not easing off too slowly and risking a deep stall
in turbulent conditions. Releasing the B-lines from a deep B-line position works fine (
&
if unsure whilst attempting the manoeuvre simply release the B-lines together from this
position) but puts unnecessary load on the glider.
If necessary, control the surging forward of the canopy by gently braking when the glid-
er is in front of you. Do not brake too hard as you may cause the wing to enter a full stall
in this way, and let the brakes back up as soon as the surge has stopped.