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US refuses to ground Boeing 737 Max

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Re: US refuses to ground Boeing 737 Max

#271

Post by sokoloff »

kalleboo wrote: post #51
prostoalex wrote: post #24

Earlier quoted context omitted.

While you may end up being entirely correct, it is too early to start finger-pointing before the investigations are finished. Neither Lion nor Ethiopian had stellar safety records, e.g. * https://www.nytimes.com/2018/11/22/world/asia/lion-air-crash... * https://en.wikipedia.org/wiki/Ethiopian_Airlines_accidents_a... The training hours should also be looked in the context of the total hours flown on that specific mode…

> It's not like Boeing took a freshly minted Cessna 152 pilot, gave them a 2-hour seminar, and type-rated them for the 737 Max This ASRS report almost makes it sound like that https://news.ycombinator.com/item?id=19374386

The author of that ASRS report almost surely holds an ATP, a 737 type rating, and has passed the -MAX differences training.

That's quite a stretch from a 4-cylinder single engine, 110mph prop plane transition.

Re: US refuses to ground Boeing 737 Max

#272

Post by dsfyu404ed »

AsyncAwait wrote: post #231
dsfyu404ed wrote: post #199

Earlier quoted context omitted.

I would consider pilots not being made sufficiently aware of the implications of a faulty AoA sensor a maintenance failure. Clearly people have fucked up because planes have crashed. We're basically just arguing over whether the responsibility split goes 33/33/33 or 20/20/60 or something else.

> I would consider pilots not being made sufficiently aware of the implications of a faulty AoA sensor a maintenance failure. From what others have said, I gather there is a problem of this plane behaving differently than the rest of the family, which is being 'masked' by the on-board software so that it 'feels' similar to the other planes in a regular situation and thus requires minimal additional training. This how…

>From what others have said, I gather there is a problem of this plane behaving differently than the rest of the family, which is being 'masked' by the on-board software so that it 'feels' similar to the other planes in a regular situation and thus requires minimal additional training

The problem that's (presumably) causing crashes isn't how the plane flies. It's perfectly flyable but has a tendency to pitch up more than other planes of the type. As a response, Boeing added functionality to MCAS to compensate.

The first crash likely wouldn't have happened had the pilots turned all the electronic nannies off and flown raw dog. The just didn't realize that was what they had to do for a combination of reasons.

Not knowing that they were flying with a screwy AoA sensor and what the symptoms of that would look like is a maintenance/communication/human systems failure.

The fact that a faulty AoA sensor can have those symptoms and the fact that the pilots didn't know about it well enough to make the connection themselves and disable the system is a failure on Boeing.

Think of it like having a crossover that wanders more than the comparable sedan at highway speed so the OEM silently turns on lane keeping when you use cruise control to compensate. There's a risk that if you're not paying attention it will find a lane that isn't a lane and drive you into a barrier at 70 and on this particular one the relevant sensor was faulty and more prone to doing that.

Re: US refuses to ground Boeing 737 Max

#273

Post by darkcha0s »

julianlam wrote: post #263
Recurecur wrote: post #259

Earlier quoted context omitted.

If it was a "similar cause", it is absolutely pilot error. The MCAS system, at fault in the first crash, may be disabled via a cockpit control. In other 737s, moving the stick was sufficient to disengage it. For some reason, this was changed in the Max, and you must use the other control. However, any competent pilot would know every control in the cockpit. The captain of the latest flight to crash allegedly had 8,00…

Unless I am mistaken, the regular 737s do not have the MCAS installed,just the MAXs ( https://theaircurrent.com/aviation-safety/what-is-the-boeing... ) Additionally it has been suggested that documentation for this physical switch is not well laid out or presented in the manual because Boeing was confident that it would simply stay out of the pilot's way during flight. Assuming pilot error would seem to be premature…

As far as I'm aware, the previous versions gave an audible warning when the flight parameters were exceeding limits. The new system attempts to actively take control and sink the nose. If you know the system from previous aircraft, you'd expect the same behavior in the new one. I'm certain they mention this in training, but if English is not your first language, you'd have to pay particular attention to this part or you're screwed.

Re: US refuses to ground Boeing 737 Max

#274

Post by rtkwe »

darkcha0s wrote: post #273
julianlam wrote: post #263

Earlier quoted context omitted.

Unless I am mistaken, the regular 737s do not have the MCAS installed,just the MAXs ( https://theaircurrent.com/aviation-safety/what-is-the-boeing... ) Additionally it has been suggested that documentation for this physical switch is not well laid out or presented in the manual because Boeing was confident that it would simply stay out of the pilot's way during flight. Assuming pilot error would seem to be premature…

As far as I'm aware, the previous versions gave an audible warning when the flight parameters were exceeding limits. The new system attempts to actively take control and sink the nose. If you know the system from previous aircraft, you'd expect the same behavior in the new one. I'm certain they mention this in training, but if English is not your first language, you'd have to pay particular attention to this part or…

There was no new training for this is what I've read. Boeing thought the new system was simple and similar enough that no retraining was required for the new model.

Re: US refuses to ground Boeing 737 Max

#275

Post by fixermark »

I'm hoping that we aren't seeing a situation where acting FAA administrator Elwell's past service as an Aerospace Industries Association VP and company advocate is biasing his reasoning towards the interest of industry players over public safety.

Re: US refuses to ground Boeing 737 Max

#276

Post by CydeWeys »

ww520 wrote: post #109
stirlo wrote: post #5

Earlier quoted context omitted.

They know Boeing makes up 10.5% of the Dow... [1] or it did before these crashes, currently under 10% due the the stock price dropping [1] http://indexarb.com/indexComponentWtsDJ.html

Dow is a horrible index. It's price-weighted, i.e. higher priced stock has a greater influence than lower priced stock on the index. Apple at $180/share has 2+ times less influence than Boeing at $375/share on the index, and yet Apple's market cap is $850B, 4 times of Boeing's $212B market cap. The Dow index is pure BS.

It boggles my mind that news reports feature the Dow so prominently given how much worse it is than the S&P 500. The Dow is pretty much unsuitable for any purpose save for historical comparisons dating back prior to the advent of the S&P 500.

Re: US refuses to ground Boeing 737 Max

#277

Post by CydeWeys »

sfilargi wrote: post #41
kerng wrote: post #28

What I dont understand is why the airlines themselves (Southwest and American) are refusing to halt the planes - this seems totally irresponsible with what is known at this point.

It’s pretty safe to assume that at this point every fricking pilot out there knows about MCAS and how to deal with it if this specific problematic behavior occurs.

It's been happening during initial ascent, which is a very busy time of flight with little margin for error. Even if you are aware of MCAS, it takes time to recover, and you might not have that much time to spare.

Re: US refuses to ground Boeing 737 Max

#278

Post by gregmac »

Recurecur wrote: post #259
cesarb wrote: post #190

Earlier quoted context omitted.

> Pretty sure the data is that two planes crashed in five months in perfect weather conditions Not only that, but the data we have so far from the second crash (ADS-B data showing irregular vertical speed, see https://www.flightradar24.com/blog/flightradar24-data-regard... ) is consistent with both accidents having a similar cause. Grounding all airplanes from the same model until preliminary data from the (already r…

If it was a "similar cause", it is absolutely pilot error. The MCAS system, at fault in the first crash, may be disabled via a cockpit control. In other 737s, moving the stick was sufficient to disengage it. For some reason, this was changed in the Max, and you must use the other control. However, any competent pilot would know every control in the cockpit. The captain of the latest flight to crash allegedly had 8,00…

There's a good hint at what's going on in a thread from yesterday about the 737MAX reports [1]:

> 1555013 is pretty damning in telling how the airlines treated the MAX as the same type as the 737-800:

> "I had my first flight on the Max [to] ZZZ1. We found out we were scheduled to fly the aircraft on the way to the airport in the limo. We had a little time [to] review the essentials in the car. Otherwise we would have walked onto the plane cold.My post flight evaluation is that we lacked the knowledge to operate the aircraft in all weather and aircraft states safely."

To provide a parallel to the software world, it kind of sounds like they released a "version 2.0" but called it "version 1.1", giving the sense this was a minor revision and anyone that already knows 1.0 will be fine.

[1] https://news.ycombinator.com/item?id=19374386

Re: US refuses to ground Boeing 737 Max

#279

Post by magduf »

lb1lf wrote: post #142
Grue3 wrote: post #140

How improbable was two Malaysian Airlines Boeing 777-200ER flights crashing within five months? Should all Boeing 777-200ER airplanes be grounded? Or all Malaysian Airlines flights? https://en.wikipedia.org/wiki/Malaysia_Airlines_Flight_370 https://en.wikipedia.org/wiki/Malaysia_Airlines_Flight_17 By the way it took years to figure out how exactly these crashed.

-Quite different scenario. One was shot down by a Russian-made surface-to-air missile (And one can hardly fault Boeing for not providing ECM equipment as standard!), the other was (probably) wilfully flown into the great void. Here, on the other hand, there are two eerily similar cases where the likely -mind, likely- common denominator is a new 'feature' which has been undercommunicated to the pilots flying the thing…

>And one can hardly fault Boeing for not providing ECM equipment as standard!

Maybe it should be, for planes flying near or over Russia...

Re: US refuses to ground Boeing 737 Max

#280

Post by unethical_ban »

Recurecur wrote: post #259
cesarb wrote: post #190

Earlier quoted context omitted.

> Pretty sure the data is that two planes crashed in five months in perfect weather conditions Not only that, but the data we have so far from the second crash (ADS-B data showing irregular vertical speed, see https://www.flightradar24.com/blog/flightradar24-data-regard... ) is consistent with both accidents having a similar cause. Grounding all airplanes from the same model until preliminary data from the (already r…

If it was a "similar cause", it is absolutely pilot error. The MCAS system, at fault in the first crash, may be disabled via a cockpit control. In other 737s, moving the stick was sufficient to disengage it. For some reason, this was changed in the Max, and you must use the other control. However, any competent pilot would know every control in the cockpit. The captain of the latest flight to crash allegedly had 8,00…

>However, any competent pilot would know every control in the cockpit.

Not if they tell you the plane acts the same, and then it doesn't! Did Boeing inform pilots of this change proactively? Was the pilot trained on the change, and perhaps even recertified?

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