As a result, pilots were left wrestling with an aircraft that was repeatedly plunging itself towards the ground for no reason.
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All they had to to was disable the automatic trim. Pilots on a previous flight did that and they got to their destination safely.
Well, yes - but the problem then is a pilot training regimen that leads them to try to fix the autopilot, first - rather than teaching them to immediately switch it off and fix it later.
I have no doubt veteran US military pilots wouldn't have spent two seconds worrying about why the autopilot wasn't doing what it was supposed to.
Exactly. The other pilots figured it out. What really bothers me about that crash are the reports of 26 pitch up/down maneuvers. Ok, yeah, got it...the pilots were fighting what was probably MCAS activating due to a faulty AOA sensor. Apparently the pilots were capable of overriding or at least countering the auto-trim. So why 26, why not 27, 40, 100...whatever it took to keep the aircraft in the air. Two pilots, one stays on the stick and trims up continually if need be. Let the other pilot call the ground for help, run checklists, etc. Fly the aircraft.
I really don't understand why they gave up and let the aircraft fly into the ground. I don't care if they were getting stick-shaker, stall horns, whatever. If there's ground in front of me, I'm pulling up. If I'm going in, I'll pancake in rather than nose in. After the first few excursions I gotta believe they should have realized in spite of what the warnings were telling them they weren't actually in a stall.
The only thing I can come up with is they were maybe over-trained, or more precisely over reliant on their procedures. As I understand it, in a 737 the stall recovery / stall avoidance maneuver is to gently apply forward pressure on the control column to lower the nose, reduce angle of attack. Once that is achieved, increase thrust to recover airspeed. The faulty AOA sensor apparently caused the computer to repeatedly activate the stick shaker and maybe even the stall horn. Ok, the pilot did as he was trained, and/or MCAS did it's thing. Then the pilots tried to recover altitude, re-establish the climb or at least simply arrest the descent??? But at some point they either stair-stepped into the ground or they believed the systems telling them they were in a stall. I realize I'm biased, my personal flight experience has been in a high performance aerobatic aircraft that we fly seat of the pants. (other than approach) It is a very forgiving little beast that gives you plenty of feel for how it is flying, mushing very gently at stall. Maybe in a 737 there's no real flying by feel, by just looking out the cockpit at the horizon and saying yeah, I've got thrust, I've got airspeed, and I've got the horizon on the nose - I'm doing ok no matter what the computer is telling me...