That is interesting HN39, but is it FCS elevator related?
Is the pitch variation because of the frozen trim in 'prot' and a potential for a speed change due to say pilot commanded thrust variation (basic speed stability)....with varying degrees of FCS 'AND' elevator command at times to hold alpha prot during the flight path changes either direction? I'll have to go back and find those traces for N1 and elevator and trim.
Hands off SS, I'm not sure that the FCS will ever command ANU elevator in a 'prot' situation. But I could be wrong. Range and direction of possible neutral SS FCS elevator commands in 'prot' seems to me to be the real question.
From a flight path stable entry to alpha prot with constant thrust, the elevator only goes 'AND' or neutral. Maybe the pitch/FPA variation has more to do with the trim effect during the FPA stable periods 'prot' was exited. But I may be missing something here as to the strange air mass effects.
(edit: I see Chris Scott is asking some of the same type questions.)
Last edited by OK465; 10th Nov 2013 at 15:10.
Reason: clarified AND & ANU