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Old 27th February 2009 | 19:50
  #673 (permalink)  
HarryMann
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Joined: Jan 2008
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From: Herts, UK
Originally Posted by Atreyu
Besides no-one can be sure of what the crews actions were before impact, the only clues we have are the physical evidence of the wreckage, which do suggest a Staines-esque IMPACT, note the word impact people, I'm not suggesting the same causes at force here, but the tail seperating from the main wreckage and lack of fire along with a relatively small debris field SUGGEST a stalled condition on impact, as in the Staines disaster.
I'd say that a stretch far too far, for you and so many to keep using the tail-separation as some sort of evidence of a fully stalled condition with commensurate rates of descent ... two of us (at least) here keep saying... this aircraft did not have a particularly high rate of descent at impact - everyone would be dead!

Originally Posted by deSitter
At the right speed and attack angle a partial stall can occur, without buffeting, where the flow is still more or less laminar but there is a great reduction of lift - a sort of "flying squirrel" regime of flight which is really more like an air-cushioned fall.
Laminar flow is a misuse of the term, it is a boundary layer condition (laminar/turbulent) and so often confused with separation and stalling it drives aerodynamicists nuts!
Leaving that out, I agree, but a few pages back called it 'waffling along' I believe in a partially stalled high drag regime. Which points us back to Atreyu's post above... gross lifting ability is NOT lost, but forward speed is steadily if not rapidly decaying unless sufficient thrust is available, taking us into the serious lift-loss regime.
These are 1g, unaccelerated stalls, and few wings today exhibit what so many seem to think they see when looking at traditional 2D Cl~Alpha curve. For one, the sweep and AR ameliorates the (classic sharp stall) condition, let alone the profile with flaps and slats too...
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