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Old 12th Jun 2011, 17:44
  #1849 (permalink)  
A33Zab
 
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Why AOA is disabled <60 kts?

@MB.

A33Zab
Quote:
Maybe, not sure! this lower CAS speed limit is introduced for maintenance.
That would be an unfortunate tail wagging the dog approach to a minor engineering problem.

With a computerized aircraft you no doubt have maintenance modes you can enter (that are locked out during flight operations). Besides, how do you test the stall warning system on the ground then?

The 60 knot limit below which AOA is disabled more than likely results from another corner of the envelope. Something such as flow impingement from thrust reversers at low speed (on the ground of course).
Valid and logic too.

MCDU System Tests mode option is disabled after you entered your flightnumber. But hey.....because its a computerized aircraft it can be fooled even in flight! Just have to know how to set the proper bit.

Depends on the type of test: Stall Warning system is tested through MCDU, drives AOA to predetermined test angle by means of the -dual purpose -dampingmotor and set a false speedsignal.
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