MAC PARA ARAVIS Series, Руководство пользователя, Страница: 20 / 36

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Symmetric collapse (Front stall)
A negative angle of attack can also cause central part or all of the leading edge of the
glider to collapse. Symmetric (frontal) collapses will normally re-open without pilot input.
The paraglider will pitch forward and then regain speed. Assist this process if necessary
with a symmetric application of the brakes. Take care not to apply too much brake for too
long as this may stall the wing.
In the case of extreme front stalls across the entire wing chord, the wing tips may move
forward making the glider form a U-shape. Again, recovery is by light symmetrical braking
on both sides. Take care that both wingtips return to normal flight evenly.
If you get a collapse while in accelerated flight, release the speed bar immediately. Then
apply the normal procedure for unaccelerated asymmetric collapse.
Attention! As already described the Aravis is a paraglider with shark nose aerofoils and
with more backwards positioned A-suspension points. These aerofoils and position of A-
suspension points give more inherent stability and offers more resistance against collapse.
It wasn`t necessary to feature the Aravis with special folding lines to perform the
manoeuver. But nevertheless the accelerated symmetric collapse must be performed
correctly in a proper way and this preferably by safety trainings. It is important to take the
two outermost A-lines together (approx. 10cm above the quick links) firmly in your hands.
Do not use the central A-lines! At the beginning of pulling the move (in the direction of
pilot`s body) must be slow and after the move of approx. 5 cm, it can only be strongly
pulled down. By this way the leading edge collapse properly over its span. In case you use
all A-risers for this manoeuvre and you do it without initial pulling it may happen that the
leading edge collapses over all depth in the centre of the wing. The result may be an
asymmetric opening and the risk of a big cravat increases!
Parachutal stall (deep stall)
Paragliders can go into a deep stall for some reasons: brake lines too short (no slack),
altered trim/line length and changes to profile characteristics caused by moisture (e.g.
flying in rain). Paragliders have a particular tendency to stall if the wing-loading is too low.
An out-of-trim glider, caused by changes in line lengths due to prolonged use, may also
have a higher deep stall tendency.
In a deep stall, the airflow from the front reduces and the glider goes into a stable flight
attitude without forward momentum. The paraglider sinks almost vertically at 4-5 m/s and
there is noticeably less flight noise.
The Aravis has no tendency to get into a deep stall. Should this nevertheless occur, make
sure your brakes are fully released, the glider will then normally recover on its own
immediately. If the glider still doesn’t recover either put your hands on the A risers and
push forward or use the speed bar to accelerate to get the wing into a normal flying
position. After you have landed, the glider and the length of the lines must be checked.