Fergus, whilst I agree with what you say, with the wing drop we are talking
about the incipient stage of a spin, ie: before it has fully developed - in
the fully developed spin I agree wholeheartedly the rotation must be
stopped with rudder before unstalling the main plane.
At the incipeint stage the amount of yaw may be negligable. Rapidly moving
the stick forward reduces the angle of attack and the aircraft is now
flying again at which point aelieron can be used to roll level, and full
power applied to climb away. This was the method I was taught on my
instructor course, and was reconfirmed on a recent standardisation course,
with an RAF instructor instructor.
The rationale being that this is the quickest way to return to a safe flight
condition near to the ground. The inadvertent entry into the incipent stage
of a spin being most likely on the turn from base to final in the circuit (
pattern) We have found a real risk of students "picking up" a dropped wing
with rudder entering a spin in the opposite direction
BTW, a wing does not necesarily have to be "speeded up" to recover, mearly
unloading it will have the same effect.
For exaple a CAP 10 I fly aero's in has a wing level, unaccelerated stall
speed of 55 Kts. I can have that wing still flying at 30 kts ( at the top
of a loop for example at about 1/2 a G.
Equally I can stall it at 120 kts pulling out too sharply at the bottom at
2.5 - 3 G
Finally, whilst this discussion is healthy, I'm sure you will agree that
reading about it is no substitute for a session with an instructor or coach
in an aircraft.
Dave
.
On 06/09/2008, Fergus Kyle <VE3LVO@rac.ca> wrote:
>
> David,
> You mentioned:
> >" I got a bit lazy once, had the ball out to the left, and sure enough I
> had a wing drop
> >(about 80deg in about half a second )- in other words the incipient stage
> of a spin.
> >
> >Standard recovery worked well, (as a reminder:- stick forward to break the
> >stall, **smoothly up to full power, roll wings level.) lost about 300 ft.
> and
> >the aircraft recovered immaculately. Please also remember the "stall
> speed"
> >is only wing level and unaccellerated stall speed. Wings actually stall
> due
> >to the angle of attack ! OK review over - for which I appologise."
>
> There will (or have been) others to note this, [Svein and Carl for
> instance]but I
> have flown maybe 56 various aircraft, mostly advanced, and in stall
> recovery
> (or spin
> prevention) none of those ever used the word 'roll' until having used
> 'rudder' (yaw).
> The only time I can remember the roll word was about number 52 in tumbling
> a
> T33
> and it said don't touch a damn thing until you find out what it settles
> into
> - and then it
> said Rudder First.*
> Angle of attack as cause of stall is correct as far as it goes, but
> wing drop is
> an indication of the slower wing - and only yaw speeds up that wing - with
> rudder.
> That's why I suspected "wind-wag" or "tail-wag" instructions at Oshkosh as
> a
>
> possible cause of the low-level stall and spin we all regret.
> I only write this because impressions are easy to instill when tyros
> read this
> column and I'm sure you meant it to come out differently.
> Cheers, Ferg
> * Admittedly one of them said "....in a tumble, try everything till you
> find
> the one that
> works, otherwise eject at 13,000 AGL because you are already below 9,000
> [lag]."
> ** I think "recover from dive with engine idle" comes next......
>
> .
>
>
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