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Old 20th Jun 2020, 03:54
  #1232 (permalink)  
MechEngr
 
Join Date: Oct 2019
Location: USA
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Originally Posted by FlightDetent
and even with the abundance of speed and lift available exactly for that, swept the tarmac yet twice more.

Come to think of it, perhaps they tried to stay on the ground and only abandoned that plan after the third touch, lacking the deceleration (no spoilers, no brakes) and trying not to overrun.

I probably could imagine someone not lowering the gear in the heat of such moment, and then letting the fact escape alongside the landing C/L.,

The excess speed, however, most likely over the limit for any certified landing flap - i.e. either without the landing flap out or inside the red barber pole and possibly both, is still beyond understanding.
My educated guess is that they gave the stick a yank and this deflected the elevator up, immediately producing a force down. While this also produces a pitch moment and eventually causes an increase in the angle of attack of the wing, instantaneously the angle of attack of the wing won't change, so over the short interval it pushes the plane down. A similar thing happens with boats alongside docks. Using hard rudder to turn the bow away from the dock just shoves the boat into the dock.

Had they lowered the flaps a small amount to complement the elevator that would have increased the lift without a change in AoA and gotten them away from the runway to where they could fully use elevator, but it was far too short an event for the crew to work this out after they had managed to get themselves into this situation to begin with.

Anyone have access to a dynamics simulator that can confirm or deny?
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