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Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

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Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#111
post #15

It's now fairly obvious MCAS was at the root of those two crashes. But, did it save lives in other circumstances? Meaning, was there ever a case where the nose went up so much, because of the bigger motors and their different location on the wings, that the activation of MCAS prevented a stall? I'm surprised no one seems to talk about this. It's also surprising the MCAS was implemented at all, instead of an alarm. Ye…

As far as I know, MCAS has never activated in service due to actual high AoA. However, even the 737 classic could have "interesting" pitch up characteristics: "The Boeing 737-300 was on approach to Bournemouth Airport following a routine passenger flight from Faro, Portugal. Early in the ILS approach the auto-throttle disengaged with the thrust levers in the idle thrust position. The disengagement was neither command…

MCAS wouldn't have been active since the flaps were down.

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#112
post #77

Earlier quoted context omitted.

The main thing for me is that NOW pilots will be aware that there is a piece of software running in the background that might fight them. The first thing they will all learn is how to disable it so they can actually fly the airplane. That's even without a software fix. To me, it all comes down to to Boeing being able to self-certify their aircraft, and they knew they were sneaking the "fix" known as MCAS as a way to…

The reason this preliminary report is so damning is that it's evident that the pilots on flight 302 knew this - they realised what was happening, took the necessary steps to disable MCAS, and still couldn't stop the plane from crashing and killing everyone on board.

Read the narrative in the report. Why do you suppose that after they got the same initial signs of trouble that the Lion Air flight had (stick shaker on left side, disagreement in airspeed values, etc. immediately after takeoff) that the captain tried to engage autopilot and instructed the first officer to retract flaps and inform controllers they were proceeding to climb to FL 320 (32,000 ft). Why not instead turn back and land and hand the aircraft over to maintenance?

From the report:

At 05:38:44, shortly after liftoff, the left and right recorded AOA values deviated. Left AOA decreased to 11.1° then increased to 35.7° while value of right AOA indicated 14.94°. Then after, the left AOA value reached 74.5° in ¾ seconds while the right AOA reached a maximum value of 15.3°. At this time, the left stick shaker activated and remained active until near the end of the recording. Also, the airspeed, altitude and flight director pitch bar values from the left side noted deviating from the corresponding right side values. The left side values were lower than the right side values until near the end of the recording.

...

At 05:39:06, the Captain advised the First-Officer to contact radar and First Officer reported SHALA 2A departure crossing 8400 ft and climbing FL 320.

...

At 05:39:42, Level Change mode was engaged. The selected altitude was 32000 ft. Shortly after the mode change, the selected airspeed was set to 238 kt.

At 05:39:45, Captain requested flaps up and First-Officer acknowledged. One second later, flap handle moved from 5 to 0 degrees and flaps retraction began.

Bear in mind stick shaker and divergent instrument readings all this time.

Why not just return and land, leave the flaps configuration alone (which would have inhibited MCAS), especially since this is exactly how the Lion Air flight started.

I know this is easy to critique from the comfort of my chair, and the pilots are not here to defend themselves, but some things in this narrative just don't make sense.

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#113
post #89
post #77

Earlier quoted context omitted.

The reason this preliminary report is so damning is that it's evident that the pilots on flight 302 knew this - they realised what was happening, took the necessary steps to disable MCAS, and still couldn't stop the plane from crashing and killing everyone on board.

The took the necessary steps and it was working until they went off script. Whether or not their hand was force because the script stopped working remains to be seen. IMHO, there's little to do except to wait for the full report to come out. The speculation about the crash was wildly wrong and the preliminary report coming out didn't really stop that.

Why are you speaking authoritatively about what the pilot's did and in the same breath admonishing people for not waiting for the "full report"?

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#114
post #108

Earlier quoted context omitted.

> The took the necessary steps and it was working until they went off script. Whether or not their hand was force because the script stopped working remains to be seen The script required them to manually crank in the stabilizer, which wasn't possible. The script was manifestly not "working". That doesn't "remain to be seen" -- it's in the transcript of the cockpit

Yes, people are speculating this and like the previous speculation they're probably wrong.

> At 05:40:35, the First-Officer called out “stab trim cut-out” two times. Captain agreed and First- Officer confirmed stab trim cut-out.

> At 05:41:46, the Captain asked the First-Officer if the trim is functional. The First-Officer has replied that the trim was not working and asked if he could try it manually. The Captain told him to try. At 05:41:54, the First-Officer replied that it is not working.

I guess the First-Officer must have been speculating...

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#115

I know better than to read between the lines on a press release like this, but can't help but notice that it falls far short of accepting responsibility for the problem. He admits that MCAS "activated in response to erroneous angle of attack information" but doesn't admit that this alone directly resulted in the crashes. Rather, he implies that this sets off a chain of events which the pilots are unable to deal with…

I agree. They certainly stopped short of exonerating the pilots, and the airlines.

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#116
post #89

Earlier quoted context omitted.

The took the necessary steps and it was working until they went off script. Whether or not their hand was force because the script stopped working remains to be seen. IMHO, there's little to do except to wait for the full report to come out. The speculation about the crash was wildly wrong and the preliminary report coming out didn't really stop that.

Why are you speaking authoritatively about what the pilot's did and in the same breath admonishing people for not waiting for the "full report"?

Because the preliminary report contains data showing that electric trim was re-engaged.

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#117
The root problem seems to be FAA not having qualified engineers to thoroughly test the planes Boeing makes. Boeing pays better, so it hires the best engineers. FAA pays less so it gets second-grade engineers. And we all pay by flying in unsafe planes.

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#118
this is just a total saving face scenario. he even mentions that after the lion air flight they knew about this (i would claim they knew about it long before that anyway) and have been working on a fix. then why the cold response still after the ethiopian airlines crash?

furthermore, this is summed up by just "we'll fix it in software". hurray, everything we touch including cars and airplanes are now subscribing to the "we'll fix it in software" approach. failed a safety brake test? fix it with software. kill a few hundred people by an automatic system crashing a plane? fix it with software.

i really hope society wakes up and SLOWS DOWN. we're trying to move so fast, with hardly any reason at all, and in doing so, we are throwing away all ability to properly design, build, and god forbid, think about things. i don't know what it's going to take, but it feels out of control. everywhere you look is people hurrying and hurrying to release, to productize, to ship it, etc. whenever i ask "why?" to schedules, there has NEVER been a clear answer. it always boils down to basically "just because".

in addition, we simply have too much laziness and greed taking place, which is what added to boeing's misstep here. they tried pulling a fast one on buyers (and basically accomplished it) to make a few bucks towards that everlasting capitalist dream.

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#119
post #116

Earlier quoted context omitted.

Why are you speaking authoritatively about what the pilot's did and in the same breath admonishing people for not waiting for the "full report"?

Because the preliminary report contains data showing that electric trim was re-engaged.

Why are you dismissing the data the report contains indicating that the flight crew was unable to trim manually, that the column forces were incredibly high, and that the captain repeatedly indicated he could not maintain elevator trim without the co-pilot's aid, then?

Your responses have been incredibly selective about which parts of the report you take as gospel and which you handwave away as "speculation".

From where I'm sitting it appears you've started out by picking a contrarian conclusion you like ("the plane was safe once STAB CUTOUT was set cutout, and the crew could have maintained altitude indefinitely at that point, but fatally fucked up by re-engaging electronic trim to try to trim the stabilizer"), and to maintain that a priori conclusion you've consistently ignored the data and parts of the transcript that indicate that was very likely impossible.

Re: Boeing CEO Dennis Muilenburg Addresses the Ethiopian Airlines Flight 302 Report

#120
post #117

The root problem seems to be FAA not having qualified engineers to thoroughly test the planes Boeing makes. Boeing pays better, so it hires the best engineers. FAA pays less so it gets second-grade engineers. And we all pay by flying in unsafe planes.

Following your line of reasoning, wouldn't the supposedly better engineers build more safe planes, relegating the poor dunces to only validating the designs from their intellectual superiors? In your hypothetical, they aren't paying more for safety dodgers.
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