PPRuNe Forums - View Single Post - AF 447 Thread No. 9
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Old 8th Jul 2012, 15:13
  #163 (permalink)  
OK465
 
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...but for by far the longest time the aircraft was assumed to be held at constant pitch attitude
OG:

This is somewhat of a conundrum in the sense that when you reach -10 degrees, as you say a long time before actual recovery, to hold that pitch attitude do you...

1. release the SS, i.e. FCS positions the elevator to hold what?

Still stalled, It's likely the elevator would go right back to full ANU to hold ~1G and the existing flight path which is quite a bit steeper downhill than 10 degrees at this point. Rule out SS release?

2. or is the SS manipulated, i.e. what is necessary, considering FCS elevator response, to hold a constant pitch attitude while stalled? If not continuing full forward, how do you do this? Some occasional aft SS necessary? (rhetorical )

The FCS has a pretty big say in what you actually get here in practicality, although the theoretical side is certainly sound and I understand that's as far as you intended to take it or that anyone could take it.

In practicality, I wouldn't come off the forward SS stop (with whatever extended nose down pitch rate was actually available) until I knew that I was 'flying' again. This approach, of course, may change some of the values.

Last edited by OK465; 8th Jul 2012 at 15:15. Reason: I see your edit now
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