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Boeing's Crashes Expose Systemic Failings
- PhasmaFelis 7y ago> By the end, the planes had gained so much speed and were descending so steeply that the pilots would have had to possess superhuman strength to counter the pressure on the horizontal stabilizer trim. I thought these systems were all fly-by-wire now? Edit: Don't downvote for asking an honest question, guys. Thanks to the people who actually answered.
- yeezul 7y agoMy understanding is that the 737 does not use Fly by wire [1] and if I remember correctly it's because they wanted to piggyback on the original 737 certification. I could be wrong. 1: https://www.quora.com/Does-the-737-MAX-family-use-fly-by-wire https://www.quora.com/Does-the-737-MAX-family-use-fly-by-wir...
- lisper 7y ago> I could be wrong. You're not :-) The 737 still has direct mechanical linkages to the control surfaces. Changing that would require completely redesigning the aircraft.
- xvector 7y agoWhat's the motivation for this? Regulatory, I get that. But why use direct mechanical linkage in an era where fly-by-wire would probably be faster/safer/etc?
- afterburner 7y agoCost. Not just cost of manufacture/design, but billing it as cheap because you won't have to retrain all your old 737 pilots. Not training the pilots properly was a feature (cheaper for the airlines), and Boeing deliberately wanted to avoid saying they would actually need the training because that was their whole selling point and the reason for all these weird decisions.
- markbnj 7y agoI'm not a pilot, but from what I have read many pilots actually prefer mechanical linkage to the control surfaces. Sullenberger even indirectly blamed fly-by-wire systems (in this case the lack of a link between pilot and copilot controls) for the crash of Air France 447: https://www.cbsnews.com/news/air-france-flight-447s-lessons-four-years-later/ https://www.cbsnews.com/news/air-france-flight-447s-lessons-...
- PaulHoule 7y agoOne of the most popular features of Boeing aircraft is that there is a mechanical linkage between the yokes of the pilot and copilot. Boeing's modern planes (not the legacy 737) have fly by wire where there is still a mechanical connection between the yokes. Thus you have the nice shared feel, but you have the benefits of fly-by-wire. There have been accidents where fly-by-wire has been part of the problem but there have also been failures of the old mechanical linkage systems. Airliners have had active systems to cancel out unstable modes for a long time (e.g. to suppress "Dutch Roll" on the old 727) The A320 has particularly been plagued by extreme "human error" situations where people crashed the plane after seemingly trying to crash it. For instance the first passenger flight involved a stunt that resulted in a crash. later on New Zealand regulators who were investigating fly-by-wire glitches tried to provoke the fly-by-wire system into failing when they were approaching a runway and they wound up dead.
- hylaride 7y agoBecause the plane would have certainly then required expensive/time consuming re-certification and expensive/time consuming (for the airlines) retraining of pilots, which Boeing was trying to avoid with the max. Keep in mind, the 737 originally flew in the late 60s. It's obviously now a very different aircraft, but if they were going to go fly-by-wire and require re-certification, they'd have designed a whole new aircraft (something a lot of people would have preferred even before the crashes). The 373 max was a comparative rush job. When Airbus released the A320neo (the A320 first flew in the late 1980s so already was fly-by-wire), Boeing needed to get a comparable plane out ASAP or else cede several thousands of plane sales to Airbus. There wasn't the time to design a whole new plane, so they pushed the design of the 1960s era 373 as far as they could go. The details of the "risky" changes to accommodate the larger engines (that significantly changed the planes aerodynamic profile) and attempts to compensate for that are already documented elsewhere, but adding fly-by-wire would have only made things more complicated.
- BurningFrog 7y agoYeah, the regulatory incentives seem to be a substantial factor here.
- msbarnett 7y agoNot really. Market forces drove Boeing to rush out a more fuel efficient 737. Even absent regulatory incentives, market forces drive them to want to deliver a 737-dimensioned plane, because a huge selling point for the NG and MAX is that they're still compatible with decades' old infrastructure at rarely-upgraded regional airports. Bolting large enough engines to deliver the market-desired fuel efficiency on the market-desired airframe dimensions of the MAX necessarily required mounting them so far forward that the entire airframe is fundamentally prone to pulling into a stall, and correcting that is why MCAS exists. Certification costs are far from the only reason Boeing has never sat down and designed a successor for 737, even though they've done so for numerous other planes -- half the problem with the 737 is that its engineering achilles heel (the incredibly low ground clearance) is simultaneously a key feature to a large portion of the customer base. Correcting it means all of those customers finally upgrading their ground infrastructure, which leads to Airbus suddenly being a viable competitor for those routes.
- jfnixon 7y agoSo if the A320neo isn't suitable for a large portion of the customer base, how is it a competitor to the 737MAX 8?
- msbarnett 7y agoIt was significantly more fuel efficient on the sorts of routes the non-MAX 737 dominated, to the point where airlines and airports were starting to redo their infrastructure to accommodate it because the fuel savings were cheaper in the long run. Rushing out the MAX let them shore up their advantage in that market — get the fuel savings AND save on the upgrades you won’t need.
- msbarnett 7y agoThe 737 series, including the MAX, has mechanical linkages to the control surfaces. Boeing’s recommendation for dealing with a runaway MCAS scenario, in fact, was to cut power to the stabilizer trim motors at just the right moment in a short window of opportunity between cycles of it running, and then have the pilot manually crank the trim by hand turning a wheel that pulls a cable. With excessive speed, or too much counter-force being put on the stabilizer by pulling back on the stick (because the pilots didn’t cut the electricity fast enough inside the cycle window, leading to the stabilizers forcing the nose down and the pilots needing to counter that to keep above the ground), the wheel can require an enormous, potentially insurmountable amount of force to operate.
- FabHK 7y agoYes. Truly terrible. And, possibly the pilots could turn the wheel if both collaborated on it - but then, who pulls back the control column to keep the elevator up? Terrible terrible situation.
- bronson 7y agoAnd how long can you hold it at max effort? Should MAX-8 training include a physical fitness component?
- ricardobeat 7y agoThere was a video circling around of pilots flying the MAX in a simulator, and reproducing the failure conditions; they were unable to physically hold the trim wheel to counteract the system.
- magduf 7y agoIt absolutely should, so that only strong men can possibly pass. Then, since this is absolutely sexist and prevents female (or less-strong men) from flying the plane, either the plane should be non-certified, or Boeing should have to pay full lifetime salaries for any not-strong-enough pilots who want to file a claim that they can't fly this plane.
- barkingcat 7y agoThe plane in question is the 737 Max, which is the renewed version of the 737 series that started production in 1968. The whole family of planes does not have fly-by-wire.
- deleted 7y ago[deleted]
- the_duke 7y agoThe article explains this further...
- british_india 7y agoThese software failures expose the folly of outsourcing all software development to Indian contractors.
- nness 7y ago> Bickeböller's complaint endangered the planned inauguration of the 787, which had already been delayed due to technical difficulties. The problems identified by the engineer, however, weren't addressed by Boeing, which is why he turned to EASA in June. [...] In those papers, it states that management and top executives at Boeing had ordered that the coordination problems with the company's suppliers be "closed." The reason: "to get the 787 production certificate." I, for one, hope this plane never flies again.
- dsfyu404ed 7y agoWe're talking about the 787 here, not the 737 variant that's falling out of the sky. Despite initial teething issues (something all big systems like this have to some extent) the 787 has gone on to be a successful design. To say "I, for one, hope this plane never flies again" is an overreaction, especially since said problems have been fixed and the plane is in service without the issue popping up.
- CivBase 7y agoIf those are teething issues, I'm scared to find out what you'd consider to be a serious problem.
- CydeWeys 7y agoThey're fixed now, is the point. It wouldn't make sense to pull 787s now because the problems are fixed and it would throw global air travel into chaos and disarray (since this plane is now so widely used).
- denton-scratch 7y agoWot? Potentially-dangerous planes must be kept flying, because air-travel chaos and widely-used-ness?
- AnimalMuppet 7y ago
- linuxftw 7y agoIt's obvious to me neither the FAA nor Boeing attempted to accurately replicate the first crash scenario, because this could have wholly averted the second crash. As soon as the planes were grounded, we were getting all sorts of reports about the stablizer being too hard to move and basically an unrecover situation. Jail time is the only outcome I will accept.
- FabHK 7y agoHow is it obvious to you that they didn't investigate the first crash sufficiently? I'd say some time after the first accident it was reasonably well understood what had happened, and the FAA (and many others!) concluded that it was still safe to fly the plane, as the pilots could easily interrupt the accident chain by doing the right thing quick (as the pilots on the Lion Air flight preceding the accident flight had done). Why that assessment was wrong is a complicated story that has to be examined carefully. From what I gather, in aviation safety circles "jail time" is very rarely considered a wise answer. As soon as you threaten jail, people will cover their ass and obstruct investigations. Instead, the goal is and should be to examine the entire system to ensure accidents don't repeat, and by and large, the system works exceedingly well.
- LifeLiverTransp 7y agoSo, asses are currently uncovered?
- afterburner 7y agoJailtime for those in management who are responsible for cover-ups and cut corners. Not jailtime for those who actually design and handle the equipment.
- jellicle 7y agoI've never quite understood that argument that only little people benefit from jail time and important people do not. Surely if we can put someone in jail for a year for having a forbidden plant in their pocket then we could put someone in jail for - how about a week? Three days? An hour? - for choosing to cut corners on safety and smashing two planes full of people into jelly? The root cause here is "Boeing management wanted to get a plane out quick so they didn't lose market share". The way to examine the system and make sure this doesn't repeat (for now...) is to put someone in jail for it. Then the next time that some plane company wants to cut corners and get an unsafe plane out quick, some manager who doesn't want to go to jail will put a stop to it. Show me the flaw in my logic.
- FabHK 7y ago> What's more, over the course of his 55 years in the profession, he [lawyer Marc Moller] [has] learned that every plane crash can be traced back to a single, simple cause. I don't know, that strikes me as nonsense. It's precisely the interplay of many factors that lead to an accident - and if any one of them had been different, the outcome might have been different. See Reason's "swiss cheese" model of accidents - all the holes have to line up [1]. How you can go and designate one of these holes the hole, the "single, simple cause" is beyond me. This doesn't do the complexity of engineering justice. Might help to win cases with juries, but I don't see how it could help to make flying safer. [1] https://en.wikipedia.org/wiki/Swiss_cheese_model https://en.wikipedia.org/wiki/Swiss_cheese_model
- notfashion 7y agoThe journalist writing the article may have distorted what he said. Is their a dogma of accident investigation that says there is always a root cause, or is it just a conventional way of working? There are certainly domains in which root cause analysis is inappropriate—psychiatry, for example. https://en.wikipedia.org/wiki/Root_cause_analysis https://en.wikipedia.org/wiki/Root_cause_analysis
- nness 7y agoI think, as a lawyer, he's using the phase a "simple cause" to mean "a singular responsibility, culpability, and liability."
- FabHK 7y agoProbably. Goes to show that the lawyer representing the victims and the safety folks (NTSB etc.) trying to make sure an accident does not repeat have very different goals, incentives, ways of thinking, etc.
- mieseratte 7y agoGiven how vague the language is, I don't know that we can necessarily draw a conclusion. That "single item" might be the component-failure, that which fell through the aligned holes in the swiss-cheese, or it could be "the single layer of the system that was left out" that would have mitigated or otherwise precluding the class of failure. One could castigate Boeing for not having a more redundant use of sensors the MAX case, or one could say "Why don't you have 'hackers' as a part of your process, whose job it is to find these classes of problems and raise all hell when they do." Then again based on the phrasing "single, simple cause" I'm more inclined to say you're on the money. That the lawyer is looking at the component-failure rather than "avoiding non-redundant systems" as a class of problem to solve.
- papito 7y agoThis is probably the best piece I've read about this: "How the Boeing 737 Max Disaster Looks to a Software Developer" https://spectrum.ieee.org/aerospace/aviation/how-the-boeing-737-max-disaster-looks-to-a-software-developer https://spectrum.ieee.org/aerospace/aviation/how-the-boeing-...
- SilasX 7y agoHN discussion: https://news.ycombinator.com/item?id=19694207 https://news.ycombinator.com/item?id=19694207
- hhas01 7y agoHow the Boeing 737 Max Disaster Looks to a Software Developer “Ehhh, we’ll patch it in the next release…”? /badum-tish (Actually a really deep and insightful read. Tx.)
- salawat 7y agoObligatory further reading repost. https://www.seattletimes.com/seattle-news/times-watchdog/the-inside-story-of-mcas-how-boeings-737-max-system-gained-power-and-lost-safeguards/ https://www.seattletimes.com/seattle-news/times-watchdog/the... EDIT: What? It's one of the better written articles that actually includes most of the technical details, plus some of the corporate environment related ones. The two articles together are basically guaranteed to contain all the essentials one needs to understand what happened.
- noneeeed 7y agoThe Seattle times has had some of the best reporting on this, presumably because they have been covering aviation for a long time. I've found some of the tech press have (not surprisingly) treated it too much as a technical issue in the sense of it being about broken software or hardware. This whole disaster has been a great example of the importance of good systems and safety engineering, of effective oversight, and of a good safety culture. What is depressing about it is that the aviation industry worked hard for decades to develop an open and effective safety culture, and Boeing seem to have forgotten a lot of the painful lessons of the past. Hopefully, if anything good comes out of this situation, it will be a reinforcement of the culture and mindset that has made commercial flight incredibly safe.
- thepaperone 7y agoDaily reminder that Boeing outsourced their work to minimum wage international labor.
- darknoon 7y agoI saw this documentary about issues with the 787 back in 2014, and it was clear that something was massively wrong at Boeing: https://www.youtube.com/watch?v=rvkEpstd9os https://www.youtube.com/watch?v=rvkEpstd9os The engineers doing the work know what it takes to make a good airplane. Let them do their jobs.
- effnorwood 7y agoThey don’t. Where is Airbus made again?
- Havoc 7y agoAt this rate they're getting a US bailout. I don't recall Boeing positive anything recently. And as much as it fuckin irks me...US better throw them a juicy bailout if necessary. Because one aircraft manufacturer global monopoly would be a epic shitshow. Boeing and Airbus have to walk away from this alive and roughly equal.
- Xixi 7y agoDon't worry, the duopoly will soon die. Comac is coming with the C919 and C929, and with a huge captive domestic market they are bound to succeed (given enough time). I know I will sound cynical, but if the past is any indication of what's coming, it is entirely possible that a decade from now Airbus and Boeing won't be able to fight for Chinese orders anymore, while Comac will enjoy the ability to fight for every single American and European order...
- magduf 7y agoNo, they don't. Boeing should not be able to continue as a company, especially with its current management. There is absolutely a huge need worldwide for large passenger aircraft, however, but the answer is very simple: sell Boeing's assets at fire-sale prices to another (probably foreign) company and let them take over. Perhaps Bombardier would like to massively expand? Or what about Mitsubishi? Or Embraer? Any of those companies could take over Boeing's factories and operations in relatively short order and start building new and safer planes.
- ackfoo 7y agoWhat an absolute hatchet job. Ask lawyers who have a vested interest in finding someone with deep pockets at fault so they can collect on contingency. None of you apparently wishes to hear it, but the cause of both these crashes, most proximately, was poor training of the flight crews. Whatever Boeing did or did not do, and whatever corners they may have cut to reduce cost and remain competitive, these crashes cannot be laid at their door. It's the inconvenient truth. The unpopular opinion. From the one person here who seems to have read and understood the preliminary accident reports and the FDR data: these aircraft experienced a runaway trim situation, and, whatever the cause, that is something that pilots must be trained to recognize and respond to without consulting the checklists. Boeing and basic flight training provided everything needed to handle these emergencies. We can argue (as ALPA no doubt will) about the adequacy of training materials and what Boeing should have made sure pilots knew about the systems, blah, blah, blah. In the end, if you cannot recognize a runaway trim condition in any aircraft you need to get busted back to flight school to start again.
- blt 7y ago> Boeing developed a software program that constantly monitored the angle of attack. As soon as this angle became too risky, the Maneuvering Characteristics Augmentation System (MCAS) would automatically lower the plane's nose without the pilot having to do anything at all. To do so, it doesn't manipulate the rudder, but the horizontal stabilizer trim, the most forceful control surface on the entire aircraft. How could the rudder possibly be used to change the angle of attack? Isn't the horizontal stabilizer the only control surface that can do this?