Hi there
About the reasons why the PF initially pitched up the AC with a high thrust index: could it simply be the implementation of "manoeuvre d'urgence" in cruise phase ? (see the AF C/L "unreliable IAS / ADR check proc", the "manoeuvre d'urgence" is page 121 of
http://www.bea.aero/docspa/2009/f-cp...cp090601e1.pdf)
But this "manoeuvre d'urgence" is CLB/5°... not TOGA/16°.
Will we know the procedures that were implemeted and the way they were through the CVR ?
Is the nearly saturated THS nose up angle of 13° a consequence of the autotrim and of the (integrated/lagged) repeated nose up orders ?
situation awareness:
- 13° THS nose up angle: were the pilots informed of this ? If so, a manual trimming back to lower angles would have been their only hope then ? (related SOP ?)
- altitude/vertical speed monitoring: the 1st response to the 1st stall alarms was to pitch up/climb (manoeuvre d'urgence ?), then pitch down orders reduced the VS and stabilized the altitude around FL370 (waiting for the CPT). Latter, the CVR shows that crew was aware that the AC was closing FL100, but no early mention (in the last BEA release) of a rapid descent rate (VS).
- attitude/thrust monitoring: the pitch & thrust procedure (AP/ATHR OFF) or the "manoeuvre d'urgence" are about setting these two fundamental parameters (even on CLB/5°), and the crew tried to compensate for the roll excursions, so the crew was presumably monitoring the artificial horizon ? Though the pitch angle reached 16° at FL380, and presumably remained high on the artificial horizon (one of the reliable parameters).
- stall alarms & pitching orders: at one point (CDB was back), pitch down orders were applied with a reduced thrust, and the AoA was reducing... but it restored the validity of the airspeeds and reactivated the stall alarms: a few contributors suggested that this might have been a highly misleading factor (among many others !) urging the crew to abord these nose down orders. But nothing is said by the BEA about the following pitching orders. The BEA does not yet tell whether the word "décrochage" (stall) was heard in the cockpit (CVR).