Windtech kinetik plus - Manual (Page 16)

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also wing loading) the glider will accelerate into the spiral, especially if one aids this with
weight-shift. Once the turn has converted into a spiral dive the pilot can control the
speed of rotation and descent with small changes of interior and exterior brake, and
more or less weight shift. It is possible to achieve descent rates of 10-15m/s or more in
this manoeuvre.
It is dangerous to induce spiral dives close to the ground due to the extreme centrifugal
forces which can cause fainting and, in some cases, blackouts or blurred vision..If you are
at all susceptible to any of these conditions, or are feeling at all unwell for any reason,
then you should not induce a spiral dive for this reason.
The exit from this manoeuvre should be performed gradually and progressively, finishing
in a nice controlled gentle turn to re-stabilise the wing. To do this, the pilot has to grad-
ually ease off the inside brake, and reduce weight shift, then gently apply a little outside
brake to ease the glider out of the spiral.
The pilot must be very careful not to exit a spiral (especially if well developed) too briskly,
as this could result in a steep climb out (with the wing far behind the pilot and in a very
vulnerable position, with little internal pressure, no airspeed and prone to collapses) fol-
lowed by a sharp dive which may need damping to prevent a collapse.
It is NOT recommended to induce a spiral dive at the same time as applying any thrust
or power from the engine, as this could result in instability.
-- b-line stall
To induce a ‘B-line” stall, first take hold of both ‘B’ risers (left and right) one in each hand
(left and right respectively) FIRMLY at the maillons. Then, pull the B-risers down togeth-
er to approximately the level of the karabiners, BEING VERY CAREFUL TO DO THIS SYM-
METRICALLY so as to not induce a spin.
This will “B-stall” the glider, by deforming the aerofoil section of the wing in such a way
as to stop the airflow going over it as normal, effectively ‘breaking’ the aerofoil effect. If
done correctly, the glider will now enter into a “B-line stall”, which is a kind of “para-
chutal” stall, stopping the glider flying and rendering one’s trajectory effectively straight
down through the air (BUT DRIFTING WITH THE WIND).
Once in the “B-line” stall one can control the descent rate to a degree by pulling down
more or less on the B-risers and it is possible (in still air) to achieve descent rates from
5-11 m/s. BE CAREFUL, AS PULLING DOWN TOO FAR ON THE B-LINES CAN CAUSE THE
GLIDER TO BECOME UNSTABLE, SO THIS SHOULD BE AVOIDED.
To exit from the B-line stall correctly, and minimise the chance of any instability, the
pilot should keep a firm hold of the B-risers and raise them until there remains 10cm of
travel of the B-risers and then release them completely, taking care to do this SIMULTA-
NEOUSLY.
If the B-line is entered, or released, asymmetrically, it is possible to enter a spin, and so