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Boeing were idiots selling this new model into the markets they did right out the gate. It was greed and bit them hard. Poor maintenance. Pilot skills in hand

Boeing were idiots selling this new model into the markets they did right out the gate. It was greed and bit them hard. Poor maintenance. Pilot skills in hand flying and unusual flying and recovery so different (overseas they don't always come through a normal US style GA background). If they would have looked more closely at the US, they would have found that this system was triggered (and resolved) I suspect pretty frequently by US pilots - ie, the pilots in the loop compensated for the design weaknesses which was the boeing thinking historically. US pilots have played that role on many planes, usually mfg then fixes the issues as well. If they are going to continue to sell internationally in the markets they want to they actually need to think about doing more automation and flight protection stuff - more computers - not less. This may never have been the major issue it became if they had focused on a major carrier like Southwest (very experienced crews). The whole MCAS thing was garbage, interesting they are pinning it on this guy. He does say internally he lied to FAA (unknowingly) as they weren't fully familiar with MCAS modes and edge Edit: Appears I was wrong - good maintenance in US seems to have been key saving thing. "Following the recent events in Indonesia and Ethiopia, U.S. flight data was analyzed to understand whether indicators may have existed that could have been addressed, and potentially preempted the accidents. The data showed zero incidents of runaway trim on Boeing 737 MAX 8 aircraft in the U.S. system,” says the report from the special committee. Good job A&P folks!

deleted 5y ago
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evilos 5y ago
The people that really got bitten are the ones that died on impact :(
WalterBright 5y ago
The flight previous to the LA crash also experienced the MCAS malfunction. You don't hear about that one because the crew used the electric trim switches to return trim to normal, then turned off the stab trim system with the cutoff switches. Then, they continued the flight and landed normally. The next flight on the same airplane is the one that crashed. The crew restored normal trim with the electric trim switches 25 times, but never shut off the trim system. The EA crew also restored normal trim with the trim switches, but then turned off the trim when the stabilizer was too far nose down. This is contrary to the instructions in the Boeing Emergency Airworthiness Directive distributed to all MAX pilots. This does not absolve Boeing's role in not doing a proper failure analysis of the MCAS system. But contrary to what Frontline said "the pilots did everything right" it was recoverable if the instructions for runaway trim were followed.
- ummonk 5y ago
  The Ethiopian Airlines pilots followed the EAD to the letter. First, they attempted to adjust trim using electric stabilizer trim, and then upon realizing that the they were experiencing an uncommanded nose down stabilizer trim, they followed the runaway stabilizer procedure - namely, stab trim cutout and trim wheel grasp and hold. Afterwards, they attempted to adjust the stabilizer manually. There is a note in the EAD that electric stabilizer trim can be used to neutralize the stabilizers before doing a stab trim cutout, but crucially Boeing did not instruct pilots to make sure to neutralize trim first using electric trim before doing the stab trim cutout.
  - WalterBright 5y ago
    > Boeing did not instruct pilots to make sure to neutralize trim first using electric trim before doing the stab trim cutout. Yes, they did: "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... Note also that the EA pilots had already successfully overridden and restored normal trim twice with the electric trim switches. (I added the emphasis on "before".)
    - ummonk 5y ago
      That's not an instruction - it's a digression. The wording there is "can be used". The actual instruction is to follow the AFM Runaway Stabilizer procedure. That's exactly what the Ethiopian Airlines pilots did.
      - WalterBright 5y ago
        > That's not an instruction - it's a digression. The wording there is "can be used". Why do you think Boeing wrote an EMERGENCY AIRWORTHINESS DIRECTIVE and the FAA mandated it be sent to all MAX pilots? If you're a pilot, it is YOUR JOB to read, understand, and remember every EMERGENCY AIRWORTHINESS DIRECTIVE. Not to parse words. If you want to parse words, get a job as a lawyer, not a pilot. The "can be used" is there to explain how to overcome aerodynamic forces that make using the manual trim wheel difficult.
dboreham 5y ago
>Pilot skills in hand flying and unusual flying and recovery so different (overseas they don't always come through a normal US style GA background). This is repeating lies propagated by Boeing management and is not true. The flight control system's design was flawed. It was a "fly into the ground sometimes" machine.
ummonk 5y ago
There was actually a test with Southwest Airlines line pilots, and it took them a minute to get to the stab trim cutout in response to this issue. https://www.commerce.senate.gov/services/files/3BBE2CD5-AE41-4048-9C50-DC7B59D644CB https://www.commerce.senate.gov/services/files/3BBE2CD5-AE41... The Ethiopian Airlines pilots did get to the stab trim cutout as well (probably because they had read the emergency directive Boeing sent out) but were unable to manually trim afterwards due to the forces involved - had they cut airspeed at the start they probably would have been able to do so, but that was not part of the instructions at the time. For an analysis of the situation they were in, see https://leehamnews.com/2019/04/05/bjorns-corner-et302-crash-report-the-first-analysis/ https://leehamnews.com/2019/04/05/bjorns-corner-et302-crash-...

deleted 5y ago

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evilos 5y ago

The people that really got bitten are the ones that died on impact :(

WalterBright 5y ago

The flight previous to the LA crash also experienced the MCAS malfunction. You don't hear about that one because the crew used the electric trim switches to return trim to normal, then turned off the stab trim system with the cutoff switches. Then, they continued the flight and landed normally. The next flight on the same airplane is the one that crashed. The crew restored normal trim with the electric trim switches 25 times, but never shut off the trim system. The EA crew also restored normal trim with the trim switches, but then turned off the trim when the stabilizer was too far nose down. This is contrary to the instructions in the Boeing Emergency Airworthiness Directive distributed to all MAX pilots. This does not absolve Boeing's role in not doing a proper failure analysis of the MCAS system. But contrary to what Frontline said "the pilots did everything right" it was recoverable if the instructions for runaway trim were followed.

ummonk 5y ago
The Ethiopian Airlines pilots followed the EAD to the letter. First, they attempted to adjust trim using electric stabilizer trim, and then upon realizing that the they were experiencing an uncommanded nose down stabilizer trim, they followed the runaway stabilizer procedure - namely, stab trim cutout and trim wheel grasp and hold. Afterwards, they attempted to adjust the stabilizer manually. There is a note in the EAD that electric stabilizer trim can be used to neutralize the stabilizers before doing a stab trim cutout, but crucially Boeing did not instruct pilots to make sure to neutralize trim first using electric trim before doing the stab trim cutout.
- WalterBright 5y ago
  > Boeing did not instruct pilots to make sure to neutralize trim first using electric trim before doing the stab trim cutout. Yes, they did: "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... Note also that the EA pilots had already successfully overridden and restored normal trim twice with the electric trim switches. (I added the emphasis on "before".)
  - ummonk 5y ago
    That's not an instruction - it's a digression. The wording there is "can be used". The actual instruction is to follow the AFM Runaway Stabilizer procedure. That's exactly what the Ethiopian Airlines pilots did.
    - WalterBright 5y ago
      > That's not an instruction - it's a digression. The wording there is "can be used". Why do you think Boeing wrote an EMERGENCY AIRWORTHINESS DIRECTIVE and the FAA mandated it be sent to all MAX pilots? If you're a pilot, it is YOUR JOB to read, understand, and remember every EMERGENCY AIRWORTHINESS DIRECTIVE. Not to parse words. If you want to parse words, get a job as a lawyer, not a pilot. The "can be used" is there to explain how to overcome aerodynamic forces that make using the manual trim wheel difficult.

dboreham 5y ago

>Pilot skills in hand flying and unusual flying and recovery so different (overseas they don't always come through a normal US style GA background). This is repeating lies propagated by Boeing management and is not true. The flight control system's design was flawed. It was a "fly into the ground sometimes" machine.

ummonk 5y ago

There was actually a test with Southwest Airlines line pilots, and it took them a minute to get to the stab trim cutout in response to this issue. https://www.commerce.senate.gov/services/files/3BBE2CD5-AE41-4048-9C50-DC7B59D644CB https://www.commerce.senate.gov/services/files/3BBE2CD5-AE41... The Ethiopian Airlines pilots did get to the stab trim cutout as well (probably because they had read the emergency directive Boeing sent out) but were unable to manually trim afterwards due to the forces involved - had they cut airspeed at the start they probably would have been able to do so, but that was not part of the instructions at the time. For an analysis of the situation they were in, see https://leehamnews.com/2019/04/05/bjorns-corner-et302-crash-report-the-first-analysis/ https://leehamnews.com/2019/04/05/bjorns-corner-et302-crash-...