Old 28th Jul 2010, 23:12
  #94 (permalink)  
john_tullamarine
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Join Date: Apr 2001
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In the case of the 737-300 ..

With the caveat that the OEM's advice for a particular aircraft is likely to be based on sensible FT work and, therefore, one should observe it .. there are a couple of considerations with engines sticking out in the front like most of today's twins -

(a) if the engine is underslung (as nearly all are) the low thrust couple doesn't help

(b) if the upset has been allowed to progress to a high alpha, there is a problem observed once power is applied. As power comes up, with the change in flow around the front of the nacelle (and through the prop disc for turboprops) there arises a significant up-force at the nacelle lip (or prop disc).

Both of these are destabilising and reduce the longitudinal static stability. The end result is that the pilot finds him/herself in hot water.

The main emphasis for any recovery should be skewed toward reducing alpha and then, at an appropriate time for the Type, increase power.

you always STOP trimming at xkts above the stall speed

and the certification stall data (and the AFM techniques) are based on a similar approach to the matter ie, if the trim has run too far nose up then the pilot's existing problem are complicated further.

Gosh, what an absolute surprise

.. well, after all, it IS a Lockheed product .. not like those other agricultural animals.
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