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Old 10th Mar 2020, 05:53
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Tobin
 
Join Date: Apr 2019
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Originally Posted by yanrair
Thats it in a nutshell. That’s what you do
I remember reading the threads from before ET302, when JT610 was still the main topic and MCAS was just becoming known.

The advice given then was: "You see the trim is running away. All you do is flip the cutout switches. Then get back in trim using the wheel. Why didn't they just do that?"

But then ET302 happened, and people stated questioning whether the trim wheel could be turned at 300+ knots and 2.5 units out-of-trim.

The advice given then was: "You see the trim is running away. You get back in trim with the pickle switches, obviously. Then you flip the cutout switches. Then control the trim using the wheel. Why didn't they just do that?"

Notice the subtle change there? That's what one might call moving the goalposts.

The fact is, the "obvious" solution given by the blame-the-pilots crowd changed, and no one has acknowledged that. The fact is, the classic advice for trim runaway is to hit the cutouts as soon as possible, not futz around with the pickle switches first. If the runaway is not caused by MCAS but by some electrical fault, pilots may be wasting precious time, trim, and controllability trying to troubleshoot the switches. The "get back in trim using the electrics first, duh" advice only works if you see that the runaway is effected by MCAS. You know, by seeing the helpful little "MCAS active" light Boeing installed in all the 737 MAXes.

Oh, wait.
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