AF 447 Thread No. 9

[Turbine D]

Hi PJ2,

Relative to the QRH drill, I have some questions. As in the case of AF447, you are cruising at 350, M .82, 2.5º pitch and an N1 setting of 95% (as referenced on page 183 BEA's final report for level flight). Due to expected turbulence, a reduction in M is dialed in to .80 resulting in a reduction of N1 to 84% by AT. Suddenly the AP disengages, the AT disengages and AT lock occurs. At this point, according to the QRH drill, the pitch should be set at 5º and the thrust levers must be moved to climb detent at which point one needs to know from the tables to reset pitch and power based on the aircraft wight and altitude. My first questions would be aren't the thrust levers already in the climb detent? Does the thrust lock latch a 84% N1? if so, does this give much time to figure the right pitch and power setting before a real stall warning occurs?

But when I see the tables, the reset for pitch is 3.5º and 90% N1 for a M of .82 based on altitude and weight. This seems a little low on N1% with a 3.5º pitch setting based on what is referenced in the BEA report for level flight at the altitude being experienced. I recognize at the upper end of the power settings at 350 there isn't much power left to be had, but the differences seem confusing to me more than anything, perhaps I am missing some finer points. Any thoughts? Is my logic off?

P.S. The source of pitch and power table I used came from the BEA final report, Page 104. Additionally, the BEA Interim Report #3 gave the following N1% power settings from each engine as follows:
At M .82 - True N1% 100.4/99.8
At M .80 - True N1% 98/98