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Old 26th Jul 2011, 08:37
  #2168 (permalink)  
RWA
 
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Sorry we seem to be disagreeing so much, Poit.

Quoting Poit:-

Would you not agree that the nose-up request was from the pilot flying (the left part is irrelevant after had correct the roll right and not necessary for the report).
You’ve flown light stuff, same as me. You’ll know that one almost never uses the stick in one dimension, ‘coordinate the controls’ is the rule. A bank usually entails a loss of lift and also produces a turn. My best guess is that, in order to get back on course and also maintain height, the pilot put on opposite bank and also used a touch of up elevator – and then levelled out. All perfectly normal. And, as I also said the PNF then read out and cancelled a couple of messages, in a pretty calm manner; if the PF was busy standing the aeroplane on its tail the PNF would surely have been saying different things (to say the least )?

(In this connection, I dislike the tendency of some (particularly that newspaper article) to suggest that the PF was ‘inexperienced.’ If you look him up, you’ll find that he had the best part of 3,000 hours in his logbook, including about 850 on the A330).

"Also, you are quite incorrect about 'next mention' of nose up inputs being 'quiet some time later'...do your research mate:"
Don’t recall saying that? I thought I wrote, ‘much later on’? The BEA’s (very thin) report times the ‘left noseup’ command at ‘2 h 10 min 05.’

The next ‘event’ the BEA describes is the ‘zoom climb.’ No mention of any noseup inputs before or during that; indeed it describes nosedown inputs. All the evidence is that the PF countered the climb and pretty well got the aeroplane back to level flight. The next event is timed as follows:-

“At 2 h 10 min 51 , the stall warning was triggered again. The thrust levers were positioned in the TO/GA detent and the PF maintained nose-up inputs.”
I make that 46 seconds between noseup inputs? Surely that’s ‘much later on’ in the context of an accident that only took about four minutes from start to finish?

May help if I explain that I tend mentally to break this (and any other) accidents down into phases. Lacking proper information form the BEA, I currently see these as follows:-

1. ‘Signoff’:- AP/ATH disconnect, pilot takes manual control, corrects an uncommanded bank, and begins flying ‘pitch and power.’

2. ‘The climb’:- No stick input either way at first. Then nosedown to arrest the steep climb.

3. ‘The stall’ – stall warning sounds, pilot applies standard ‘stall avoidance’ procedure at that time (apply TO/GA power and seek to minimise altitude loss). Stall warning stops.

(One thing that can’t be ‘fitted in’ to the various phases, in that we don’t know when it occurred, is that at some time during one of these phases, the THS wound itself up to ‘full up.’ Typically, the BEA note refers to it taking ‘about 1 minute’ but it doesn’t say which minute. I’d appreciate other people’s opinions at to when they think it happened?).

4. ‘The free-fall’ – aeroplane begins losing height at 10,000 feet per minute. I’m on record that my own view, on present evidence, is that the pilot(s) thought that the stall avoidance had worked and that they were in a dive, not a deep stall.

5. ‘The attempted recovery’ – somewhere above 10,000 feet, power was reduced (again, the BEA doesn’t say when) and the PF applies ‘pitchdown inputs.’ Angle of attack improves and the speed indications return. BUT – the stall warning sounds again…….

6. ‘The crash’ – the aeroplane belly-flops into the Atlantic.

To the best of my knowledge, that’s all we know so far. Comments, additional points, corrections, further information from anyone all welcome.

Last edited by RWA; 26th Jul 2011 at 10:10.
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