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I know this. I also know that there were 3 MCAS incidents. On the first one, the crew restored normal trim with the thumb switches, then turned off the stab tri

I know this. I also know that there were 3 MCAS incidents. On the first one, the crew restored normal trim with the thumb switches, then turned off the stab trim system. They had no idea that MCAS existed, they simply followed standard procedure for runaway trim. After the first crash, Boeing sent around an Emergency Airworthiness Directive to all MAX pilots with the two steps I showed. There's no excuse for MAX pilots not reading, understanding, and remembering Emergency Airworthiness Directives. It's not just me. I've talked to two 737 pilots who said the same thing.

throwaway5752 1y ago
I see in a sibling comment that you do not think the MCAS system on the MAX was well designed, and the reliance on a single AoA sensor was not a good decision. I agree. The aircraft should have never been declared airworthy. There should have been no need for an EAD in the first place. There is no excuse for putting a control system that flies the craft into the ground when there is a failure in a nonredundant sensor on a commercial aircraft. The high standards required for pilots, like Amelia Earhart, do not obviate the even higher standards for quality and safety from manufacturers.
- WalterBright 1y ago
  I suspect that Boeing didn't think it would be a problem because the runaway stab trim procedure is enough to stop it and recover. Who would have thought that trained pilots would not remember this procedure? It's supposed to be a "memory item", meaning consulting the checklist was not required. The stab trim cutoff switch is in a prominent position on the central console (not overhead or behind the crew). In the first Lion Air crash, the airplane dipped and recovered (via the thumb switches) 25 times over a period of 11 minutes. They never thought to turn off the stab trim system. It boggles the mind. Would you want to fly with a crew that didn't know what the switches on the console were for? Not me. Both Boeing and the crew are at fault. Some percentage also for whoever made the faulty sensor and the failure to see that it worked correctly after it was installed.
  - genewitch 1y ago
    Do we also blame the drivers of the Toyotas that got stuck accelerators, because any driver should know to take the car out of gear or turn the key to the off position. Right? While the car is accelerating at or near WOT? I've been in a car when the throttle got stuck open, we crashed, I hit the windshield. It happened in about 5 seconds, and the driver spent most of those giving steering inputs to avoid hitting people and furiously working the break and kicking the gas pedal. It happened because enough engine mounts were broken or broke because of a hard throttle push. Also my dad died in a single seat plane crash because the engine died several times in flight, according to a witness interviewed by a local paper; there was no investigation at all so I'll never know what really happened. At least the company that made the plane changed their name!
    - WalterBright 1y ago
      I had the throttle stick on my car once. I immediately turned the ignition off. I was a teenager at the time (and my car was a POS). The brakes are much stronger than the engine (proof: you can brake in a much shorter distance than you can accelerate). On my current car, I have inadvertently hit the edge of the gas pedal while I stepped on the brake a couple times, as those pedals are too close together and I have wide feet. My reaction was to instantly move my foot. A number of those "surging" incidents are suspected of being the driver had their foot on the gas rather than the brake. Glad to hear you're all right after the crash. I nearly died in a car crash. Sorry to hear about your dad. It must be very frustrating to not know the cause. I thought all GA accidents were officially investigated.
      - genewitch 1y ago
        My car has a pushbutton "ignition switch" and i have not tried pushing it while travelling; however, my lexus also has floormat retention to stop the floormat from going onto the gas pedal. It wasn't "accidental" - there was a recall. The toyotas and lexus affected don't have a floating accelerator pedal, where it hangs from above and there's space underneath. The gas pedal is hinged on the floor, and swings free at the top. So you could shove something forward and it will push the gas pedal down. If memory serves there was an instance in southern california where the driver called 911 or some other recorded line (they died); but it may have just been a witness statement i remember.

throwaway5752 1y ago

I see in a sibling comment that you do not think the MCAS system on the MAX was well designed, and the reliance on a single AoA sensor was not a good decision. I agree. The aircraft should have never been declared airworthy. There should have been no need for an EAD in the first place. There is no excuse for putting a control system that flies the craft into the ground when there is a failure in a nonredundant sensor on a commercial aircraft. The high standards required for pilots, like Amelia Earhart, do not obviate the even higher standards for quality and safety from manufacturers.

WalterBright 1y ago
I suspect that Boeing didn't think it would be a problem because the runaway stab trim procedure is enough to stop it and recover. Who would have thought that trained pilots would not remember this procedure? It's supposed to be a "memory item", meaning consulting the checklist was not required. The stab trim cutoff switch is in a prominent position on the central console (not overhead or behind the crew). In the first Lion Air crash, the airplane dipped and recovered (via the thumb switches) 25 times over a period of 11 minutes. They never thought to turn off the stab trim system. It boggles the mind. Would you want to fly with a crew that didn't know what the switches on the console were for? Not me. Both Boeing and the crew are at fault. Some percentage also for whoever made the faulty sensor and the failure to see that it worked correctly after it was installed.
- genewitch 1y ago
  Do we also blame the drivers of the Toyotas that got stuck accelerators, because any driver should know to take the car out of gear or turn the key to the off position. Right? While the car is accelerating at or near WOT? I've been in a car when the throttle got stuck open, we crashed, I hit the windshield. It happened in about 5 seconds, and the driver spent most of those giving steering inputs to avoid hitting people and furiously working the break and kicking the gas pedal. It happened because enough engine mounts were broken or broke because of a hard throttle push. Also my dad died in a single seat plane crash because the engine died several times in flight, according to a witness interviewed by a local paper; there was no investigation at all so I'll never know what really happened. At least the company that made the plane changed their name!
  - WalterBright 1y ago
    I had the throttle stick on my car once. I immediately turned the ignition off. I was a teenager at the time (and my car was a POS). The brakes are much stronger than the engine (proof: you can brake in a much shorter distance than you can accelerate). On my current car, I have inadvertently hit the edge of the gas pedal while I stepped on the brake a couple times, as those pedals are too close together and I have wide feet. My reaction was to instantly move my foot. A number of those "surging" incidents are suspected of being the driver had their foot on the gas rather than the brake. Glad to hear you're all right after the crash. I nearly died in a car crash. Sorry to hear about your dad. It must be very frustrating to not know the cause. I thought all GA accidents were officially investigated.
    - genewitch 1y ago
      My car has a pushbutton "ignition switch" and i have not tried pushing it while travelling; however, my lexus also has floormat retention to stop the floormat from going onto the gas pedal. It wasn't "accidental" - there was a recall. The toyotas and lexus affected don't have a floating accelerator pedal, where it hangs from above and there's space underneath. The gas pedal is hinged on the floor, and swings free at the top. So you could shove something forward and it will push the gas pedal down. If memory serves there was an instance in southern california where the driver called 911 or some other recorded line (they died); but it may have just been a witness statement i remember.