Originally Posted by
Ian W
How about the NNCs in all 737s for Runaway Trim? oh of course it is not 'runaway' as it is only repeated (reads from dictionary) nose down trim, so I will let the Stab Trim fly me into the ground rather than switch it off.
Would you really let trim carry on monotonically trim down 2.5 units every 5secs and not switch it off? l can only assume that you would. It is really immaterial why the trim was operating it could be a now dead rodent chewing through an electric cable, you just want the trim to stop and two switches that have been there forever allow you to do that. I am sure that Boeing is aghast that their NNCs for trim runaway were being read in such a contracts lawyer fashion. Perhaps they should review the semantics of all memory items and NNCs/checklists and any training that reinforces those limiting semantics.
Yes recognizing the trim issue is the heart of the matter. That was exactly my point. You cannot make this into "switch off the AP and fly the plane"-scenario. A pilot with poor manual flying skills but being able to identify the issue does much better than a skilled flier who isn't able to identify the issue.
It doesn't help you to switch off AP and AT and stabilize things by flying "power and pitch". You can't because you don't achieve a stable pitch.
So hence my real point, the challenge: Show me that up until six months ago anyone suggested making "stab trim cutout" part of a "disengage auto and fly the plane" if you don't have a clue what the issue is.
The "should they have been able to catch on to the trim issue?" discussion has been done ad nauseam. In my personal opinion the only way to hypothetically get the truth there would be if you could find 20 average pilots who had been in coma for the last six months and put them through a surprise sim scenario replicating an actual MCAS-misfire.
Then we would know how the average pilot would have done.What people with all the facts are now convinced they would have done is not relevant evidence to me.
I bet that if you asked the average px if they were confident that they'd get a life jacket on in case of a water landing landing the vast majority would say yes. They've seen the briefing a gazzillion times. How hard can it be?
Yet we know how many out of a 150 px in the "Sully flight" actually managed to put on a life jacket properly waist strap and all. Was it a three digit number? Was it a two digit number?