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Old 2nd September 2001 | 02:39
  #62 (permalink)  
cosmo kramer
 
Joined: Jul 2001
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Covenant

Check this link for information about Low Aspect Ratio Wings at High Angles of Attack

There are some graphs that quite clearly explains what happens to delta wings at high AOA.

At high angles of attack, several phenomena usually distinct from the cruise flow appear. Usually part of the wing begins to stall (separation occurs and the lift over that section is reduced).

but,

When the sweep is very large, or aspect ratio low, this approach does not work. Separation tends to occur near the leading edge of the wing, but unlike in the low sweep situation, the separated region is not large and does not reduce the lift.

--

When the vortex burst occurs on the wing (as opposed to downstream of the wing) the lift drops substantially.

but,

For many SST designs, however, the maximum CL may be predicted by assuming that the vortex does not burst at the maximum permissible angle of attack.
All of the above is backed up by a lot of formulas that doesn't make sense, though, to "normal" human beings

you wrote:
Without a whole load of power at your disposal, increasing angle of attack is an inefficient trade-off to gain a little short-term lift for a lot of airspeed - much more so than with a conventional wing. Sooner or later gravity will inexorably take over and the aircraft will spin out of the sky.

If that's not stalling, then I don't know what is!!
I think most here would define stall as the state of flight where the critical angle of attack has been exceeded (i.e. the wing stops producing lift). Drag is another matter and an excess of drag is not the same as a stall, although the consequences may be the same eventually.

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But is any of this, or how the Captain flew the aircraft relevant? Isn't it more relevant why they ended up in the messy situation that they did?

[ 01 September 2001: Message edited by: cosmo kramer ]
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