^Scary. The plane doing the opposite of what is required and in a way that leaves the plane to nose dive, plus this happens for a control that is mostly used when landing!!! There were quite a lot of fatal accidents and close calls attributed to that. I guess the timing of these MAX accidents and the perceived 'shadiness' is what makes it such a bigger deal?
The Seattle Times found that the left switch on the 737 NG model is capable of deactivating the buttons on the yoke that pilots regularly press with their thumb to control the horizontal stabilizer. The right switch on the 737 NG was labeled “AUTO PILOT” and is capable of deactivating just the automated controls of the stabilizer.
Yep. I wonder if they got this right. I think the "master" (left) switch should probably kill the motor, completely. But I suppose it might just disconnect the pilots' controls, in case of a button/switch fault, so that the autopilot can still be used? And the other switch USED to enable/disable just the FCC/autopilot control over the motor. If I understand the article, correctly, both switches now cut all motorized trim movement. 00, 01, 10 all mean the motor is disabled. 11 = motors enabled and accessible to pilot manual trim button, autopilot, and MCAS. It's funny that they can't remove a switch due to red tape, but they can apparently rename it?
In any emergency, it seems you never do anything but cut both switches, so it shouldn't have any immediate effect on an emergency. But it means that after stabilization, a fault of any of these 3 controls means you can't re-enable any of the others after, say, further troubleshooting and/or call with maintenance crew. But I agree with the Times that if the pilots had the ability to flip off just MCAS/autopilot control and leave the manual trim buttons intact, and they knew this was available, that ET302 esp might have been ok. I think I posted something to that effect a week ago. These pilots apparently knew what they were doing when flipping stab trim back on, but maybe weren't prepared for the immediacy/scale of the MCAS response or the enormity of how much manual trim they really needed to apply, in addition to allowing the plane get too fast for the condition and not knowing or anticipating the effect that had on trim and elevator control of the plane. It sure seems like they were trying to fix the trim with the wheel and would surely have enabled only the manual trim control buttons if they had and were aware of that option. They had at that point realized there was a left alpha vane malfunction.
One thing that seems obvious in hindsight is some sort of notification when MCAS is activated. It might have just gotten lost in the other noise, stick shakers, clacker alerts, ground proximity warnings. But it is evident that when a plane is crashing, pilots don't necessarily look straight down between the seats. I imagine if they even heard/noticed the trim moving, they both thought the other pilot was trimming UP. If they had been aware, I bet even GoJ's "Playstation pilot" takes some corrective action, hopefully in time.
"uncommanded movement of the {737} aircraft's rudder". It was the same actuator valve as the elevator... so much for hydraulics being reliable.
Wonder if the extreme control surface forces/pressures in these accidents might be revealing some new, still unknown fault in the hydraulics?
Totally unrelated one of the strangest accidents I have come across. The ghost flight.
5 seconds too late, maintenance guy, "oh, yeah. Hey, can you check that switch I might have forgotten to flip back?"
Everyone in the plane puts on an oxygen mask except the pilots?
Autopilot continues doing its thing, ascending to 40,000 feet, even when the cabin has no pressure?
Flight attendant wakes up and is actually a pilot. But the fuel runs out 10 seconds, later?