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It is not acceptable that pilots were unaware of the cutoff switches. It is unacceptable that MAX pilots did not read, understand, and remember the Airworthines

It is not acceptable that pilots were unaware of the cutoff switches. It is unacceptable that MAX pilots did not read, understand, and remember the Airworthiness Directive sent to all MAX crews. The Ethiopian crew tried the cutout switches and found they couldn't trim the airplane with the hand cranks because Boeing lied. How is that a pilot training issue? But there were other contributing factors in the crashes that must be dealt with. A Boeing employee concern trolling over pilot training is pretty rich considering that Boeing knowingly hid crucial details from pilots.

WalterBright 7y ago
> The Ethiopian crew tried the cutout switches and found they couldn't trim the airplane with the hand cranks because Boeing lied. How is that a pilot training issue? The Emergency Airworthiness Directive to all MAX crews says: "Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT." https://theaircurrent.com/wp-content/uploads/2018/11/B737-MAX-AD-1107.pdf https://theaircurrent.com/wp-content/uploads/2018/11/B737-MA... > A Boeing employee I left Boeing about 40 years ago.
- inferiorhuman 7y ago
  Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT. If the graphs are to be believed neither the electric commands nor hand crank were able to move the stabilizer. Again, how is that a pilot training issue?
  - WalterBright 7y ago
    I don't know what graph you're looking at. The reports I saw was that the EA pilots did not follow the procedure: 1. trim to normal with the electric trim switches 2. cut off the stabilizer trim What the EA pilots did was: 1. cut off the stabilizer trim 2. try to use the hand cranks to trim to normal
    - inferiorhuman 7y ago
      I don't know what graph you're looking at. Graphs of the FDR data from the (preliminary) accident reports. The Ethiopian authorities even annotated theirs with things like "automatic trim command with no change in pitch trim". You can see quite plainly the stabilizer was not moving as intended. 2. try to use the hand cranks to trim to normal Per Boeing's documentation this should've worked. Unfortunately Boeing's documentation is mostly wishful thinking. Boeing's also suggested that a pilot try unloading the stabilizer with a roller coaster type maneuver. Unfortunately Boeing removed detailed instructions on this maneuver decades ago and the FAA's already demonstrated that with the altitude that the Ethiopian crew had, unloading the stabilizer would've just flown the plane into the ground. There's a reason Boeing's largely backed off of the whole pilot error nonsense: the 737 MAX crashed due to shitty design not pilot error.

WalterBright 7y ago

> The Ethiopian crew tried the cutout switches and found they couldn't trim the airplane with the hand cranks because Boeing lied. How is that a pilot training issue? The Emergency Airworthiness Directive to all MAX crews says: "Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT." https://theaircurrent.com/wp-content/uploads/2018/11/B737-MAX-AD-1107.pdf https://theaircurrent.com/wp-content/uploads/2018/11/B737-MA... > A Boeing employee I left Boeing about 40 years ago.

inferiorhuman 7y ago
Initially, higher control forces may be needed to overcome any stabilizer nose down trim already applied. Electric stabilizer trim can be used to neutralize control column pitch forces before moving the STAB TRIM CUTOUT switches to CUTOUT. Manual stabilizer trim can be used before and after the STAB TRIM CUTOUT switches are moved to CUTOUT. If the graphs are to be believed neither the electric commands nor hand crank were able to move the stabilizer. Again, how is that a pilot training issue?
- WalterBright 7y ago
  I don't know what graph you're looking at. The reports I saw was that the EA pilots did not follow the procedure: 1. trim to normal with the electric trim switches 2. cut off the stabilizer trim What the EA pilots did was: 1. cut off the stabilizer trim 2. try to use the hand cranks to trim to normal
  - inferiorhuman 7y ago
    I don't know what graph you're looking at. Graphs of the FDR data from the (preliminary) accident reports. The Ethiopian authorities even annotated theirs with things like "automatic trim command with no change in pitch trim". You can see quite plainly the stabilizer was not moving as intended. 2. try to use the hand cranks to trim to normal Per Boeing's documentation this should've worked. Unfortunately Boeing's documentation is mostly wishful thinking. Boeing's also suggested that a pilot try unloading the stabilizer with a roller coaster type maneuver. Unfortunately Boeing removed detailed instructions on this maneuver decades ago and the FAA's already demonstrated that with the altitude that the Ethiopian crew had, unloading the stabilizer would've just flown the plane into the ground. There's a reason Boeing's largely backed off of the whole pilot error nonsense: the 737 MAX crashed due to shitty design not pilot error.