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The world pulls the Andon cord on the 737 Max
- PaulHoule 8y agoIt is nice to see articles out highlighting that Boeing's choice to string the 737 along will come at great cost.
- marcc 8y agoWhy is this? I’m not an expert or really follow the airline industry too closely. I’m curious to understand what about Boeing’s decision to continue the 737 line prompts your comment.
- deleted 8y ago[deleted]
- llukas 8y agoThey slapped new engines on old airframe to save costs of qualifying new airframe and airlines save costs on retraining crews.
- PaulHoule 8y agoIt's a very big picture. The reason you feel like hell after taking the Redeye isn't that just that you took the Redeye, but you took the Redeye on a 737. The marketing term "narrow-body" belies that the 737 is wide enough but not tall enough for the human physique. Just thinking about the curve of that circular fuselage makes my neck start to knot up. Don't believe me? The Embraer 195 is a smaller plane that feels huge on the inside compared to the 737. More advanced planes like the 787 use electric bleed air to save energy and vent less toxic fumes from the cabin which also makes air travel more pleasant. The fuselage cross-section dates back to the 1958 Boeing 707. There is great concern about the environmental impacts of air travel and since 737-class planes (like the Airbus A320) are produced in greater numbers than other aircraft, the flying public, the world, and the airlines deserve something better as an everyday flyer.
- saagarjha 8y agoIt's hidden at the end, so I thought I'd put it up here: an Andon cord is a way to notify management of issues in the assembly line, typically by pulling it: https://en.wikipedia.org/wiki/Andon_(manufacturing) https://en.wikipedia.org/wiki/Andon_(manufacturing)
- vonseel 8y agoSeems like such an odd name for a cord that “stops” production... I imagined by the naming that the world must have resumed flight of the 737 Max or something like that. “And.... on!” or a race “and... go!”. Good to know, I wasn’t aware of these in factories.
- dmoy 8y agoIt's derived from a language other than English. Japanese? Something...
- robin_reala 8y agoJapanese: 行灯. It’s the classic Japanese lamp, I guess pressed into use as a warning signal in factories? https://en.wikipedia.org/wiki/Traditional_lighting_equipment_of_Japan%23Andon#Andon https://en.wikipedia.org/wiki/Traditional_lighting_equipment...
- Theodores 8y agoI think it is the wrong word, it is a fundamental design problem and back to the drawing board, not a matter of fixing some quality control issues. I think the word they were looking for was 'Samsung Note 7' not 'Andon cord'.
- asplake 8y agoIt’s common term in Lean circles. For people who (like me) prefer not to use Japanese terms when an English one will do, “stop the line”.
- fouc 8y agoWhy was a new single-aisle plane important?
- kalleboo 8y agoThe continued pursuit of increased fuel efficiency. Airbus managed to make their A320neo more fuel efficient than Boeing's 737 and so Boeing were at risk of losing customers to Airbus. The new, more efficient engines are bigger and hence didn't fit under the wings of the 737. Hence the "hacks" Boeing did to fit them on 737 that required software augmentation to get it to work safely. A newly designed plane taking into account the size of the engines would have been more inherently stable without software augmentation. Boeing's solution will probably be to improve the software augmentation by fixing the behavior of error detection and correction in the case of sensor troubles (such as adding clear warnings which some airlines have already added as a optional features)
- salex89 8y agoMaybe it's an overstatement, but further improvements on the 737 is beating a dead horse. Maybe even the MAX was a stretch, but if it weren't for this particular issue, it would live a long and happy life. Not that it won't after this fixes. It will probably be the most audited plane in the skies. It's a great plane that connected the world, surely, but there is no denying that the A320 family is just more modern and still has more potential to be squeezed from it. Starting from the trivial facts that it has a higher ground clearance and the cockpit has more room to improve on instrumentation.
- toast0 8y agoA lot of commercial flights are on single-aisle planes. The 737 is a very old design, with many updates, and a brand new plane designed from the ground up to fit today's market will likely be more significantly more efficient. It's just that the 737 has been good enough with changes every so often for a long time, so Boeing has done a lot more fully new designs for larger planes; some of which had tremendous gains in efficiency while increasing passenger comfort; the 787 is reported to use about 20% less fuel than the 767.
- speeq 8y agoI wonder what their management team was thinking.. "We're going to make so much money by not having to retrain pilots for this new plane!" Reality: Hundreds of people die within months. Boeing is now worth $25 billion less in market cap and the planes are grounded worldwide.
- mikejb 8y agoDecisions like this probably worked out for them a lot in the past, so this one just seemed like another genius money-saving move. Until shit started to hit the fan, that is.
- kodz4 8y agoReality is also that the rest of the world tested and bought the planes. In the hundreds. There is too much media BS about this stuff. If Boeing says its going to take 10 years to fix, what is anyone capable of doing about it? I can say for example, that tomorrow Airbus is going to get broken up and turned into a mess because of Brexit, and everyone from the President of France to the Airbus leadership can be blamed for it. Reality is anyone can blame whatever they feel like these days. Anything surrounding blame can be safely ignored. Look for the people talking about the solutions.
- andromedavision 8y ago.
- donkeydoug 8y agoSo... they put in software (MCAS) to try and auto-assist in certain situations so that flying the 737 Max would respond like flying the current 737. But seems like an indicator light to show when the sensors that activate that system trigger isn't standard equipment & the sensors may very well have a bad baseline read before takeoff and the system kicks into gear and auto-crashes the plane if you don't know how to disable it. Yeah, I'm never flying in one of those things :-)
- WalterBright 8y agoPilots are trained in how to disable it - the stab trim cutoff switches are right there on the console. The mystery is why the pilots didn't follow their training.
- mikejb 8y agoI've seen different reports about what's in the training. I think the challenge here is to detect that the system is running haywire and then disabling it. It's not a common situation, never trained, and possibly only something the pilot might have read on the way to the airport. Not ideal for a high-stress situation.
- WalterBright 8y agoOn the 737 airplanes, when the stab trim is running a wheel on the side of the center console turns and makes a loud clacking sound. It is designed to be obvious. You can see a picture of the wheel here: https://www.quora.com/What-are-the-spinning-wheels-in-an-airliners-cockpit https://www.quora.com/What-are-the-spinning-wheels-in-an-air...
- mikejb 8y agoYou have to make the connection though: that clacking noise is probably that new system I read about doing something. Then you have to determine whether that system is the cause of the problem, and whether disabling the system will either fix the issue, or possibly make it worse.
- adam 8y agoInteresting the production methodology follows Toyota. I blogged about the need for exactly this as I'm convinced in these kinds of situations there are employees working on these projects who know there are issues, but because of culture or pressure to launch, are never heard: https://www.cultivatelabs.com/posts/the-rise-of-anonymous-tough-love-and-not-a-moment-too-soon https://www.cultivatelabs.com/posts/the-rise-of-anonymous-to...
- Waterluvian 8y agoUnrelated: the attempt to prevent me from selecting segments of text is a massive turn off to returning to this website.
- WalterBright 8y ago"the complexity of aviation technology was being pushed too hard and at too great a risk to safety, all in the name of economics." Using automated systems to adjust the flight characteristics has been going on at least since the 707 with its yaw damper, and likely much earlier. There's nothing fundamentally wrong with the 737MAX. An entirely new airplane would entail more risk. Altering the 737, with known and proven characteristics, is low risk.
- mtw 8y ago« There's nothing fundamentally wrong with the 737MAX » This would be like Harley Davidson putting a much more powerful engine in an old bike frame, perhaps because they feel threatened by new technology. However the new engine is so powerful it creates wheelies, and potentially fatal accidents as customers were not made aware they'd need to change their bike driving habits. There is something fundamentally wrong with the 737MAX and how they installed the engines. I'm not an aeronoticaul engineer so I don't know the best solution to minimize the instability. But they certainly should have tried out more configurations, different wing shapes, done more tests etc. Somehow they skipped all that to get more $$
- kayfox 8y agoThe new engines are not that much more powerful (NG: 120kN, MAX: 130kN max thrus), its that they are physically larger. The issue (nose up tendencies at high power settings) was an issue with the 737 Next Generation as well, its just more prevalent with the Max. Also, nose up tendencies at high power settings is a known issue with all jet aircraft that use underslung engines.
- justicezyx 8y ago> Using automated systems to adjust the flight characteristics has been going on at least since the 707 with its yaw damper, and likely much earlier. That's glossy. In our trade, we call that adding another layer of abstraction. And eventually it runs into unbearable complexity and tech debt. Then the thing becomes a disaster. Sure, everyone does this. But that does not make it less wrong or less bad.
- billfruit 8y agoThis year hasn't been a good one for Boeing at all, besides 737 Max issues, there have been major crashes of the 707 and the 767 this year.
- siwatanejo 8y agolinks?
- billfruit 8y ago707 crash in Jan 2019 https://en.m.wikipedia.org/wiki/2019_Saha_Airlines_Boeing_707_crash https://en.m.wikipedia.org/wiki/2019_Saha_Airlines_Boeing_70... 767 crash in Feb 2019: https://en.m.wikipedia.org/wiki/Atlas_Air_Flight_3591 https://en.m.wikipedia.org/wiki/Atlas_Air_Flight_3591
- deleted 8y ago[deleted]
- dotancohen 8y agoNot to mention that due to delays building the SLS, Boeing (ULA) may risk loosing the EM-1 flight to SpaceX. I don't know if the SLS designated (and mostly built) for EM-1 can do the EM-2 mission or other missions, as ULA purpose-builds each previous rocket (Deltas and Atlases) specific to each mission.
- solarkraft 8y agoBy "building" do you mean designing or an actual, phisical rocket?
- dotancohen 8y agoMost of the hardware is already built.
- Panino 8y ago> Every airplane development is a series of compromises, but to deliver the 737 Max with its promised fuel efficiency, Boeing had to fit 12 gallons into a 10 gallon jug. I know this is just impactful writing, but the more I read about the 737 Max, the more I feel that the business decisions behind it are somewhere in between Intel speculative execution and "fly fast and break things."
- kccqzy 8y ago> A warning light that would’ve alerted the crew to the disagreement wasn’t part of the added-cost optional package of equipment on Lion Air’s 737 Max aircraft. I'm not an aviation expert, but why should something that seems as important as an indicator of system malfunction be an optional package instead of builtin?
- dangwu 8y agoI agree with you, but cars have optional packages for warning lights for lane changes and automatic braking. It’s not that hard to imagine.
- TheSpiceIsLife 8y agoThe first thing I noticed about planes is they are not cars. Seems an analogy that’d rapidly break down.
- Joe-Z 8y agoWell, you want to be witty, but that‘s exactly the point of an analogy: Make things that are different comparable, so you can come to conclusions about thing A even though you only have knowledge of thing B. You might want to try to strengthen your argument by explaining why an analogy between cars and planes can‘t hold (one moves only in „2D“ vs. the other one moves in „3D“ for example)
- zaphirplane 8y agothat 737 costs 100,000,000 a plane crash kills a lot of people The training to drive a car vs a 737 is Hugh
- lozenge 8y agoThey both have alternatives (ie looking around you). What's the procedure for figuring out whether AOA sensors disagree when there's no indicator light? The sensors are probably used in numerous ways by the flight control software.
- mtw 8y agoImagine how it goes for military aircraft. If a Boeing military jet crashes, there's no NYTimes coverage, no foreign governments pressure, no dramatic images of emergency response team around crash site. Maybe just a single family voice, or one over zealous Pentagon officer asking questions. But if Boeing doesn't even acknowledge risks after a phone call with Trump, I can imagine Boeing always claiming their military jets are the safest aircraft ever.
- duado 8y agoSafety isn’t as high a priority for military aircraft, except in that losing an aircraft is expensive. Military pilots know that they are expected to die for the mission if necessary.
- tialaramex 8y agoSuicide is not part of conventional military doctrine. Pilots are tremendously expensive and take time to train, so they are not expendable. One of the things going badly wrong for Hitler by the time of the Normandy invasion was he was running out of trained pilots. Factories can build ten more planes when you lose ten per night, but your pilot training can't replace ten men overnight regardless of whether those men are dead or in POW camps. The RAF was losing planes too of course, but mostly in friendly territory, so it kept getting the pilots back. Put them in a new plane and you've kept all that valuable real world experience.
- greglindahl 8y agoThis is incorrect: I read about military jet crashes in the NYT on a regular basis, and occasionally the military grounds an entire model of aircraft.
- solarkraft 8y ago> even acknowledge risks after a phone call with Trump Here is how I imagine such a call. "Oh, our planes are safe, Donald. Who's a good boy, Donald? You are! Good Donald!"
- burfog 8y agoI wonder what design choices were considered and rejected. Was there a missed option that would have been better? Numerous possibilities pop in to mind... The rear landing gear could have been made to extend more, by telescoping or folding. The rear landing gear could have been attached more outboard, letting it be longer without the wheels colliding in the middle. Perhaps something else would need to move a bit to make room. The rear landing gear could have been stowed as the B52 bomber stows landing gear, asymmetrically with one going in front of the other. This would let it be taller since it would be able to cross over the midline of the aircraft. An engine could be flatter if it had two turbines side by side. The cost of engine removal is still low since the aircraft still only has two engines to remove, and the pilot training is the same because there are still only two engines to control. Really, that isn't a quad-jet. Letting the fan portion of the engine peek up over the wing is an interesting thought.
- pauljurczak 8y agoThe primary concern was fuel efficiency, which is proportional to the diameter of turbofan engine. Two smaller engines would be less efficient. The same with turbofan airflow hitting the wing.
- burfog 8y agoTwo smaller turbines can have the same frontal area, which is what creates the efficiency. It's total area, not diameter. Well it is the amount of power per unit of frontal area. Turbofan airflow already hits the support structures for the engine. Everything is a compromise of course. Tossing a bit over the top of the wing could be beneficial, with the impact of the wing being less harmful than the alternatives.
- pauljurczak 8y agoThere is a long list of errors and omissions, which contributed to these accidents, but the bottom line seems to be software development malpractice. MCAS system was designed by Boeing and certified by FAA to keep operating with wildly diverging data from two AOA (angle of attack) sensors. Reports indicate that AOA was the only sensor type MCAS was using. There have to be at least 3 AOA sensors to have some level of reliability in case of a single sensor failure. MCAS should turn itself off in case of large difference between two AOA sensors readings. Whoever wrote and certified that code bears at least some level of responsibility.
- lucio 8y agoAgree. Not having 3 sensors is an objectively bad decision. Why did they keep the system on with diverging data? It will be nice to know what are the risks when MCAS is off. Maybe x% of pilots used to the old 737 consistently stall the plane on the simulator.
- planteen 8y agoThe system does not necessarily need triple voting. Many aerospace systems are only primary and redundant. There are two highly trained human pilots aboard who can detect and isolate faulty equipment. And my guess is that these high level software requirements originated with an aerospace systems engineer, not a software engineer. Clearly that high level requirement was flawed (especially in a human factors sense), but we need to remember that passenger planes are not designed to be fully autonomous. It seems only one AOA sensor is currently used by software. The update will change that. "The company said it will change the MCAS software to give the system input from more than one AOA sensor. It will limit how much MCAS can move the horizontal tail in response to an erroneous AOA signal. And when activated, the system will kick in only for one cycle, rather than multiple times." https://www.seattletimes.com/business/boeing-aerospace/investigators-find-new-clues-to-potential-cause-of-737-max-crashes-as-faa-details-boeings-fix/ https://www.seattletimes.com/business/boeing-aerospace/inves...
- pauljurczak 8y ago< change the MCAS software to give the system input from more than one AOA sensor That's even worse than I thought. The data from both sensors was being logged. Some reports indicated cases of huge discrepancies (20 degrees) between sensors. It is incomprehensible to me that MCAS ignored the other sensor. The lawyers will have a field day with that and in this case I say: go for it!
- charlesism 8y agoBoeing CEO Dennis Muilenburg reportedly spoke with President Trump earlier Tuesday, urging him not to ground the jet. Great priorities there, Dennis! /s
- Jabbles 8y agoHow much of this is hindsight? The article seems to suggest that the 737 Max is poorly designed and incorrectly certified. Is the system really that broken? Who knew? Could anyone have known? Are other aircraft similarly flawed?
- pauljurczak 8y agoAnother great article on this subject: https://www.seattletimes.com/business/boeing-aerospace/failed-certification-faa-missed-safety-issues-in-the-737-max-system-implicated-in-the-lion-air-crash/ https://www.seattletimes.com/business/boeing-aerospace/faile... Notable points: - FAA delegated System Safety Analysis for MCAS and many other certification steps to Boeing engineers (what can go wrong with corporations policing themselves?) - Political pressures on FAA resulted in signing off on some certification steps before they were completed - Actual limit of MCAS’s command was not known to FAA, 737 MAX operators and pilots - MCAS failure was miss-classified as a “hazardous failure” instead of “catastrophic failure”, which would require redesign - MCAS was not even mentioned in flight manuals