Originally Posted by
ATC Watcher
There you might have a chance to make a 180 if the end is blocked, If you stay in the middle or on the others side , your turn will be far wider and part of it will be inside the downdraft.
Honestly I don't think they ever planned executing a 180 inside the canyon. even if flying close to one ridge it would be really unlikely you could do that with an airliner in a halfmile wide canyon.
And that is what puzzles me.
Let's have a look at the options:
1) Turning too early
Maybe they wanted to fly along the outside of the mountain and turned too early as per mcgyver81's theory (which really has some merit to it).
=> That would require that they couldn't see the left ridge of the canyon. That was the aspect I was referring too with my rough calculation of the turn radius. Conclusion: a normal turn would have brought them as close as a quarter mile to the left canyon wall.
They apparently flew FL2000 which is 1800m (impact at ~1850m) and thus ~200m below long parts of the left ridge which itself is slightly higher than the right ridge. So they would have to be able to see the right ridge to skim along but not the higher and probably closer left ridge. Still absolutely possible depending on local weather phenomena.
1a) Turning too early without continuous sight of the mountains
They just saw the right 'entry corner' of the canyon briefly, took it as a reference point and started turning into a direction which would lead them alongside the mountain range without seeing the right ridge after that or seeing it only intermittedly.
2) Deliberate 'canyoning'.
Requires less technical violation of Occam's razor (see explanation above) but seems so much more irresponsible to do that in an airliner in a mountaineous area with which you are not familliar that it might be less probable than the first option despite requiring less assumptions.
3) completely blind and unaware turning into the canyon thinking they are clear of the mountains.
=> Quite improbable, as that would be a hell of a coincidence not hitting any ridge prior to impact.
Did I overlook any other option?