737NG stall warning
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737NG stall warning
Will you get a stall warning (shaker) by a false low airspeed indication (on one or two PFDs) on the NG if the alpha vane senses no stall? I am aware that you can get stick shaker at any airspeed if the alpha vane senses a stall ( such as in a secondary stall) but will but will you also get a stall warning in the above situation?
Last edited by president; 2nd Dec 2012 at 23:05.
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737NG stall warning
Maybe I can simplify my question. In cruise your airspeed on one side suddenly drops to 100 knots indicated. Does the stick shaker kick in if the alpha vane is not sensing a stall?
From practical experience I know that when the Captains pitot static system is playing up and the airspeed show very low numbers on the left side, but the first officers side is showing normal speeds, you will get the stick shaker.
I'm not sure if that helps with the AOA question though.
I'm not sure if that helps with the AOA question though.
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Maybe I can simplify my question. In cruise your airspeed on one side suddenly drops to 100 knots indicated. Does the stick shaker kick in if the alpha vane is not sensing a stall?
The stick shaker will activate as the speed displayed is the speed used by the SMYD and it is the SMYD that sends the stall warning to the control column.
The AOA is NOT used for the such speed floor stall warning.(low speed).
If the AOA reaches its critical point,the SMYD will send the same signal(stick shaker) AND the EFSM will increase eletor down force with an increase in hydr A pressure.
Last edited by de facto; 4th Dec 2012 at 02:03.
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Yes you can get false stall warning. Not just stall warning.
EGPWS(except for modes 5-6), overspeed warning, Mach trim fail, speed trim fail - all are liable to false indications with an unreliable airspeed.
Flap load limiter may even prevent flap extension beyond 30. Although you can use alternate flaps to bypass the load limiter.
EGPWS(except for modes 5-6), overspeed warning, Mach trim fail, speed trim fail - all are liable to false indications with an unreliable airspeed.
Flap load limiter may even prevent flap extension beyond 30. Although you can use alternate flaps to bypass the load limiter.
