Originally Posted by
GlueBall
Liftoff was at 5:38;00, 5:40:42 passing 305 kts, 5:41:20 Clacker (VMO 340), 5:42:10 still found time to talk to ATC and change heading bug, ...that's 1:33 before impact, while nobody thought about MANUALLY pulling back the thrust levers. ...Helloooo.
They were trying to climb, and they had the stick shaker active. Reducing thrust when you try to climb can be a bit counterintuitive, wouldn't you say? Also, reducing thrust when you have the stick shaker active is usually not the best idea. Especially close to the ground. Also the speed, as measured on the left side, stayed at about 340 knots for about 3 minutes. It seems the pilot flying was controlling the speed using the elevator, pulling harder when it was going over 340. They only went significantly over 340 during the final dive.
So I doubt they were unware of their speed and the clacker. They probably wanted the speed, probably hoping it will allow them to climb faster and it might also make the stick shaker go away. It's like a terrain avoidance maneuver where you pitch up until the stick shaker activates. You actually want the stick shaker to activate, it tells you are doing your best to climb. And you keep it around that point, close to a stall, with the shaker intermittently activating, until you clear the terrain. Something similar may have been going on here, they may have wanted to keep the speed close to VMO.
Of course, you can then question why the pilots didn't pull even harder to climb faster, instead of allowing the speed to reach 340. The column displacement is never more than about 66% nose up in that 3 minute interval they kept the speed at VMO. But then you have to remember the stick shaker. They may have been afraid to pull harder because of the stick shaker. That may also explain why they didn't fully revert the nose down trim from MCAS when they had electric trim available. They may have been reluctant to trim and pull nose up believing they could be near a stall.
They made mistakes that are hard to explain, like attempting to enable the left side auto-pilot, and not realizing the instruments on the right side were the ones working properly. But I don't think allowing the aircraft to reach VMO is one of those mistakes.