Could alpha-max vary with Nz ?
Quote from CONF_iture:
At time 1035 in the video, the Airbus test pilot clearly states :
"We're close to 15 deg AoA which is the maximum for this configuration"
Thanks for reminding me. I assumed you had a paper reference.
Interpreting GC's introductory speech, the video seems to date from mid-1989. I agree with you that, in 1988/9, the standard landing configuration was Flaps/Config FULL, even single-engined (subject to its satisfying the WAT figure for approach-climb performance). So the only issue is whether GC's figure of 15 deg was a reference to alpha-max. Taken on face value, it would appear to be so, but - as rudderrudderrat and I have previously discussed here - the AoA indicator later exceeds 15 for some time while GC is demonstrating the ability of the a/c to bank with full back-stick.
During the deceleration, alpha-floor appears on the FMA as GC points out an AoA of +14 (time 9:54), which is close to my Tech Manual figure of 14.5, and is quickly cancelled. The AoA seems to stabilise at +15 while the wings are level, but quickly increases to a peak of nearly 17 deg when the a/c is rolled to about 25 deg of left bank. This increase is quickly acknowledged by GC, who gestures (10:53) at the AoA indicator with his pointer, saying "... slightly increased angle of attack, it's gone to sixteen degrees... maintain that bank angle..." without any indication of surprise in his intonation.
So, despite having stated previously that 15 degrees AoA was the "...maximum for this configuration", he was not surprised or concerned that it exceeded that figure as soon as bank was applied. Unless we can find evidence that alpha-max is merely a target maximum for the EFCS when the stick is fully back, rather than an absolute maximum, I think we need to treat with caution the 15 deg figure of alpha-max for Config FULL.
Is it possible that the EFCS might retain a margin of a couple of degrees from alpha-max when the wings are level, in order to retain manoeuvre capability? Such a margin from alpha-max would cater for the case where the pilot needs to turn suddenly and unexpectedly after alpha-max has already been reached, in which case allowing bank with an associated increase in Nz (normal acceleration) might lead to the stall. If such a margin was employed, that might explain the apparent shortfall of AoA in the (wings-level) Habsheim case.