Boeing 7*7: the saga continues…

[MaverickSawyer]

8 hours ago, wizzlebippi said:

The regs are written in blood. Never forget that.

^THIS.

SO. MANY. LESSONS. have been paid for in blood. Just this week in my Airframe Systems class, we were talking about fuel tank inerting and how the TWA 800 accident led to the requirements for it. (AC 120-98A, if you're interested in reading the actual regs involved.) The week before that, we looked at the crash of ValuJet 592 as we studied chemical oxygen generators. Air travel is as safe as it is because of the lessons paid for in blood. And sometimes, those lessons pay off by saving lives. Look at Aloha Airlines Flight 243, or United Airlines Flight 811. Both of those aircraft were able to land due to lessons learned from the DeHavilland Comet crashes.

I won't stop anyone from being armchair accident investigators. I will, however, remind you that if your only source is mainstream media, they will ounce on any and every last little detail that makes a mountain out of a molehill, because they want to scare the everloving c**p out of you to keep you watching them. (That's actually good advice for everything they do, but that's not the point of this thread...) They have ZERO interest in telling the full, unbiased story.

18 hours ago, mikegarrison said:

The more someone *actually* knows about something like this, the fewer specifics they will post in an open forum. Wait for the NTSB reports.

Yep. Actual experts will sit tight and not say anything to the media that can be misconstrued, for reasons I detailed above. The "experts" you see on talk shows and news reports, however, are being paid to provide their opinions to the media outlets. I certainly acknowledge their experience and wisdom, but I don't trust their assessments much unless backed by hard evidence.

[mrfox]

“On no other 737 is there a system based on the angle of attack that will move the (horizontal tail) trim. That is unique to the MAX,” said Cox, the CEO of the aviation consultancy. “I was surprised that a single angle of attack indicator could cause the activation of this system.”

https://www.seattletimes.com/business/boeing-aerospace/faa-follows-boeings-737-safety-alert-with-an-emergency-directive/

note the description of the "auto-trim" feature for the 737 is completely wrong in this article. The STS is the exact opposite of auto-trim - more like an anti auto trim.

[YNM]

5 hours ago, MaverickSawyer said:

I will, however, remind you that if your only source is mainstream media, they will ounce on any and every last little detail that makes a mountain out of a molehill, because they want to scare the everloving c**p out of you to keep you watching them

Our media here were having people straight from indonesian NTSC (KNKT). It was brilliant, actually - practically a public physics lecture live on national TV outlet. (he only discussed the basic operations of aircraft, didn't say a word about how it might have crashed.)

Though I'll have to say that you can't lie to your customers either (which in this case is the layman people, the average joes who use aiplane for their transportation needs). If you lie to them you're just putting yourself in a heap of garbage as well.

Edited November 11, 2018 by YNM

[MaverickSawyer]

8 hours ago, YNM said:

Our media here were having people straight from indonesian NTSC (KNKT). It was brilliant, actually - practically a public physics lecture live on national TV outlet. (he only discussed the basic operations of aircraft, didn't say a word about how it might have crashed.)

Though I'll have to say that you can't lie to your customers either (which in this case is the layman people, the average joes who use aiplane for their transportation needs). If you lie to them you're just putting yourself in a heap of garbage as well.

I can't speak for media outside the US, so maybe your country actually has journalistic integrity? God knows we've lost ours years ago in pursuit of profits.

And they don't lie... They simply don't tell the full truth if a partial truth can be spun into a fearmongering headline.

[YNM]

7 hours ago, MaverickSawyer said:

And they don't lie... They simply don't tell the full truth if a partial truth can be spun into a fearmongering headline.

Rest assured I'd have detected them at point blank if I saw it.

If anything, the person from KNKT was kind of live commentating on the salvage operation. I saw a glimpse of the whole affair when they lifted up one of the engine cores. It was like the engine core had been released off the cowling.

[Nuke]

sensors are cheap, 737s are expensive. better to stack those sensors than crash those planes.

[YNM]

51 minutes ago, Nuke said:

better to stack those sensors than crash those planes.

The technicians "replaced" the sensors on the previous flight. Of course the details are still being worked out.

[MaverickSawyer]

8 hours ago, YNM said:

Rest assured I'd have detected them at point blank if I saw it.

If anything, the person from KNKT was kind of live commentating on the salvage operation. I saw a glimpse of the whole affair when they lifted up one of the engine cores. It was like the engine core had been released off the cowling.

Again, I can only speak to American media outlets. YMMV.

That's... kinda to be expected. The engine core is one of the strongest parts of the aircraft, with only the wing box and the landing gear struts being comparable.

[magnemoe]

On 11/11/2018 at 5:31 PM, MaverickSawyer said:

I can't speak for media outside the US, so maybe your country actually has journalistic integrity? God knows we've lost ours years ago in pursuit of profits.

And they don't lie... They simply don't tell the full truth if a partial truth can be spun into a fearmongering headline.

Have an feeling media is mostly after clicks this day.
And yes this is an 150 year old problem, however then it was newspapers sold. 
 

[wizzlebippi]

https://www.avweb.com/avwebflash/news/Pilots-Not-Told-About-737-MAX-Auto-Trim-System-Updated-231846-1.html

An update from a site that understands aviation. Apparently pilots were not made aware of the system that brought down Lion Air 610 in their type rating/differences courses.

[StrandedonEarth]

I saw a blurb about that on the news last night. Major US airlines like SW Air  are complaining that their pilots were never told about the difference or how to counteract the system when it went haywire 

[Gargamel]

2 hours ago, StrandedonEarth said:

I saw a blurb about that on the news last night. Major US airlines like SW Air  are complaining that their pilots were never told about the difference or how to counteract the system when it went haywire 

They should have just hit Ctrl-X... reset that trim. 

[Nightside]

I'm reviving this thread after reading 2 fascinating articles this week about how Boeing's shift over the last couple decades from a company that valued it's engineers and had a world renowned culture of innovation and safety became one that appears to be driven by greed alone. Although the victims of the 737 Max planes operated by Lion Air and Ethiopian paid the price, Boeing's focus on money over good product also has ramifications for their spaceflight projects as well.

https://www.theatlantic.com/ideas/archive/2019/11/how-boeing-lost-its-bearings/602188/

https://www.newyorker.com/magazine/2019/11/18/the-case-against-boeing

And, not specifically related to Boeing or the 737 Max, but an interesting take on how adding complicated safety features to complex systems can have disastrous consequences.  

https://99percentinvisible.org/episode/cautionary-tales/

[mikegarrison]

20 hours ago, Nightside said:

And, not specifically related to Boeing or the 737 Max, but an interesting take on how adding complicated safety features to complex systems can have disastrous consequences.

This latter concept is probably more to the point of the case of MCAS. Many things that were intended to be safety features (stick shaker, over-speed warnings, MCAS itself) appear to have overloaded the pilots' ability to process the information in the two crashes.

[wumpus]

On 11/9/2018 at 10:58 AM, p1t1o said:

This makes me think that the "aggressive" or "abrupt" dive (as described by boeing) was SO aggressive that the pilots were prevented from taking this simple remedial action.

And thats quite a violent error. Unless Im missing some key piece of information.

Media reports (so take with an appropriate salty lake) implied that the pusher is simply stronger than humans.  Once the pilot and copilot were too tired from fighting the pusher, you get an abrupt dive when the pusher takes over.

On 11/9/2018 at 12:01 PM, wizzlebippi said:

There should be a red override/disconnect button on both pilot's controls that if held would stop the pusher from firing. The aircraft may have been very nose down once the pusher was overridden, and the crew may have not recovered properly (throttles idle, speedbrakes extended, pull to 1.5-2g).

This is a massive economic/political can of worms.  The key spec to the 737-MAX was that it "flew the same as a 737" and didn't require any additional training.  Including such a "throttle/disconnect" is to put a lie to that spec and leave Boeing on the hook for all training of pilots for this "new" aircraft.  They absolutely will do everything they can to keep that from happening.

On 11/10/2018 at 4:51 PM, mikegarrison said:

The speed stability system has been on 737s since at least the Next Gen. It's not a new system. It has worked as intended for more than 20 years.

Which implies that there might be a problem with the 737MAX not acting similar to a "real" 737 since the engines are in the "wrong place".

One thing that might not be clear is just how rigorous FAA-controlled software development is.  As far as I know (which is out-of-date second-hand information), a coding error (to the spec) is next to impossible.  Any software error almost has to be part of the specification which implies deep issues that will take a very long time to fix (if only due to all the regulation and testing, and when this is done in parallel to plane development it shouldn't create huge delays).

Is it true that an actual coding bug would be a scandal on par with crashing two aircraft?

My take is that it is likely not so difficult to adjust the MCAS to work correctly on the 737MAX (and include all the sensors by default).  I'm guessing that the delay is that all such quickly implemented measures require significant (by a cost standpoint) levels of training for pilots.  There's also the additional issue of just how much stink this has made and what it will take to get pilots (and passengers) to fly a 737MAX once the grounding has been lifted.  But lack of any word of a fix strongly hints that Boeing isn't happy with potential fixes (although it may well be that while Boeing would happily leak such information against the FAA's whims, the FAA isn't in control of the grounding.  China (and Europe) matter a lot more world-wide and few trust the FAA in this matter).

Edited November 24, 2019 by wumpus
forgot MCAS

[mikegarrison]

10 hours ago, wumpus said:

Media reports (so take with an appropriate salty lake) implied that the pusher is simply stronger than humans.  Once the pilot and copilot were too tired from fighting the pusher, you get an abrupt dive when the pusher takes over.

This is not quite right.

The electric motors that drive the jackscrew are stronger than what can usually be input by the pilots, but pilot input overrides the automatic input, so this doesn't matter. There was an issue with the Ethiopian flight where the airplane entered an overspeed situation and the increased load on the stabilizer apparently made manual trim adjustment effectively impossible.

(From what I have read, pilots were long ago taught a "roller coaster" technique where they repeatedly dived to take the load off the stab, adjusted the trim and then pulled out of the dive. This technique is apparently no longer taught.)

By the way, there are cutout switches that stop the electric motors from being able to drive the trim system. They are available on both the NG and the MAX. In the case of the first Lion Air flight, the pilots used those switches and safely landed the airplane. In the case of the second Lion Air flight, they did not use those switches and the airplane crashed. In the case of the Ethiopian flight they used those switches, but then later turned them back on again.

Edited November 25, 2019 by mikegarrison

[tater]

 

[WestAir]

Once upon a time I used to fly for two separate carriers, and before that I was a flight instructor. I haven't flown anything since 2016 but stuff like this makes me relieved to have left the industry.

Everything I've heard about this debacle, including from two of my old coworkers who are both FO's at Delta, terrifies me to no end. What happened was beyond inexcusable. We are not new to the jet age; the terrors of the DeHavilland Comet or the DC-10 should have taught us the patience, strategy, and foresight to prevent single point accidents. 

I'm curious to see how the industry changes in response to the Max.

[Kerbart]

1 hour ago, WestAir said:

We are not new to the jet age; the terrors of the DeHavilland Comet or the DC-10 should have taught us the patience, strategy, and foresight to prevent single point accidents.

We also had a decade and a half with nearly no accidents, which creates complacency. Not necessarily on the design process itself—although hard to believe, Boeing engineers might truly have thought this solution was less prone to failure (less parts after all) or at the very least safe enough.

But where the process obviously failed (without being an armchair analyst, or so I'd like to think)  is the review process where the FAA left matters to Boeing (basically “when we say it's good, it means it's good and no need to review it” and that has complacency written all over it.

From what I read in the press, the FAA is not going to let that happen again (at least not with the 737 MAX) but doesn't have the manpower either, which is why the re-certification is going to take so much time.

On 12/23/2019 at 9:44 AM, tater said:

 

Sports teams do that, too. Fire the coach. Basically “we ran out of ideas and don't know what to do but we need to do something” It'd be nice to see some people going to jail for this, but the loss of a couple of hundred lives is probably not serious enough; that's reserved for the true villains who cheat on emission tests.

[mikegarrison]

17 hours ago, WestAir said:

Once upon a time I used to fly for two separate carriers, and before that I was a flight instructor. I haven't flown anything since 2016 but stuff like this makes me relieved to have left the industry.

Everything I've heard about this debacle, including from two of my old coworkers who are both FO's at Delta, terrifies me to no end. What happened was beyond inexcusable. We are not new to the jet age; the terrors of the DeHavilland Comet or the DC-10 should have taught us the patience, strategy, and foresight to prevent single point accidents. 

I'm curious to see how the industry changes in response to the Max.

It was very definitely *not* a "single-point" accident. Unless you mean the single point being the flight crew, but as long as we have flight crews I don't see a way around that. No dogs in the cockpit.

If you do believe it was a single-point accident, perhaps you can explain how the Lion Air airplane managed to successfully fly to its destination and land the flight immediately prior to the fatal flight?

Both the crashes involved whole sequences of things going wrong, both with the airplane and with the flight crew response.

Edited December 31, 2019 by mikegarrison

[WestAir]

4 hours ago, mikegarrison said:

It was very definitely *not* a "single-point" accident. Unless you mean the single point being the flight crew, but as long as we have flight crews I don't see a way around that. No dogs in the cockpit.

If you do believe it was a single-point accident, perhaps you can explain how the Lion Air airplane managed to successfully fly to its destination and land the flight immediately prior to the fatal flight?

Both the crashes involved whole sequences of things going wrong, both with the airplane and with the flight crew response.

That's a fair rebuttal. I stand corrected.

[StrandedonEarth]

5 hours ago, mikegarrison said:

It was very definitely *not* a "single-point" accident. Unless you mean the single point being the flight crew, but as long as we have flight crews I don't see a way around that. No dogs in the cockpit.

If you do believe it was a single-point accident, perhaps you can explain how the Lion Air airplane managed to successfully fly to its destination and land the flight immediately prior to the fatal flight?

Both the crashes involved whole sequences of things going wrong, both with the airplane and with the flight crew response.

Well, it could be argued that it is single-point in that one faulty sensor would crash the plane if the proper corrective action is not taken by the crew. But these accidents ultimately fall under the swiss-cheese accident model. The thing is, gaping holes were left in at least three slices of cheese; from hardware to software to pilot training. Engineering too, if they are stretching the basic 737 design so much that they have to resort to these tricks to keep the beast stable.

[mikegarrison]

59 minutes ago, StrandedonEarth said:

Well, it could be argued that it is single-point in that one faulty sensor would crash the plane if the proper corrective action is not taken by the crew. But these accidents ultimately fall under the swiss-cheese accident model. The thing is, gaping holes were left in at least three slices of cheese; from hardware to software to pilot training. Engineering too, if they are stretching the basic 737 design so much that they have to resort to these tricks to keep the beast stable.

I think the best discussion of the whole situation was the one published in the New York Times back in September. https://www.nytimes.com/2019/09/18/magazine/boeing-737-max-crashes.html

[tater]

https://www.theverge.com/2020/1/9/21059420/boeing-employees-messages-737-max-investigation-simulator-crash

This article actually links to all the emails... I haven't read all of them (yet), but wow.

 

[mikegarrison]

https://www.bloomberg.com/news/articles/2020-01-16/expert-panel-recommends-reforms-after-review-of-737-max-approval

Some interesting conclusions:

The certification process under which manufacturer employees are deputized to approve designs should continue, although there needs to be better protection against pressure from company management.

Overall the FAA's certification system is effective, but the FAA is understaffed.

The assumptions about how pilots will react need to be better assessed. (The assumption that was important to 737 MAX was that pilots would turn off the trim motors within three seconds after the airplane started putting in trim without being commanded to do so. This was why a mistaken MCAS activation was assumed to be only "hazardous". In the fatal Lion Air flight, the pilots never turned off the trim motors. In the Ethiopian flight, they turned the motors off but eventually turned them back on again.)

The standard for pilot training needs to be improved.

=======

Some articles reporting on this are putting a more negative spin on it, pointing out that the panel is basically the FAA and industry assessing their own performance. https://www.politico.com/news/2020/01/16/737-max-boeing-faa-099700