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Old 27th Jul 2008, 03:12
  #1555 (permalink)  
CONF iture
 
Join Date: Jan 2005
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330 versus 777

I do think a 330 would have done very well with hopefully no casualty as well.
But my view is slightly different from Chris Scott view

By manually fire walling the thrust levers, Go Around Auto Flight logic is triggered.
FD bars command SRS (Speed Reference System) in this case probably VAPP (VLS + 5kt)
As speed was already around VLS or even below and as bizarre we might think FD will command aircraft to pitch down (waiting for thrust increase …)
Note: AP is still ON unless manually disconnected or sidestick manipulated.
Now aircraft is below G/S but still at VAPP.
Houses are getting closer … time to refuse ground contact by pulling the sidestick (AP now disconnects)
Speed is bleeding AOA increasing to AlphaPROT … (maybe AlphaMAX but I don’t think AlphaMAX is achievable below 100 feet …) STALL protection remains active.
Less drag in the early portion and better ground effect, aircraft touches down somewhere in the grass in a nose high attitude.
V/S at touchdown depends on pilot fortune in the overall process.

Would be nice to validate (or not) this scenario on a 330 sim if ever able to simulate the thrust deficit with THR LVR in TOGA gate.



BA038 touched down in a very flat attitude witch means it had stalled already.
Combination of soft terrain + landing gear impact absorption made things very comfortable for passengers at least.

Too bad AAIB still keeps very secretive on aircraft performances as well as on front crew actions …

Last edited by CONF iture; 27th Jul 2008 at 12:19.
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