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Old 8th Dec 2011, 16:29
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JW411
 
Join Date: Oct 2001
Location: UK
Age: 83
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Now then chaps; I have been watching this disertation for a few days and I sadly feel that I need to correct some misunderstandings about stall recovery in transport aircraft.

For those of you out there who don't know me, I was still instructing and examining on 4 engined jet aircraft until two years ago.

There seems to be a growing argument that the technique of "powering out of a stall" in such aircraft is a crap idea and that the only answer is to stuff the nose down like you were taught in a Cessna 150.

I am extremely familiar with teaching and examining the license requirements and for obtaining a type rating on such aircraft.

Recovery from an approaching stall with either a clean wing or a wing with minimum flap was taught as "relax the back pressure on the control column and apply full power". If conducted properly, the loss of height was in the order of 200 ft.

If you stuffed the control column forward and carried out a Cessna 150 recovery, the loss of height would be about 1,000 ft.

Why?

Well, it is very simple. The parameters required by JARs etc were that the exercise began with the onset of the stickshaker. Now every MS Pilot who has decided to infect our website will be able to tell you that the stick shaker will activate at approximately 11 knots or so above the actual stall.

Therefore, the recovery from stick shake by applying full power and easing forward on the control column is perfectly valid for the aircraft has not actually got anywhere near stalling.

In other words, the aircraft was never stalled in the first place.

So when did the candidate actually have to deal with a proper stall?

The final stall on the type rating test consisted of turning on to base leg (for example) with 30 degrees of bank, the gear and land flap down and with the power set at approach setting but at the same time maintaining height (intead of descending) right through the stick shaker, to pulling and pulling and pulling until the stick push activated. The average height loss through this manoeuvre was 700 - 900 feet.
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