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Old 28th Jun 2010, 19:54
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Lonewolf_50
 
Join Date: Aug 2009
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Investigators have concluded that, during the take-off roll, the slats retracted - as designed - in response to signals indicating deployment of thrust reversers on the two inboard Rolls-Royce RB211 engines. The right-hand reverser signal was triggered at 125kt and the left-hand at 160kt.
But neither reverser had been activated, and British Airways engineers examined the aircraft (G-BYGA) to trace the source of the false signals. The inquiry concluded that, although the reversers were stowed, their translating cowls were nevertheless seated relatively far rearwards.
As the 747's engines wound up to high power, and the aircraft accelerated, sensors monitoring the cowl positions transmitted incorrect 'reverser' signals. The slats retracted because of a logic process designed to prevent them being struck by efflux air from activated reversers.
At risk of sounding vastly ignorant, might a design strategy for such a capability, thrust reversers, tie in to a weight-on-wheels switch?

I guess the risk there is the circuit goes bad, and you don't get them when you need them. One could design the circuit so that unless powered, it can't turn thrust reverser function off ... where are the holes in this idea?

For one, which wheel?

Am I right in guessing that an auto-thrust reverse function is very handy in some tight landing situations?
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