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Old 11th Nov 2018, 20:03
  #1009 (permalink)  
Join Date: Nov 2016
Location: Lakeside
Posts: 428
Originally Posted by hec7or View Post
Pilots are encouraged to disconnect the automatics and fly manually if the system is doing something unfamiliar, in this case, by disconnecting the automatics, the MCAS is active.

So, in the event of an AoA sensor failure a "system" induced stab trim runaway occurs...which admittedly does have memory items.

When they design these safety enhancements, why don't they tell us?

The inhibited "stall" aural warning at high AoA during high AoA on AF447 is another example of design engineers assuming pilots will behave like monkeys, where the warning was inhibited at high AoA and activated when the crew reduced the AoA. Also the Colgan Air flight 3407 Dash-8 Q400 at Buffalo would in it's final stages have generated GPWS aural alerts concerning the glideslope deviation together with stall/low airspeed warnings, one warning requiring a pitch up and the other requiring a pitch down, which could overload a tired flightcrew.

Clearly the safety systems require a rethink
On Colgan, the bugs were set high, the Stall Warn activated with twenty knots left of room. Pilot pulled, eventually wrestling with the pusher all the way down. GPWS? He was pulling with all his might as it was. Did he pull harder with GPWS command? Dunno.
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