RegDep/FE Hoppy
Very grateful re: your link to the NTSB report on NW6231. That's the flight I have always thought of when you mix pitot tube icing and aerodynanic stall. Probably a generational thing. Showing my vintage.
But for the BEA, and from the stance of investigating the loss of AF447, I still think TE901 and have done since my very first skim of their 27 May report. Why would pilots continue to pitch-up the nose on a stalled aircraft from 38,000ft all the way down? It's been done all the way down before, see above, but other factors will surely come into play in the full CVR and FDR (with details of the aircraft and its systems responses).
As initially inexplicable as flying a perfectly good aircraft into a 12,500ft volcano at 1500ft feet? Eventually, you get to the truth - ANZ flight crews unaware of the MSA or else ignoring them on "sightseeing" flights, McMurdo ATC giving permission to descend well below any ANZ SOP MSA (the radar not picking-up the plane/interrupted HF communications as clues to an intervening land mass?), no Antarctica "whiteout" training for the flight crews, and then the plane being programmed the night before to fly towards Mt Erebus rather than down McMurdo Sound (as per the earlier flight crew briefing) and without the flight crew even being notified.
The flight crew doing something which appears inexplicable at first sight, training and operating issues coming out "in the wash" (haven't Airbus already changed their recommended high altitude stall procedures, focussing less on power application and more on a willingness to sacrifice height and get air flowing over the wings again, in the intervening period between crash and CVR/FDR recovery?) - sound familiar to AF447? Intense media activity (albeit nothing as compared to the pressure that McDonnell Douglas were under in November 1979 in relation to their DC-10s, post-Paris and Chicago crashes - I bet the engineer who downloaded all the INS data from the wreckage to prove a controlled flight into terrain got one hell of an Xmas bonus that year!). BEA may additionally have aircraft issues to add to the mix with AF447 (there are a number of troubling issues, particularly in the short time between A/P cut-out and the stall beginning at FLT380).
Alot of speculation in the meantime, on still limited known facts from the CVR/FDR, but some excellent technical input from this website. Just don't get overly fixated with that last sad few minutes (I know it goes against the grain for us aviators), because most of the chain was completed and in place before the A/P computed "do not compute" and handed the plane over to the flight crew. Think how small a trigger, the ice-defective FOHE grill on the Trent 800 engines, was to bring down a B777 on final approach to LHR. The margins are tiny.
And a salutary reminder to today's aviators, airlines and manufacturers of what the great Captain D P Davies wrote (well, more or less) over 4 decades ago - if you are left with a choice of causing an aerodynamic stall or causing anything else, probably best to go with the latter...........
That's all gentlemen (and probably a few ladies), from me, until after the next BEA report. Keep up the good work/keep the posts coming.
We have travelled less since December 1974 than everyone had hoped (the Colgan Air propliner, not just AF447, and even with the Aeroperu and Birgenair "wake up" calls in the 1990s).