Advance sigma 6 Manuel D'utilisation page 23

accelerate and guide the risers until the canopy is above the head,
without either pulling down or pushing the risers exessively forward.
The canopy rises progressively without any «hard point». The canopy
will cease to rise if not guided by the risers.
The canopy of the SIGMA 6 inflates quickly and lifts evenly without
catching or overshooting. In more difficult launch conditions, cross-
winds for example, the glider's tendency to go off at an angle during
the inflation phase can be prevented with a more determined initial
run and confident, swift inflation.
Normal flight
The SIGMA 6 achieves «best glide» with brakes in the hands up posi-
tion. Lightly applying brakes will reduce the sink rate. When flying
through turbulence the application of a small amount of brake will
increase stability.
There are three different basic brake settings:
- No braking for best gliding (without using the control lines and
consequent braking effect)
- Gentle braking for the best sink rate (rule of thumb: the glider
has a crease, visible in front of the trailing edge on the lower
surface)
- Moderate braking for best stability (rule of thumb: the glider has
two creases in the lower surface - visible in front of the trailing
edge on the lower surface)
When flying in bumpy conditions the ADVANCE test team recommends
using the basic position for the best sink rate. Continue to use the play
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up to the position for best stability with the goal of controlling the pit-
ching motion in the direction of flight and reducing it to a minimum
(the glider always remains above the pilot in the optimum position).
The SIGMA 6 has precise brake and control travel. Its balanced hand-
ling and the response to steering commands are a successful com-
promise between effort and glider control. The SIGMA 6 behaves in a
well-mannered way in response to exaggerated steering inputs when
thermalling. However, it is important to remember to maintain the
minimum speed when top landing or when making the final appro-
ach. Falling short of this will provoke a symmetric stall.
Turns
The SIGMA 6 possesses very comfortable brake pressure. It will re-
spond to brake application in an immediate and proportional manner
to the amount of brake applied.
To get used to it's turning characteristics, make first turns gradually
and progressively. To make the most efficient turns in thermal condi-
tions, find the core of the thermal and control the radius of your cir-
cle with the outside brake, giving you more speed.
Flying with the speed system
The SIGMA 6 has an exceptionally flat 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 tur-
bulent air with the speed bar on, first release the speed bar then ap-
ply the required amount of brake to keep the glider under control.
Accelerated flight
The SIGMA 6 has a line and wing construction that is designed to re-
duce air resistance. This enables a very good gliding performance
and minimal falling off of the polar curve even in the high speed ran-
ge. Take care not to apply the brake at the same time to the accele-
rated glider, otherwise you will immediately eliminate the accumula-
ted energy and gliding speed of your wing.
We recommend that you use the following basic settings to achieve
«real air» best glide :
- at 10 km/hr headwind, approx. 15 % acceleration
- at 20 km/hr headwind, approx. 50 % acceleration
- with no wind, do not brake at all
- with a tailwind, gently brake the glider to fly with the best sink rate
Remember that an accelerated wing becomes less stable. Collapses
in the accelerated mode become more unpredictable on account of
the magnified force effects.
When you fly into turbulent air in accelerated mode, first take the
entire pressure off the accelerator (reduce to trim speed) and then
give the necessary steering inputs in order to be able to control the
wing. If you want to achieve maximum performance in turbulent air
while in accelerated flight, this calls for an active flying style with the
accelerator. Like active flying with the control lines, this means ...
- with an increasing angle of attack e.g. in an up-current,
you press your accelerator harder
- with a decreasing angle of attack, when the wing pulls forwards,
release the accelerator.
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In this way the pitching motion in the direction of flight is reduced to
a minimum, and the optimum gliding performance is achieved.
Negative Spin (Asymmetric or one-sided stall)
When re-centering a thermal the SIGMA 6 will provide early and cle-
ar feedback regarding the onset of a stall by the feeling of quickly in-
creasing brake pressure. If you disregard this feedback and continue
to pull on the brake to the stall point you will feel a sudden reduction
in brake line pressure. The glider will resume normal flight immedi-
ately once the brake is released. If you fail to react at this point and
coax the the SIGMA 6 into a spin, it will react like a dynamic DHV 2
class glider. That means that depending on the entry situation, very
extreme reactions are possible (over shooting with increased likeli-
hood of frontal collapse and cravatte's). A regular pilot can dampen
and stabilise the glider during the overshooting phase with correctly
timed inputs. Thus normal flight can be resumed without additional
collapses.
Asymmetrical collapses
The SIGMA 6 conveys a 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 easy to con-
trol. For these more extreme situations we recommend the following
pilot reactions:
If you are clear of obstacles its best to allow the glider to initially turn
at the early stage of the recovery whilst assessing the situation. Use
your body weight to transfer the load to the inflated wing side and
control the turn rate using the brake. The energy of the turn (or roll)
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