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Old 6th Apr 2016, 07:35
  #69 (permalink)  
FullWings
 
Join Date: Dec 2003
Location: Tring, UK
Posts: 1,845
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I think the previous paragraph needs a mention as well:

"In this situation the pilot should trade altitude for airspeed, and maneuver the airplane's flight path back toward the horizon. This is accomplished by the input of up to full nose-down elevator and the use of some nose-down stabilizer trim. These actions should provide sufficient elevator control power to produce a nose-down pitch rate. It may be difficult to know how much stabilizer trim to use, and care must be taken to avoid using too much trim. Pilots should not fly the airplane using stabilizer trim, and should stop trimming nose down when they feel the g force on the airplane lessen or the required elevator force lessen. This use of stabilizer trim may correct an out-of-trim airplane and solve a less-critical problem before the pilot must apply further recovery measures. Because a large nose-down pitch rate results in a condition of less than 1 g, at this point the pitch rate should be controlled by modifying control inputs to maintain between 0 g and 1 g. If altitude permits, flight tests have determined that an effective way to achieve a nose-down pitch rate is to reduce some thrust.”

Also, whacking on loads of bank near the ground I would regard as the ultimate, last-ditch, do-or-die manoeuvre, probably initiated because of a fault with the flying controls or some issue with the CofG.

If you are way out of trim on the stabiliser, at some point you’re going to have to trim it otherwise you’re going to spend the rest of the flight going around in small circles until the fuel runs out.

I think I stand by my statement. You need to regain elevator authority and as soon as you have it, i.e. you get the ability to reduce pitch back, you can stop trimming. At the point you realise that you can’t get the nose down are you in an upset or quickly approaching one? I would have said the latter, so decisive corrective action will get the attitude under control and thus the flightpath before any more extreme measures are necessary.

Last edited by FullWings; 6th Apr 2016 at 08:57. Reason: Early morning confusion...
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