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I find that there's bit of irony in you of all people defending a safety-critical system that can kill hundreds of people if human error occurs during a high-st

I find that there's bit of irony in you of all people defending a safety-critical system that can kill hundreds of people if human error occurs during a high-stress situation. The way I understand it, the pilots only had less than twenty seconds to perform the two steps you refer to; that's fine if they've been specifically trained to perform these steps enough times that they become second nature, but the very point of the MCAS system was that Boeing didn't want clients to pay for additional training. In a high-intensity situation, when the aircraft does something unexpected and the pilots have no time to consult the manual, it's really easy to forget one bit of the manual if it hasn't been drilled into you.

WalterBright 6y ago
> the pilots only had less than twenty seconds to perform the two steps you refer to; The LA crew battled it for 5-6 minutes, bringing the trim back to normal with the electric trim switches 25 times. All they had to do was then turn the cutoff switches. The EA crew for a couple minutes, bringing the trim back to normal twice. The trim activated again, and this time they turned off the trim while the stab was hard over. I.e. they performed the steps backwards. > the pilots have no time to consult the manual This is why stab trim runaway is a "memory item". They're supposed to have it memorized. It's not complex, either. It's bring the trim back to normal, then turn it off. > if it hasn't been drilled into you Being a memory item means it's supposed to be drilled into you. > the very point of the MCAS system was that Boeing didn't want clients to pay for additional training Stab trim runaway procedure is the same regardless of MCAS causing it or some other reason with the older 737. > defending a safety-critical system I'm emphatically not defending a safety-critical system that was far too susceptible to failure. I'm saying that the MCAS failures were recoverable by a crew that followed runaway trim procedure. This is especially true for the EA crew that received an Emergency Airworthiness Directive that laid out the two step process. Consider an analogous situation. An airplane catches fire. This is NEVER EVER EVER supposed to happen. Even so, the airplane has fire extinguishers aboard and procedures for dealing with fire. I expect crews to be trained in how to deal with the fire, and to be proficient at it. Every accident has multiple causes. All of them need to be addressed to make flying safe.
- PoignardAzur 6y ago
  Fair enough. This isn't the way I saw it presented before.

WalterBright 6y ago

> the pilots only had less than twenty seconds to perform the two steps you refer to; The LA crew battled it for 5-6 minutes, bringing the trim back to normal with the electric trim switches 25 times. All they had to do was then turn the cutoff switches. The EA crew for a couple minutes, bringing the trim back to normal twice. The trim activated again, and this time they turned off the trim while the stab was hard over. I.e. they performed the steps backwards. > the pilots have no time to consult the manual This is why stab trim runaway is a "memory item". They're supposed to have it memorized. It's not complex, either. It's bring the trim back to normal, then turn it off. > if it hasn't been drilled into you Being a memory item means it's supposed to be drilled into you. > the very point of the MCAS system was that Boeing didn't want clients to pay for additional training Stab trim runaway procedure is the same regardless of MCAS causing it or some other reason with the older 737. > defending a safety-critical system I'm emphatically not defending a safety-critical system that was far too susceptible to failure. I'm saying that the MCAS failures were recoverable by a crew that followed runaway trim procedure. This is especially true for the EA crew that received an Emergency Airworthiness Directive that laid out the two step process. Consider an analogous situation. An airplane catches fire. This is NEVER EVER EVER supposed to happen. Even so, the airplane has fire extinguishers aboard and procedures for dealing with fire. I expect crews to be trained in how to deal with the fire, and to be proficient at it. Every accident has multiple causes. All of them need to be addressed to make flying safe.

PoignardAzur 6y ago
Fair enough. This isn't the way I saw it presented before.