Rapid Descents - Advance Sigma 7 Betriebshandbuch

Basically, after a side collapse, fl ight direction must be held by care-
fully applied opposite brake, and then pumping used on the closed
side to raise its internal air pressure. This will speed up wing reopen-
ing. Steering inputs on the open (other) wing must be done carefully,
so as not to stall it.
Poorly fl own wingovers can cause a wingtip to fold inwards from the
side, causing it to catch in the lines and create a cravat. Due to the
high drag they produce cravats can lead to strong rotation (spiralling).
Stop an increase in rotation rate by just the right amount of outside
brake. Then open the cravatted wingtip by pulling the orange stabilo
line. Clearing a cravat can be also done by 'pumping'. The appropri-
ate brake should be applied to 75% brake travel within two seconds,
and then released immediately.
Symmetrical collapse (Front stall)
Following a spontaneous or deliberate front collapse the airfl ow will
break away from the wing which will pitch back, followed by the pilot.
The glider will start to fl y again shortly afterwards. After a large front
collapse it could be that the wingtips do not completely reopen. Ex-
cessive brake should not be used to force the wingtips open, as the-
re is then a risk of completely stalling the airfl ow.
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Rapid descents

For a quick and effi cient way of getting down the ADVANCE test team
recommend big ears (with or without speed bar) or the spiral dive –
the choice depends on the situation.
Tip: Practise rapid descents now and then in quiet conditions
– so it won't become an emergency when you need it.
Symmetrical collapsing of the wingtips (Big ears)
To apply big ears take each outer red marked A-line and pull both
down fi rmly at the same time. This will fold in the wingtips which will
stay in this position. To open them again let the A-lines go and, if ne-
cessary, help open them with a brief pull on the brakes.
The sink rate can be increased by applying speed bar. Depending on
the situation the glider can be steered using weight shift,.
Caution: Do not fl y spirals or aggressive changes of direction
while fl ying with big ears: the increased wing loading carried
by fewer lines can damage the glider.
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04.06.2008 14:27:51 Uhr 04.06.2008 14:27:51 Uhr