Stalls - Nova IBEX-4 Handbuch

_60
Such a collapse normally only affects a small part of the whole span
and the wing will not react significantly. During larger collapses which
affect 50 percent or more of the span, the wing will clearly react: due
to the increased drag of the collapsed side, the glider will begin to turn
towards that side. Simultaneously the wing will pitch forward because
of the reduced area carrying the wing loading, i.e. because this causes
that side of the wing to accelerate.
!
The pilot can prevent this turn and forward pitch by braking the un-
collapsed side of the wing. Braking the uncollapsed side is essential,
If the open side is especially near the ground. This manoeuvre should be practised with
braked too much the
induced collapsed at height, preferably during an SIV/pilotage course.
glider may spin – see
the section on spins.
Frontal collapse
A frontal collapse is also a consequence of turbulence. Unlike an
asymmetric collapse, during a frontal collapse the whole leading edge
folds downwards.
All our paragliders open automatically after frontal, as well as asym-
metric collapses (as stipulated in the certification standards). To speed
up the re-inflation of the leading edge after a frontal collapse, we
recommend a very short stab of both brakes. It is important to then
release both brakes completely.

Stalls

Spin
If the pilot brakes one side of the glider too much, a spin will result.
In a conventional turn, the axis of rotation is remote from the wing.
When a wing spins, the axis of rotation moves within the wing span.
The over-braked side of the wing slides back.
The correct pilot reaction is to immediately release both brakes. Occa-
sionally it is necessary to stop the canopy pitching forward.
Full stall
If both brakes are symmetrically pulled too far, a full stall will result. This
means that the wing loses its forward momentum, whilst the pilot con-
tinues to travel forwards. From the pilot's perspective it feels like the
wing falls backwards. At this moment it is essential that the brakes are
not fully released as there is a risk that the wing will dive – potentially
underneath the pilot.
The available brake travel up to the stall point depends on the size of
the wing:
• 61 cm for the IBEX 4 XXS
• 66 cm for the IBEX 4 S
These figures give a rough indication. Their inclusion in this manual is
required by EN 926. In turbulent air, a stall may occur markedly sooner
or later than these figures indicate. Therefore these figures only have
limited significance.
Parachutal/deep stall
A parachutal or deep stall is defined as flight without forward
momentum and with a large sink rate. All our paragliders automatically
recover from a parachutal stall so long as the brakes are released, the
wing is in an airworthy condition and the pilot flies within the operating
limits of the glider.
If the wing is porous or its lines have been altered to the extent that it
is no longer airworthy, then the risk of deep stall is increased. A wet or
icy canopy also carries an increased risk of deep stall.
If a danger situation occurs (for example, unexpected rain) then any
manoeuvre with a high angle of attack should be strictly avoided. This
includes big ears (without speed bar), B-line stall as well as using a
lot of brake. If the flying conditions permit, using a little speed bar is
advisable.
In the case of a deep stall, the speed bar should be utilised. The wing
should then return to normal flight. If this is not the case, we recom-
mend pushing the A-risers forward.
Alternatively, it is possible to recover from a deep stall with a quick,
symmetrical tug on the brakes which allows the canopy to pitch back-
wards. The subsequent forward pitching returns the wing to normal flight.
_61 _EN
!
A full stall is a com-
plex manoeuvre and
an explanation of its
correct execution is
• 63 cm for the IBEX 4 XS
beyond the scope of
this manual. Anyone
• 68 cm for the IBEX 4 M
wishing to learn this
manoeuvre should
undertake an SIV/
pilotage course.
!
Please note: if the
brakes are pulled for
longer than a quick
tug, the wing will go
into a full stall!