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Old 11th Dec 2013, 23:41
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DozyWannabe
 
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Originally Posted by CONF iture
full back stick and alpha max is commanded and maintained.
No. Read the extracts again. "Alpha Max may be reached" - not "will be reached" or "will be commanded and held", but "may be reached". The second document refers to commanding "a maximum AoA (approximately corresponding to CL Max)" - it doesn't refer to "Alpha Max" (as in the vertical line on the graph) at all. This is because the calculated AoA to provide optimum lift performance will vary depending on the conditions.

Hopefully you will come up with valuable argumentation to justify that the airplane had no intention to deliver anything closer than 2.5 degrees of alpha max ... ?
I still don't know where you're getting this 2.5deg figure from - a reference would be handy.

(Though if Alpha Prot is 2.5 degrees less than theoretical Alpha Max, then that's consistent with the FCTMs - but ordinarily I'd expect the optimum AoA to be closer to Max than Prot)

Regardless, if the aircraft behaves as the FCTM describes, then the calculated "optimum lift" AoA will always be somewhere between Alpha Prot and Alpha Max (up to Alpha Max itself). The FCTMs explicitly use terms such as "may be reached" and "approximately", which clearly indicate that achieving Alpha Max is not guaranteed if the conditions aren't right.

Is it again disinformation or just ignorance on the report ?
I don't have a translation of the full report, just extracts. I'm working on the assumption that significant back-stick would be required during the flypast to maintain altitude, as releasing the stick commands a return to Alpha Prot (and a shallow descent).

Last edited by DozyWannabe; 12th Dec 2013 at 00:05.
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