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Old 23rd Mar 2016, 15:23
  #540 (permalink)  
ManaAdaSystem
 
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You have a major flaw in your notes, de facto.
You are not required to press TOGA to get into WS mode. Only if you are on an ILS. This is from the FCOM. In reality it matters very little as we press TOGA as part of the manouver.
And your notes does not say a thing about altitude capture being inhibited during WS. In my experience, it is not. Nowhere is that stated in the FCOM.

B737SFPs quote from the Boeing article is very close to what I believe happened here. Read it and weep.

From the 737 NG FCOM:

Takeoff or Go–Around
If windshear is encountered during F/D takeoff or go–around, the F/D pitch command bar provides commands to maintain the target speed until vertical speed decreases to approximately +600 fpm. At this point, the F/D pitch bar commands a 15 degree nose–up pitch attitude. If vertical speed continues to decrease, the F/D continues to command a 15 degree pitch attitude until a speed of approximately stick shaker is reached. It then commands pitch attitudes which result in intermittent activation of the stick shaker. As the airplane transits the windshear condition, the F/D programming reverses. As climb rate increases above approximately +600 fpm, the F/D commands pitch attitudes which result in acceleration back to the target speed. The A/P and F/D both operate in a similar manner during A/P or F/D go–around.

Approach and Landing
If windshear is encountered during an ILS approach, both the F/D and A/P attempt to hold the airplane on altitude, or on glideslope after glideslope capture, without regard to angle of attack or stick shaker limitations. Airspeed could decrease below stick shaker and into a stall if the pilot does not intervene by pushing the TO/GA switch or disconnecting the A/P and flying manually.

Last edited by ManaAdaSystem; 23rd Mar 2016 at 15:54.
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