Advance acoustic BIBETA 6, Руководство пользователя

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Spiral dive
Enter the spiral with a progressive increase of brake application . Head
and vision should be directed in the direction of turn . As the bank in-
creases so does the rotation rate and the centrifugal force .
Basically the behaviour of the glider can be divided into two phases: in
the first the glider increases its angle of bank and turns in ever decrea-
sing circles . At the second phase the glider bites into the spiral: this
means that the wing dives forward relative to the pilot and appears
to be aligned with the horizon – the airspeed, g and rate of rotation
increase markedly . During the spiral try to maintain the neutral sitting
position and don’t fight the centrifugal force – your body will be pulled
outwards .
Recovery requires a progressive releasing of the brake on the inside
of the turn . From a spiral dive with high sink and rotation rates it is
essential to carefully apply some inside brake again while recovery is
taking place, in order to slow down the natural recovery behaviour and
subsequent high energy climb . This is the only way to avoid an exces-
sive pitch up attitude and consequent surge . Make sure you recover
with enough height above the ground . Generally one should expect the
recovery to take the same amount of time as the entry, but the rate of
descent during recovery will be higher!
The BIBETA 6 comes out of the spiral by itself if a neutral sitting posi-
tion is maintained . Active weight shift to the inside of the turn can lead
to greater acceleration and a delayed natural recovery .
Caution: Do not fly spiral dives with big ears; the raised wing
loading on a reduced wing area together with the reduction of
effective lines can seriously overstress and damage your glider .
Caution: To avoid a collapse enter the spiral carefully when in
accelerated flight, because the angle of attack is reduced .
Caution: Remember that you, the pilot, may be familiar with the
high g-loading in a spiral dive, but it might upset your passenger
a lot . If a descent is required for passenger wellbeing we recom-
mend the Vary-Grip big ears configuration together with a speed
increase using the trim system .
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