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What Really Brought Down the Boeing 737 Max?

nytimes.com

31–40 of 44 posts

Re: What Really Brought Down the Boeing 737 Max?

#31
post #30

Can someone validate my thinking here, please? I’ve been watching this saga for a while and there is something that doesn’t seem to be said that really bothers me about this whole situation: the failure mode is negative, not neutral. Here is what I mean. An aircraft has a flight envelop that defines its flight characteristics. Not only does it define in how fast or slow or high it can operate, but how that operation…

Yes.

You are absolutely, 100% on the money. Got it in one.

The entire MCAS fiasco was born out of deadlines and deliveries at at all costs, sound engineering be damned.

The entire thing was very specifically orchestrated in such a way as to minimize the chances that any external authorities or pilots would ask any inconvenient questions.

Re: What Really Brought Down the Boeing 737 Max?

#32
>>Immediately after liftoff, the captain’s airspeed indication failed, airspeed-disagreement and altitude-disagreement warnings appeared on his flight display and his stick shaker began to rattle the controls in warning of an imminent stall.

This simple fact has simply been ignored by the broder community on hackernews who are not pilots. The airspeed indicator is tied into the AoA sensor. The moment the AoA fails the pilots recieve an airspeed disagreement warning that must be fixed using the unreliable airspeed checklist. If your analysis of what happend on either of the accident flight ignores this critical fact you are wrong.

Welcome to the Danning-Krueger effect in action

Re: What Really Brought Down the Boeing 737 Max?

#33

Wow, such a long article in what probably could be condensed into 1 a4 sized page if you really are just about answering the question posed. Who actually reads articles like this? I am genuinely curious. Comes off as information overload to me and it's hard to know what to believe.

I do. William Langewiesche is probably the best writer on aviation - if you want really deep and detailed analysis.

I don't consider it analysis. It is a discussion. He writes that Air France 447 was "an exercise in poor airmanship", full stop. That is completely inconsistent with the final report on AF 447, where literally everyone but the passengers got part of the blame for it. It blamed Air France, it blamed Airbus, it blamed the simulators, it blamed the pilots.

His central thesis in this article might be:

Boeing became the world’s pre-eminent commercial airplane manufacturer in part because it developed a coherent design philosophy that relied on pilots’ airmanship as the last line of defense.

And that's come up before in various discussions like Langewiesche's. And here I'll underscore this article is a discussion, it's not an analysis. He does bring in myriad relevant factors like airline's being cheap, foolhardy, downright wreckless at times, literally expecting pilots to paper over their decisions. I think that is a real problem all airlines have to contend with, but the safest airlines have mostly solved it, and the least safe airlines still struggle with it and it's mostly about systemic corruption, not pilot incompetency. It's just that if you don't have particularly skilled and experienced pilots all of the time, you're playing roulette - you don't have your last line of defense all of the time. Eventually, things aren't going to work out well. And on that part of the discussion, I agree with him.

Re: What Really Brought Down the Boeing 737 Max?

#34

>>Immediately after liftoff, the captain’s airspeed indication failed, airspeed-disagreement and altitude-disagreement warnings appeared on his flight display and his stick shaker began to rattle the controls in warning of an imminent stall. This simple fact has simply been ignored by the broder community on hackernews who are not pilots. The airspeed indicator is tied into the AoA sensor. The moment the AoA fails th…

What in the unreliable airspeed checklist would have saved the flight?

Once mistrim happens, there is no possible way to get either of the two flights in question, to either 4 degrees pitch up and 75% N1, let alone 10 degrees pitch up and 80% N1. Any power reduction will cause a pitch down and make the problem worse. All your advise would do is kill them faster. Mistrim must be avoided at low altitude, and in these two cases MCAS induced mistrim faster than it could be identified and avoided. It takes significant altitude to recover from it, assuming you even know the procedure, which hasn't been in the 737 FOM for decades. Neither flight had sufficient altitude for that procedure.

If all of this were just about training and checklists, these airplanes wouldn't be grounded around the world.

I also find it hilarious you misspell your insult.

Re: What Really Brought Down the Boeing 737 Max?

#35

Finally, one lone voice cuts through the hysteria and garbage and speaks the unpopular truth. The good old boy culture of training men inadequately so that they can, at best, monitor an aircraft's systems, and then pretending that they are pilots is what killed those people. You don't like it, but it's the truth.

FTA: "another of Boeing’s bewildering failures" he refers to the MCAS implementation as "throwing the airplane wildly out of trim" and "No one I spoke to from Boeing, Airbus or the N.T.S.B. could explain the reasoning here."

You are trying to hold pilots accountable in some vague sense, so what of holding Boeing and the FAA accountable in a non-vague sense? How is the actual delivered form of MCAS reasonable? How do you expect, given available factual flight data from both flights, MCAS induced mistrim to be avoided? Do you agree that it must be avoided at the low altitudes both of these flights were at, because it's not possible to recover from mistrim at low altitude?

If this were just about pilot training and certification, why are these airplanes grounded around the world? You really think the problem is just with a handful of "3rd world" pilots? Do you even realize that the Ethiopian Airlines pilot was one of their most experienced, and this experience as a fighter pilot is demonstrated in his recovery attempts shown in the flight data?

I mean, it's almost like some people don't know what they're talking about, yet call their nonsensical prattle "the truth" because they enjoy trying to aggravate thinking people, quite possibly the only actual skill they have.

Re: What Really Brought Down the Boeing 737 Max?

#36

Earlier quoted context omitted.

I do. William Langewiesche is probably the best writer on aviation - if you want really deep and detailed analysis.

Cool, you must honestly be one of a few. I could never bear myself to read such a long article even if the topic was of interest. I can listen to or view content that are hours long but in text format it's kind of overwhelming to me. Mainly because I cannot do anything else than read while I am reading which makes reading such a piece a very time-consuming task. I'd rather do something else than read such an article…

I understand your point, but I read articles like this (and especially ones by Langewiesche) because there are topics that, for me, I learn better about it this way. I'm exactly opposite of you -- I generally can't bear to watch videos or listen to podcasts about these kinds of nonfiction topics because they feel way too long to me, whereas I can read an article faster and skip the parts easily that I don't feel are good.

Re: What Really Brought Down the Boeing 737 Max?

#38
I think it was the first article I've read on the issue that actually explained all the factors in a clear way. As it's a complicated issue it needed to be long. Even though the pilots evidently were incompetent, I do think he's too light on his criticism against Boeing. The failure mode on this system was too drastic, and unnecessarily persistent. Combined with the fact that all that was needed was one faulty sensor this was obviously shoddy engineering.

Re: What Really Brought Down the Boeing 737 Max?

#39
post #29

Finally, one lone voice cuts through the hysteria and garbage and speaks the unpopular truth. The good old boy culture of training men inadequately so that they can, at best, monitor an aircraft's systems, and then pretending that they are pilots is what killed those people. You don't like it, but it's the truth.

No... Not really. I mean, I agree with you to a point. There is a delight taken by manufacturers being able to ostensibly cut training costs. But in this case, the fact was the plane itself was unsoundly engineered. Even highly skilled pilots have failed to rescue the plane in a simulator. The pilot cannot be the primary carrier of blame when the equipment in the best hands available had only a 66% chance of having t…

You wrote "Even highly skilled pilots have failed to rescue the plane in a simulator".

This is utter nonsense that you either made up or obtained from some unreliable source. It is categorically false.

The third pilot in the jump seat "rescued" the Lion Air accident aircraft on the previous flight by simply telling the pilots to disengage the stabilizer trim. This "rescued" aircraft continued 600 miles safely to Jakarta.

You know nothing and yet you have opinions, and this is now universally accepted. You are therefore easily manipulated by those who would blame Boeing instead of the gross and egregious negligence of the pilots, those who trained them, the airline owners and executives, and the market conditions that forced Boeing to make decisions in good faith that incorrectly assumed a level of pilot competency that did not exist.

In the words of the Air France 447 pilot just before he died from his own gross incompetence, “[Expletive], we’re dead.” And in this, I am referring to the human species.

Re: What Really Brought Down the Boeing 737 Max?

#40

The author has done a great deal of thoughtful investigative work and that's always a good thing. However, in his attempt to reach conclusions and assign blame he has diluted the effectiveness of the article. I'm very interested in this topic, so I skimmed through it (a very long read) and get a sense of whether it's worth further study. I decided to move on.

Exactly. It reads like an attempt to validate a foregone conclusion using components of thorough investigation. The author threw in a few gratuitous statements about how "maybe MCAS wasn't the best idea" so that the they couldn't really be accused of blindly supporting Boeing.

It sounds like Lion Air were victims of not knowing the systems in place. Ethiopian Air didn't seem to have the altitude to figure things out in a timely manner.

This isn't to say that there's not corruption and other things going sideways in these investigations, but to lay blame squarely on the countries and the airlines is really disingenuous.

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