Advance SIGMA 4 Manuel D'utilisation page 36

Flying with the speed system:
polar curve. This gives very good glide performance at high speeds.
Remember though that the accelerated glider is more unstable. Collapses
during accelerated flight occur with more energy and impulse.
When flying through turbulent air with the speed bar on,
first release the speed bar then apply the required amount of
brake to keep the glider under control. In order to get the
most out of the speed system whilst flying in rough air we
suggest that you fly actively with the speed bar. This means
pushing on more speed when the glider has a high angle of
attack and releasing when the glider starts to overshoot. This will also
reduce the tendency for the glider to yaw.
Symmetrical or assymmetrical collapses:
highly satisfying solid feel. An active flying style will virtually eliminate
collapses. Larger collapses (over 50%) are characterised by a reasonably
dynamic turn which is easily controlled. For these situations we
recommend the following:
Weight shift to the open side. Try to rotate with any ensuing turn so as
to reduce the potential for a twist. This also maintains airspeed and
internal pressure promoting a fast re-opening. Depending on the
severity of the turn apply brake on the open side so as to not enter a
spiral dive but be aware of creating a potential stall. The object is to fly
the glider in a desirable direction (avoiding obstacles) and then re-open
the collapsed side using a generous pumping action.
Fast descents:
recommends, depending on the situation, a spiral dive or big ears. It is
a good idea that you practise these in smooth air. Even flares and
landings with big ears should be practised in smooth conditions so that
a serious scenario doesn't turn into a emergency.
Spiral Dive:
on one side. The desired bank angle is controlled by the amount of brake
applied. This can be supported by weight shifting. At the same time the
pilots head and field of view should be oriented in the direction of the
turn. To exit the spiral raise the inside brake gradually. Depending on
the steepness of the spiral it is possible that the glider could do another
rotation even after releasing the brake.
the application of big ears is as for other gliders via the
Big Ears:
symmetrical pulling down of the outer one or two A lines. We suggest
you use both outer A lines so as to not reduce forward speed despite
36
to quickly lose height the
the spiral dive is entered into by gradually applying brake
the has an exceptionally flat
SIGMA 4
the
SIGMA 4
ADVANCE
conveys a
test team