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noblues
25th May 2009, 07:52
Whats the general opinion on Incipient Spin Recovery technique?

Do you pick up the wing with rudder, or leave it to drop and use standard stall recovery picking it up with aileron once unstalled?

kwachon
25th May 2009, 08:12
Intentional spin entry should have a clean stall, which in most types is achieved by reducing airspeed and maintaining a nose up attitude of at least 14 degrees. At lower nose attitudes the stall will be less pronounced and the aircraft may need to be forced into the spin
.
As the aircraft enters the stall the nose will drop, at which point full back stick and full rudder should be applied in the intended direction of the spin. Typically the aircraft will assume a nose low attitude, as the incipient phase is passed and the spin fully develops. Throughout the spin full back stick with aileron neutral must be held (some specific types may also need aileron), to maintain the wings in a stalled condition.

The horizon will be moving in the direction opposite to the direction of the spin, and it is important to be aware of this, particularly where the entry is inadvertent and hence not planned. The direction of the spin is of critical importance in determining the required input to recover the spin.
Recovery is initiated by applying rudder opposite to the direction of the spin, to slow and eventually arrest the rotation. When the yaw rate has dropped or stopped, backpressure should be eased off to unstall the wing, while neutralising the rudder. As the wing unstalls the aircraft will typically assume a near vertical nose down attitude, and speed will rapidly build up if this attitude is maintained. Therefore it is necessary to pull out of the dive, and it is important to apply the right amount of backpressure to prevent the wing from stalling again, but also to ensure that Vne is not reached during the recovery. Once the elevator is applied to the recovery, power can be applied to enhance the effectiveness of the tail controls and effect lesser height loss.

KW:ok:

18greens
25th May 2009, 08:28
I guess the first thing to say is check the poh. Beyond that ...

If the spin is still in the incipient stage the recovery technique in most ac is simply to centralise the controls regardless of attitude. No need to pick up the wing. It will stop rotation and you then need to recover which usually involves rolling using aileron to the nearest horizon and pull out of the dive.

Only once it has gone beyond the incipient stage do you check direction, apply full opposite rudder and move the cc centrally forward until the aircraft stops rotation then centralise rudder and recover from the impressive dive.

If you are not sure get someone to show you.

DB6
25th May 2009, 09:12
Incipient spin recognition: heavy buffet, undemanded roll
Incipient spin recovery: centralise controls, wait for rotation to stop, recover from resulting (probably unusual) attitude. If rotation doesn't stop use full spin recovery technique.
It is important to realise that it is a stalled condition with yaw - therefore stalling one wing more that the other, causing roll - is what is causing the incipient spin. So it's reducing the angle of attack which is important, not removing the yaw. Opposite rudder at the incipient stage will just cause a reversal of the roll unless you reduce the AoA. So of your options it is No. 2.
As far as I know this (centralising controls) works for all normallly configured aircraft, full spin recovery is different and type-specific.

BEagle
25th May 2009, 15:58
What he said!

'Picking up the wing' - may well make things worse. Even a lot worse.

Just centralise and enjoy the ride, then recover from the resulting descent.

ShyTorque
25th May 2009, 20:05
then recover from the resulting descent.

Yes, far less scary than saying "ease out of the dive" ;)

hugh flung_dung
26th May 2009, 15:19
Kwachon, did you intend to say "... applying rudder ... to slow and eventually arrest the rotation. When the yaw rate has dropped or stopped, backpressure should be eased off ..."? In many types you'll be waiting a long time for anything to stop if you hold the stick on the back stop, and may well cause a rather rapid transition into something a little more aggressive in the opposite direction.
As we all know, the POH will have the optimum answer.

HFD

captainsmiffy
26th May 2009, 16:20
What is this 'picking the wing up with rudder?' Surely everyone on this forum understands that the rudder is used to prevent further yaw. Yes, its secondary effect is roll and a healthy boot of said control will raise the wing; it is not, however, your mission in life at this stage!

Furthermore, many wings with washout will stall much more inboard and you will thus have a modicum of aileron roll control. Problem is, you don't know how close to the stall that the wingtip is; using aileron will locally increase the angle of attack and you might just get bitten! 99 times out of 100 you will get away with it but on the one occasion that you don't you will be wishing that you'd listened to captainsmiffy.....