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Even if the canopy is wet or the air temperature is very low, the tendency to stall increases.
Flying in the rain should be avoided as far as possible, as the raindrops on the canopy increase the Vmin and thus the
tendency to stall increases. Also very low temperatures can be problematic. In both cases, especially when the
brakes are applied and/or the line geometry is no longer trimmed correctly.
If the glider is in a deep stall, you can recognize this by the fact that the noise is very low and the glider is in an unusual
position above the pilot. In this case it is absolutely necessary to release the steering lines!
If the canopy and lines are in good condition, the Airtaxi² will automatically pick up speed again within 2 to 3 seconds.
If, for whatever reason, this is not the case, the A-risers must be pushed forward or the acceleration system must be
activated.
If a glider has been in a continuous stall for no apparent reason (e.g. wet glider, flight in rain or inadmissible take-off
weight), it must be checked before the next flight.
Attention: The brakes must not be applied in deep stall flight, as the paraglider immediately enters the full stall. A
stable stall may no longer be released near the ground due to a possible pendulum movement. Instead, the pilot
prepares himself for a hard landing, if possible with a landing fall.
12.5. Full stall
To initiate a full stall, both brake lines must be pulled through completely. When the stall speed is reached, the canopy
empties abruptly and suddenly tilts backwards.
It is very important, despite the unpleasant reaction of the glider in a full stall, to keep the steering lines pulled through
until the empty glider comes back over the pilot (approx. 3 to 6 seconds) and stabilizes in this position.
Only now the steering lines are reasonably fast (switching time >=2 sec) and symmetrically released. The optimal
recovery should take place in 2 phases: 1. prefilling of the canopy (slow release of the brakes up to shoulder height)
until the canopy is fully open again; 2. recovery (braking to 0%).
If the canopy is released too quickly or asymmetrically, the result may be a large collapse or front stall.
Attention: A wrong, too early, asymmetrical or too fast released full stall can result in an extremely wide forward
movement of the canopy! In extreme cases under the pilot!
12.6. Spin
By stalling one side, the flow can break off at half of the wing. This reverses the direction of air flow. The trailing edge,
which is deeply braked, is then streamed from the back and flies in the opposite direction and the canopy rotates
around its vertical axis.
There are 2 causes for a spin:
- A brake line is pulled through too quickly and too far (example: initiating a spiral dive).
- in slow flight one side is braked too much (example: in thermal circling)
If an inadvertently initiated negative turn is immediately released, the glider returns to normal flight without great loss
of altitude. If the negative turn is held longer, the glider can accelerate and shoot forward on one side. This can result
in an impulsive collapse or entanglement.
12.7. Wingover
Tight turns to the left and right are flown alternately. The cross slope is progressively increased. If the dynamics and
lateral position of this flight manoeuvre is too high, the outer wing can relieve the load. If the lateral inclination is
further increased and the reaction is wrong, the result may be an impulsive, large-scale collapse.
Full stall, spin and wingover on all paragliders can have life-threatening consequences!!
12.8. Emergency steering
If the steering lines fail, the "Airtaxi²" can easily be steered by using the rear risers. The distance to the stall is of
course much shorter when steering with the rear risers than with the steering lines, it is about 10 - 15 cm with the
"Airtaxi²". You can also fly light curves by pulling the Stabilo lines or by weight shifting.
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13. Decent aids
13.1. Spiral dive
The spiral dive is the most efficient way to descend fast. However, high loads occur for material and pilot.
It has to be taken into consideration that, depending on the daily shape, the outside temperature (cold!) and the sink
rate, you may sooner or later lose consciousness. Many pilots slow down their breathing during the spiral or go over
to press breathing, which increases the risk of losing control even more. At the first signs of dizziness, loss of
consciousness and loss of vision, the spiral must be immediately stopped.
The spiral dive is initiated by carefully pulling the brake line on one side and shifting the weight to the inside of the
curve. Due to the direct handling the Airtaxi² quickly takes a high lateral inclination and flies a steep turn. As soon as
the wing comes in front of the pilot ( goes on the nose ) an impulse is generated, which the pilot should follow by
shifting his weight to the outside of the curve.
The sink rate and inclination in the spiral dive are increased by a controlled pulling of the brake line inside the curve.
Slight braking on the outside of the curve prevents the outer wingtip from collapsing.
To exit the spiral dive, the brake inside the curve is slowly released.
Rapid release of the brake means that the high airspeed (up to over 100 km/h) is translated in a strong pendulum
movement into height. The result is an extreme deceleration at the end of the pendulum movement with subsequent
tilting of the canopy. You also have to calculate that you will get into your own wake vortex (rotor)!
Due to the extreme loss of height in the spiral dive, it is always important to ensure sufficient safety height!
Attention:
Almost every paraglider reaches a sink rate at which the canopy faces the openings downwards ("goes
up on the nose!") and remains in this position despite releasing the steering lines and continues to spiral (stable spiral
dive).
The Airtaxi² has been classified B according to EN 926-2:2013. Due to unfavourable influences, however, the
reactions can also be more demanding than described in this classification. The causes in such a case can be
complex. For example: harness geometry (suspension height), cross straps, turbulent air, holding on to the riser,
shifting the pilot's weight to the inside of the curve and similar.
If, against all expectations, a stable spiral dive should occur, this is released by shifting the pilot's weight to the outside
of the curve and counter-braking in a controlled manner.
Attention:
in a stable spiral dive, extreme G loads can have an effect on the body and require a lot of physical
strength!
13.2. Big Ears
The so called "big ears" manoever is an easy, but not very effective descent method where the forward speed is
higher than the descent speed. It is more suitable to reduce the glide angle and to gain horizontal distance from a
source of danger than to descend fast.
To perform "big ears", the two wingtips are folded symmetrically downwards by pulling the outer A-risers (A').
The "big ears" can increase the descent speed to approx. 5 m/sec. and reduce the glide angle.
By using the foot accelerator the sink rate and the forward speed can be increased significantly.
It is sufficient to release the outer A-risers to exit this manoever. The wing tips of the Airtaxi² usually opens
automatically. The pilot can slightly brake to speed up the opening.
Attention: Never fly a spiral dive with big ears, because the middle A-lines are loaded beyond their limits.
13.3. B-Stall
The B-stall is easy to enter with the Airtaxi². The B-risers are slowly and symmetrically pulled down to 20 cm. The
airflow stops and the glider descends vertically.
To exit the manoever it is sufficient to raise the B-risers again in a time of approx. 1 second.
