AF 447 Thread no. 4

[HarryMann]

With much discussion - some verging on serious disagreement though perhaps that is mainly in emphasis and tone rather than on facts - the following points seem to be featuring strongly where tentative agreement exists:-

1) A stall warning system that has (more than) raised eyebrows before, could be at the centre of cockpit crew confusion once the event had 'matured'
2) A THS trim system, has possibly (or effectively) 'run away' to an extreme setting, that would not be expected at high Mach and cruise Altitude. Said THS system's manual trim wheels do not light up, flash, shout or scream, nor display messages on PFD when at such an extreme setting, even when at that Mach, Alt and Config which surely must be considered a bizarre combination - so why not?
3) An AoA sensor, that whilst likely more immune from debris and/or environmental contaminants than pitot-static AS sensors, and an essential last-ditch safety device (feeding SW system), as well as providing a valuable singular (& independent) item of air data in its own right:
a) did not have its own dedicated display (matching its singular discrete origin and across-the board usefulness)
b) had its feed into the SW system inhibited/constrained in a fairly predicably dangerous fashion (that is creating a fait a complit, should a full (deep sic) stall actually occur)

It appears from reading all the above posts, that their only chance was the Captain, who fought back to the cockpit upon call ASAP, like as not assessed the situation correctly despite not having even half the history & information at his fingertips, and had begun to take pro-active steps along the right lines when old father TIME just ran out for him - I cannot help but feel fustrated even now that we have learnt so much over the last 100 years, and forgotten half of it..

That half is...

We are in WING-BORNE FLIGHT through a fairly decent & consistent layer of air and very few things matter most of the time:
other than AoA and a modicum of speed and thrust, even the latter can be dispensed with for quite a long time in most aircraft, subject to some altitude.

But AoA, not even pitch, is everything with wings and air. Both the THS system and Incidence vanes are major player in AoA matters.

Goodness - even a bit of string (albeit kevlar with a luminescent tracer in it) alongside each side-screen could have jerked someone back into the real world in this instance, no?

Ok, hand-up to hindsight... but having flown sailplanes & hang-gliders, still find it strange that the basic origins and roots of flight are ignored... even the Space Shuttle is an AoA device when back in the atmosphere, indeed, most crucially when re-entering at the very outer limits!