This is the correct move. Airline crashes are so rare that two crashes of a new model within 6 months of each other must be cause for grounding flights.
The fact that Boeing cut as many corners as they did to bypass mandatory training just adds more smoke to the fire. When the dust settles on this episode I won't be surprised to learn that Boeing (and FAA regulators) is found completely at fault for engineering shortcuts to save costs on re-training.
> This is the correct move. Airline crashes are so rare that two crashes of a new model within 6 months of each other must be cause for grounding flights.
I agree. It seemed like the FAA was taking a position best described as "innocent until proven guilty." I think that's great for the US criminal justice system. I think a better approach for air travel safety is "abundance of caution." I have no direct experience in this field but it seems to me that the plane should be grounded out of an abundance of caution until we know more.
Edit: FWIW I used the phrase "abundance of caution" before I read it in the article.
Question: is it realistic to expect cops to know exactly what law someone is breaking before they decide to arrest them? Like I get that in an ideal world this would be the case, but humans only have so much memory. Is it unreasonable if a cop arrests someone because it seems the person is doing something that warrants it, but then later fails to find an actual crime they can charge them with? i.e. Would we be better in world where cops only arrested those whom they could immediately charge with a crime?
Cops arrest people for all sorts of reasons. They don't have to have proof of a crime; suspicion is enough. They don't immediately have to charge them with anything, and they can first question you. If they decide not to charge you, they can keep you in custody for a couple of hours at most.
Then again, in Guantanamo Bay there are people held in custody for many years now without any charges, so these rules can be bent pretty far in the right circumstances.
Planes aren't criminals or even citizens, though. But to translate this to the 737 Max situation, when something seems to be wrong it seems entirely reasonable to ground planes in order to investigate the situation. But there should be a limit to that grounding, and a permanent ban requires some actual proof.
Of course keep arresting people for no good reason, people lose their trust in them.
In practice, cops in a position to arrest people on their beat are generally arresting a series of people for the same thing over and over again, and eventually learn the details of what will satisfy a charge.
Mileage will vary based on geography and beat though.
And... I'd admit we saw some charging documents we immediately dismissed from new officers, roughly like 'this guy seemed shady and was near a crime.' We'd lay into them for that though, they'd eventually seem to figure it out.
You'd have to ask a lawyer if this would fall under probably cause - i.e. a police officer is allowed to arrest someone if they have a "reasonable" suspicion that a crime was committed, and then the prosecutors decide whether to bring charges. It's not clear to me how a court would view an officer being mistaken about the law in specific ways.
This depends upon where you are doesn't it? In the UK the grounds for arrest are "reasonable suspicion" in the US isn't it "probable cause"? I think that "reasonable suspicion" is similar to 10% certainty and "probable cause" 25% (c/f with "beyond reasonable doubt" which should be 95% certainty)...
I am not a lawyer. If anyone is in doubt I suggest speaking to a lawyer!
"Probable cause" is defined using the word "reasonable" in lots of sources. The root of any UK/US difference is more likely related to drift in precedent over the last couple of centuries than to any precise difference in the meaning of words.
I don’t think the parent comment is about arresting. But holding someone without bail until a trial has concluded where by it is deemed that the person is a possible risk to society by being released until trial. (I think)
Effectively yes, you can do that as a cop in most justice systems if you can dress up the "seems shifty" in a bit more concrete terms.
But if there is nothing to back it up, the guy will be realeased very soon, and if you do it repeatedly, you'll eventually get problems (and rather quickly and seriously if you lied and it can be proven).
A little bizarre to see "them" followed by "he"...
I guess the question here is what about him makes him seem shifty to you. One would at least hope his skin color would not be factoring into that and that your judgment would have been the same for anybody else exhibiting the same behavior.
Great point. Criminal Justice is about erring on the side of caution of imprisoning people wrongfully. Its why there's a difference between arrest and imprisonment.
Boeing is the single largest exporter in the US. The idea that we are going to seriously punish them is laughable from a political standpoint, regardless of what the regulators have to say.
Isn't the alternative an abandonment of the 737 max 8 series from international carriers? The US currently has the largest aviation market but it's growing globally. Airbus has the 320neo and 220 which are direct/close competitors.
Remember the 737 has been slowly growing each generation: the A220-100 doesn't compete with the 737 MAX at all (it's smaller than the 737 MAX 7, and the MAX 7 has only 61 orders, out of over 5000 total orders). It provides a possible replacement for the A318 and 737-600 (but also neither of those sold well either!); it's biggest competition is probably the E195-E2.
The A220-300 competes with the A319neo and 737 MAX 7 (and the A319neo isn't selling any better than than the MAX 7).
I don't think really an abandonment is on the cards: too many fleets are too heavily bought into the 737 family, and the cost of migrating away is real. By way of comparison, the A320(ceo) hardly had the best of starts to its life either with the Air France Flight 296 crash (which while different, still wasn't exactly good press!).
Then the interesting question is whether airlines would punish them by forcing better terms or even lawsuits, and would shareholders likewise punish them by selling the stock.
I'm fairly sure knowingly selling defective airplanes involves some liability and breach of contract issues even without criminal charges. No need for the FAA to punish Boeing, but I expect them to feel the weight of public opinion.
Grounding aircraft for unexplained mechanical failures is the norm.
Following that, the problem is not finding who is at fault but how to prevent it from happening again. The first step to getting the aircraft ungrounded is often to update the flight manual and decrease inspection time so it can be flown safely with reduced capabilities. The root cause is fixed later.
Aviation regulatory bodies are normally not into finger pointing. Traditionally, the customer pays for everything, even if it is not their fault. The reasoning is that it is one less incentive for the manufacturer to hide defects. No doubt that legal battles will ensue but care is taken to keep lawyers out of the technical process.
It's sad that Boeing tried to cut so many corners, but absolutely baffling that the FAA went along with it. They squandered an enormous amount of trust by doing this. I wonder what the long term effects of that loss of trust will be.
And even if they fix the problem and pilots get more training, it's still likely to hurt 737 Max sales; it seems likely they cut those corners because having the Max count as "just another 737" that didn't require extra training, was a major advantage to airlines. When airlines need to retrain their pilots anyway, they might choose different planes in the future. And they may be less likely to trust Boeing and the FAA when they claim a new plane model won't require extra training.
Then again, I don't know the airline industry. Maybe it just blows over with no long term effects.
I'll happily blame anything on this evil administration, including this, but the corporatism which led to these deaths predates the American fascist assumption of power.
I think we should be careful to look wholistically at this. Will grounding the plane cause more people to drive? Driving is so much more dangerous than flying even if there’s a MAX crash every 6 months (doubtful). How many more people will take connecting flights — the danger is in the take off and landing after all. I don’t have the answers, I’m suggesting this isn’t a straightforward decision. Humans have an amazing ability to overweight incredibly unlikely outcomes with severe consequences.
Some napkin math. 150,000 flights, each with 172 seats (based on the American Airlines 7M8 configuration, which is admittedly tight). That's 25.8 million journeys. Two accidents, let's that's ~350 deaths. Your chance of dying on any given journey is therefore 0.00135% (four nines to live).
You've got a 0.0167% chance of dying [1] for every 10,000 miles driven. Let's assume that each 7M8 journey averages 2500mi (generous, a transcontinental average). A linear projection tells me that's a 0.004175% of dying in an equivalent car ride.
You're still 3X safer on a 7M8 than you are in your car.
Now, by no means should this be taken to say the planes shouldn't be fixed or that Boeing should "get away with it." However, grounding all these planes and pushing people into a less safe form of transit may actually end up causing more harm than allowing the planes to fly with a fixed, short schedule to resolving the problem.
> "Driving is so much more dangerous than flying even if there’s a MAX crash every 6 months (doubtful)."
I'm not sure that's correct. Let say there's 350 MAX aircraft in service, flying 5 flights per day on average. In 6 months, thats about 320,000 flights. So a 1 in 320,000 chance of a fatal crash. Let's say the average route length is 1000 miles. That's 1 crash per 320 million miles flown, or 3.125 crashes per billion miles flown.
If we assume an average of 150 passengers per flight, then it's 468 deaths per billion miles for the MAX, compared to only 0.02 deaths per billion miles across all aircraft. [1]
In the US, there are 12.5 deaths per billion miles driven, including pedestrian and cyclist deaths from motor vehicle collisions.[1]
If it crashed once every 6 months, the MAX would be around 37X more dangerous than driving, and 2340X more dangerous than an average commercial flight in the United States.
150,000 flights, 172 seats per is 25.8 million passenger seat-journeys. Given the type, I think it's fair to say they're at least 1200mi long (why fly a 7M8 on a sub-2 hour flight, when you can just throw a regional jet at it). The whole point of the MAX family is that it can fly further than a normal variant. This is 30.96 billion passenger seat-miles. There were ~350 deaths. This is 0.000000011 deaths per passenger seat-mile, or 11 per billion. This is in line with but still less than driving (12.5 per your data source).
I imagine 1200 miles is short for an average 7M8 flight though, which could make it substantially safer. With 2500 mile averages you get back to that 3X number I cited. It's still no more a death trap than your average Honda Civic (10% safer by your metrics, more by mine).
To your point, it is of course riskier than a different aircraft.
My whole thesis was to ask what effect this will have across the entire population and how will humans react, irrationally, to this news.
There are arguments against measuring crash rates by “number per vehicle miles traveled” and instead by “number per vehicle hours traveled.” VMT is a product of speed and time, and thus a fatalities-per-VMT metric will nearly always show the faster routes to be safer.
But compare spending 20 minutes traveling 10 miles on a local street, vs 10 minutes traveling 10 miles on a freeway. Both are considered equally safe using a fatalities-per-VMT model. But in the former, you’ve stayed safe for a longer portion of your life. (See http://pedshed.net/?p=1050)
Using that metric would make that Boeing far less safe compared with driving.
That argument seems flawed to the point of absurdity. Two extreme examples showcase this:
1) a teleporter with the exact same risk as driving 20min on local streets or 10min on the highway would be the worst thing ever invented. In reality, 100% of people would choose it unless they were intentionally wanting to spend time driving
2) A 100% safe ridable snail would be the ideal form of transit, given that you'd spend your whole life safely trying to get somewhere.
> measuring crash rates by “number per vehicle miles traveled” and instead by “number per vehicle hours traveled.”
there's another issue, which is plane risk is uneven during their journey, so a type that does half the flights but twice the distance on average will end up almost 1.5 times as safe all other things being equal.
a way to normalize that would have to use "number per flights" but then you'd get trains, with their multi-stop journeys, skewing the numbers the other way.
As a traveler, I care about the trip, not the time nor the distance. If I take this trip, what's my probability of dying if I fly it versus drive it.
Airplane travel have fixed segments (takeoff and landing, ascent, descent) and variable segments (the coasting phase that varies by distance traveled). Car travel is only the variable segment. Hard to compare apples to oranges.
On the flip side, if the plane is intended for long flights, do you think people are just going to drive 1200+ miles and incur the gas, the additional time, a hotel stay or a few?
Some trips may be made using older aircraft. Some trips may not be made at all. But I think assuming a 1:1 correlation with driving is a bit silly.
A very good point, although, my fear wasn't that people would replace 1:1 7M8 flights with a roadtrip across the country, but that grounding an entire plane type would cause people to replace short flights with long drives. I suppose planes falling out of the sky may do that too :)
Also, more broadly, you have some degree of control over dying in a car. Like the odds of dying on the road while driving a modern safe car, legally and carefully, would be lower still again. Airplanes we cede all out control over safety to the airline / pilot and manufacturer.
This would be true if you were on the car alone. Unfortunately we all share the road, so it only takes the most dangerous person on the road to ruin your safety.
Even so, just by following road rules, driving sober and having a well-maintained car, you likely go to the bottom decile in car-related risks. That much is definitely under your own control.
Have you examined the actual outcome of grounding this model of plane?
I would think at least some people are driving instead. US airlines run at a pretty high utilization, grounding dozens of planes isn't going to be easily absorbed into other flights.
Grounding a newly release airliner is not new. It's only news because of the two crashes and 300 victims. I'm pretty sure these airlines are careful and still have some of the older 737/A320 that these MAX were supposed to replace.
Issues with new airliners and engines -specially engines- are not rare at all. So this sort of grounding is not rare: see 787 first grounding (battery issues), current partial grounding (Rolls-Royce Trent 1000 issues), or Pratt & Whitney ongoing issues with the A320NEO engine (PW1000G issues).
You can imagine the sort of clusterfuck when PW needs to produce 60 engines a month for Airbus, only manages to build 20 in its factory... but need to send these 20 engines to replace already delivered engines because they are defective. The situation has improved a lot lately, but 2017/2018 were tough...
Only the A350 introduction has so far been relatively event free. Probably because the Trent-XWB is a derived from the Trent 1000, so the 787 took care of the teething...
> Only the A350 introduction has so far been relatively event free.
I am biased on this since I have spent a couple of years working on the development of A350XWB systems (and only marginally contributed to other programs) but I always had the feeling that, after the trauma of the A380 (rampant production issues, lengthy delays and management mishaps/stock fraud), the focus for A350XWB was put on accountability at all levels.
This might not be sustainable for a large corporation but retrospectively, that seemed to have had the desired effect at least for this particular aircraft program.
Maybe! Looks like there've been 350 deliveries so far [1]. Are that many planes available on short notice to replace them? Airlines generally operate with 80% load factors, it'd be hard to just re-shuffle everyone.
The grounding and reaction may also shake people's faith in air travel in general, causing them to drive more even if planes were available. Bruce Schneier has a good write-up on this effect post 9/11 too. Humans are terrible at dealing with this kind of thing.
The reality is you're much more at risk in your Uber ride to the airport than you are aboard the 7M8.
I think in practice more of the flights will be replaced by other flights or not travelling than driving 2500 miles.
Commercial flying is safer on average than driving, but that's because of, not despite the extreme approach to safety concerns. (General aviation is actually substantially more dangerous than driving)
Maintenance deferral is not an option (unless they're electively carrying out maintenance checks well ahead of OEM-specified intervals) and type-rated crews landing in unfamiliar territory happens on a daily basis and certainly isn't a risk factor comparable with a [possibly] flawed aircraft. If the delay's long enough to actually see parked aircraft brought into service, it'll largely be the same crews flying older 737s anyway.
Mostly people will just cancel their holidays or agree a teleconference because getting flights on that route at short notice is too difficult.
> type-rated crews landing in unfamiliar territory happens on a daily basis and certainly isn't a risk factor comparable with a [possibly] flawed aircraft.
Flying in/out of unfamiliar territory is a known risk. Whether the 737 MAX series is higher risk or not is an unknown risk because of insufficient sample sizes.
Hopefully some statistician will start tabulating P values so we can see if the confidence intervals overlap or not. Treat this situation like a new "better" drug for X where 2 users died in quick succession. Is there enough evidence to take it off the market or not? AFAIK, nobody has (yet).
>If the delay's long enough to actually see parked aircraft brought into service, it'll largely be the same crews flying older 737s anyway.
Sorta. On a Canadian airline, Westjet, the MAX is flying routes that are too far for the regular 737s without a fuel-stop (by my estimates). I'm booked for such a flight in 2 months. I'll get to learn what happens. I would have been happy to fly the MAX8 based on the current lack of evidence for grounding.
Of course, the other thing to consider is how many more people will drive due to a loss of trust in the FAA and airlines over the failure to ground the plane once it's percieved as unsafe.
"I could drive or fly...oh, no, but what if they try to put me on a 737 Max? I better drive."
No, most people don't pay that much attention, honestly. "Drive or fly? Hm... that plane did just fall out of the sky right, planes freak me out, let's just drive." This is an excerpt of a conversation I've had with friends after the MH crashes. I had to explain to them planes generally don't get shot out of the sky or just disappear and that in spite of this all, flying remains safer than driving.
People pay attention to things like this. My kid is flying to Denver in a few weeks and was looking to see what plane type it was. An acquaintance is heading west for work and the first question was ‘Max 8’?
I see what you’re saying, but there are intangibles that are hard to factor in. For example, a big reason that air travel is so big an industry is precisely because it is so safe. But that image could get tarnished very easily, at which point you would see a sudden and large drop in paying customers (think 9/11). Consequently, grounding the planes until everyone can be certain of the cause and the remedy is in the best interest of the entire industry (although not great for Boeing in the short term).
Why will grounding the plane cause more people to drive? It does not have large enough share of existing planes to cause significant rise in prices to make people choose driving. Especially considering that it is used for long distance flights, which are more likely be replaced by train instead of car.
Flying is only as safe as it is thanks to regulations written in blood. I don't think flying today versus driving today is the right comparison to make, rather flying today versus flying in a decade. If we allow leniency on the basis of alternatives to flying being more dangerous now, improvement of flight safety may be squandered so that the safety of future transport as a whole is reduced.
I also think these regulatory bodies have to make grand gestures, at times, to reassure the bags of blood and bones that get on planes in a way that statistics do not.
> Let's assume that each 7M8 journey averages 2500mi
Let's then also assume that people are not commontly drive transcontinental distances.
Your calacluations are interesting but all over the place. E.g.:
> How many more people will take connecting flights — the
> danger is in the take off and landing after all
So in this case distance does not matter. How does car safety compare to airplanes in terms of number of trips?
Anyway, the biggest problem is assuming that all grounded flights will be replaced by driving. Either the flight will use different aircraft or the trip is cancelled in majority of the cases.
The holistic view is rather that the only reason we have such safe aircrafts so you can get such nice numbers is because there's very well crafted procedures for handling crashes.
Reacting strongly when those procedures seems to have missed something is important not because of the crash itself but because the process is important. Could the same oversights lead to additional fatalities is the question, the robustness of the boeing is a minor point.
Well nobody is proposing a free pass here. Of course they'll all need to be fixed, and ASAP. I'm just saying, it's no more a death trap than your average Honda Civic so it's probably okay to let them stay up in the air, depending on what the confounding external factors end up being.
Cars kill people primarily due to human error in judgment or lack of attention. Mechanical or software failures causing fatalities are the overwhelming minority of cases.
Remember how big of a deal the Toyota accelerator pedal recall was?
There was never any evidence that a software glitch caused sudden unintended acceleration in Toyotas. The problems were caused by defective floor mats and driver error.
I have a family trip booked next month on Southwest, who has many 737 Max 8. I'm relieved that they won't be able to use it now. I'm still expecting my flight to happen, Southwest and Boeing will have to figure out how to get the plane.
Southwest was actually grounding these flights yesterday (Tuesday) before the FAA decision. Source: flight was cancelled along with multiple other 737 MAX flights out of SJC yesterday.
They had no choice. When no other major regulator would stand with their position, and the public didn't wish to fly on the Max 8, the position became untenable.
After the flight data recorders are recovered from the Ethiopian Airlines accident they could reevaluate if it turned out to be something else. But this seems like a rational safety first position given what we know today.
Hopefully Boeing's April patch and mandatory additional training mitigates the issue well enough to resume normal flight operations.
Remember all the early A320 crashes? Do you worry about stepping onto an A320 now? Unless the problem turns out to be far deeper, I suspect that this, too, shall pass.
"an a320 crashes every two years" sounds quite different than "a brand new 737MAX crashes during take off every 6 months because of the faulty sensor thingy".
Also a320 family of 8605 aircraft took the life of 1393 passengers in 30 years, 737MAX is at %30 of that in two years and 350 aircraft.
737MAX accidents look very brutal and specific. It doesn't look like "ironing out imperfections" but more like "this plane is broken, it falls off on take off" - regardless if that's the case, people see a pattern here.
It's not fair to blame the plane at all unless you're sure the crash was the plane's fault, but that isn't stopping most of the people in this thread from doing it.
Airplanes don't have the right to a trial of their peers with presumption of innocence.
Two crashes within six months is very abnormal. Abnormalities are evidence of problems. Airline regulators are tasked with keeping people from dying, not with protecting manufacturers' feelings.
Those three crashes had one thing in common: terrorism.
These two crashes have one thing in common: brand new planes.
Unless you know of an islamist terror organization that has a grudge against Ethiopian desert wilderness, I don't think terrorism is a more likely common cause than the brand new airframe.
Yes but my point is that people don’t avoid the 767. Look upthread please, this whole sub thread is about whether these incidents will cause consumers to avoid 737 Max planes in the future.
My (apparently very controversial) opinion is that we don’t know enough to predict that now, because we don’t know what caused the Ethiopian Air crash yet.
People never avoided the 767 because it was clear all along that the crashes had noting to do with the plane.
People are avoiding the 737 MAX because given the current information it definitely could be a problem with the plane, in fact the information we already have from the first crash makes it look like it's very likely to be a problem with the plane.
> People are avoiding the 737 MAX because given the current information
Again: the topic here is predicting long-term damage to consumer confidence. I understand what is happening right now.
The entire 787 fleet was grounded not more than a few years ago due to battery issue. How many people actively avoid 787s today? Long-term consumer trust depends not just the root cause of an accident, but also the perception of how it was addressed. As the GP correctly points out, the 767 (and all other planes, and security screening procedures) were redesigned to protect against the type of attack that succeeded on September 11.
> It's not fair to blame the plane at all unless you're sure the crash was the plane's fault
I'd say "unless you have some indication that it was the plane's fault". Otherwise, agreed: 2 crashes per se tell you nothing about the safety of the plane; it could've been a terrorist attack or a suicidal pilot or a missile.
It's two crashes under similar circumstances, with no indication of such an external event, that justify suspecting the plane.
> It's not fair to blame the plane at all unless you're sure the crash was the plane's fault
Since we aren't talking about assigning criminal penalties to the plane (for one, because its fairly well destroyed, and for another because it wasn't the kind of thing subject to such penalties in the first place), the criminal standard of proof ("beyond a reasonable doubt" -- which still falls short of actually being sure) is inapplicable. In fact, given the minimal consequences of blaming the plane in the discussion in this thread, its probably fair to do so if there is any reasonable basis for belief that that the crash was the plane's fault. Its certainly to do so if the preponderance of the evidence as yet reviewed by the person doing the blaming suggests that, even if it is a fairly weak conclusion that a very small amount of additional evidence could reverse.
I don't object to this line of reasoning, I object to the idea that this line of reasoning by itself, as known today, is sufficient to predict that the reputation of the 737 Max is permanently damaged in the eyes of consumers. That's the context of this subthread, starting here:
>"an a320 crashes every two years" sounds quite different than "a brand new 737MAX crashes during take off every 6 months because of the faulty sensor thingy".
If you cherry-pick the time interval, you can say that basically all planes crash once every hour.
It was almost 1 a year for the first 5 years, but that is still less than 25% of the current Max-8 rate.
Edit: Max-8 had first flight in 2016 is in service since early 2017, so the crash rate over that period is roughly identical with the rate for the first 5 years of the A320. We just have a set of two closer together recently. Not enough data to form a statistical basis of course.
This should be normalized to tue number of flights (if the problems are related to starting/landing) or to flight hours (general problems that might appear mid air)
Time is not a very usefull thing here, as number of active aircraft and flights will be very variable.
Agreed. I don't think they're unsalvageable, but they're definitely unsafe in their current state, and trust will need to be rebuilt (a slow process). Boeing is to blame for most of this because of their design decisions, too.
Yeah I dunno about that. Sure they don't care about airplane model in general but this is fast becoming a known name and associated with crashing. In the past few days I've had my in-laws and my own grandma asking me to help check their planes for booked flights. You just need a bit more of the tabloids to run on it and this model plane is finished in the public's mind.
I think this is natural because it's a major news story right now.It seems likely that some upgrade will be made to the planes to address whatever issue they conclude they have, and once that's done and the planes are in the air again people will soon forget about it all.
I must be very unique then. As someone who flies often and cares about making it there, I _have_ been booking recent flights to not take MAX aircraft, even at the inconvenience of multiple legs.
I have no direct experience with aviation software, but if it's similar to other highly regulated environments, a SW "patch" is not "simple", possibly it means weeks/months of regression testing and validation, justification for it need, etc...
But that's the thing, the 737 max isnt a revision of a model number. It has a very different airframe with different flight characteristics from other 737 models.
Boeing used software to override and reinterpret pilot inputs so that the airplane behaves as if it were a 737, in order to cut costs on retraining. When that software fails, the pilots are suddenly flying a totally new airframe that would normally require additional certification with 0 experience.
Sorry to go on a tangent, but if they were going the redesign the airframe anyway, why didn't just make the plane aerodynamically stable with the bigger engines (make landing gears longer?), instead of lifting the engines and using software to compensate?
Sure. But my point is that the name is easy to forget. It's not a top level brand like 737 or 787. It's a variant. People will write the information off as essentially trivia, because it's just one variant out of "how many?"
that's exactly what airbus does... there are a set of "laws" that govern flight at different stages of flight "normal, ground, flight, flare, alternate 1, alternate 2, direct, and mechanical" quite complex systems, that.
And this is what contributed to the crash of AF 447.
That said, I prefer either the older boeings, with minimal computer interference when hand flying or the Airbus approach. Because Airbus at least appear to know what they are doing.
No. The intended behavior is a nose down nudge every 10s only when a) exceeding a certain angle of attack b) above a certain altitude and c) when flaps are retracted. It's second guessing only at a particular edge of the normal flight envelope to prevent it from departing that envelope.
And all the various layers of protections in fly by wire airplanes do that - they second guess certain inputs to prevent edge cases. But in any case the input is going through software abstraction. Any apparent directness is part of that software behavior.
I'll be interested what the software update due at the end of April entails exactly. I think every airplane should get the angle of attack sensors disagree indication, standard.
An intrinsically dangerous plane that needs either much more careful piloting (hard to sell...) or software assistance (bad idea) should freak you out even more.
Long term public opinion impact would likely be much smaller if the FAA had lead the grounding, not lagged behind: "some sub-variant of a model iteration on hold for investigation" would have been merely a footnote only those directly affected would remember a day later. But this slow-motion wave of country after country changing their minds with ever increasing drama "what will the FAA do!", this is quality news-tainment. I know that hn readership is not representative (the intersection of aviation geekery, software engineering and high stakes UX: golden), but it's quite a bit of a headline elsewhere as well.
No. The 737 Max introduced a fundamental design weakness that was implemented for cost efficiency reasons only. The center of gravity is towards the rear, which makes the plane tend to tilt backwards, and requires an automatic system to compensate for that https://www.seattletimes.com/business/boeing-aerospace/faa-e...
My understanding is that the issue is more one of the centre of thrust (of the engines), which is now further away from the centre of gravity, giving rise to a larger momentum.
It confirms what I've read about this issue so far. But this article is from the previous crash. If this was already known, why hasn't it been fixed? Why haven't pilots received additional training to deal with this?
There are a ton of planes with a better flight/crash ratio.
380 A340 where build since 1991 almost exactly as much as the number of 737 Max built (376). Not one fatal accident in almost 20 years for the A340 versus 2 fatal accident in 2 years for the 737.
My point is that all 737 Max pilots flying today are briefing on the issue and hyper-vigilant, while the Airbus pilots doze in their cockpits in peace.
The point is that all legally licensed 737-type-rated pilots are currently legal to fly the 737 MAX line, no questions asked, no training needed. (As far as I know.) The plane should be moved to a new type certificate and all its attendant requirements, seems to me.
I can’t legally be the PIC (pilot in command) in a Citation 525 (“CitationJet” or CJ) despite it being nearly identical to the 550 (Citation II or Bravo) I can, in most ways that I can tell matters. I have copilot time in both and PIC in the 550 (and related models). The newer plane is even easier to fly, frankly, and has some nice safety features for engine failures. I have to get the training and certification (and recertification every two years) to legally be PIC in the newer Citation, though.
My limited understanding is that the aerodynamics and flight characteristics of the 737 MAX are quite different than the older 737-800 - let alone the even older second (or even first) generation 737s. The memory items may be different. That alone should have mandated a new type certificate in my non-regulatory expert perspective.
Flight characteristics are reported to be the same in the normal flight envelope except at high angles of attack where the new engine nacelle actually produces lift which translates into a further pitch up - but I have no idea how aggressive this is. But it's enough that this is why MCAS exists.
I'm certainly concerned whether MCAS is both working as intended, and also failing safe. But my more immediate concern is like yours: when MCAS is effectively disabled in the normal course of troubleshooting runway trim by setting stab trim to cutoff, now you have a plane that has different stall behavior than you're type rated for! Flip those switches, now you need a different type rating! Of course pilots can learn different stall behaviors and avoidance for a new type, we don't need abstraction to do that for us when we know about it and have trained for it. Stall avoidance is fundamental make+model knowledge, but it can be non-obvious and making it obvious and deliberate is what the type rating is about.
So yeah we might actually end up in the very curious case where either Boeing, or FAA or NTSB are all: this is going to require a type rating afterall. The very thing the airlines in particular want to avoid.
It seems to me the in-cockpit "aoa disagree" option needs to become standard by AD. MCAS only takes input from one of the two alpha vanes, so if it gets bogus data it has no backup source. Meanwhile the pilots have no indication the two vanes disagree unless they (apparently) bought that indication feature. Which I think is pretty fucked up if that turns out to be true and relevant as to either cause or solution in all of this.
The solution here is going to be to have MCAS automatically disengage when the two sensors disagree, which will change the stall behavior automatically. Airbus has the same problem, and so will any manufacturer that introduces computer augmented flight characteristics in their aircraft. If a component of the computerized flight control system fails, the flight characteristics of the aircraft will change. In fact, Airbus has had a similar crash: in that instance, a pilot was pulling full back on the stick thinking that the aircraft was unstallable, but one of the sensors (airspeed, maybe? can't remember) was disabled (by icing, if I remember) and the aircraft had changed to a different flight control law that didn't have the anti-stall function. Splash.
I don't think the AF crash was a case of that pilot "thinking it was unstallable" so much as not thinking, in the mental state he was in at that point. Even if the plane were "unstallable", pulling full back on the stick like that would not have been the right course.
The problem is that the issue may cause the plane to be unflyable even by a pilot aware of the issue.
The earliest reports said that pilots could avoid this runaway trim issue by knowing to disable the electric trim. Now it sounds like doing that may also eliminate all ability for pilots to trim the aircraft.
Inability to trim make airplanes extremely difficult to fly, the control (yolk) pressures required can quickly become too high to maintain control. Pilots would have to hold something like 1 lb of continuous backpressure for every 6 knots out of trim for the entire flight.
> The problem is that the issue may cause the plane to be unflyable even by a pilot aware of the issue.
That’s partly true, but it’s not the whole story. MCAS and its use to make the MAX 8-9 fly “more like the 737” is part of a longer trend of manufacturers coddling pilots instead of expecting them to behave as competent professionals and treating them as such. They’re effectively opting for a more familiar normal aviating experience, with the tradeoff being longer emergency/exigency checklists and so much more to manage/remember/process when the system malfunctions. With the end-result being that even more experience is required to safely and reliably pilot modern aircraft.
Side note: Disabling trim should only be done as part of a problem remedy, not as part of normal flight.
(Disclaimer: I’m not a pilot. I’ve read for many hours on these issues.)
Something is terribly wrong when the regulator that's supposed to keep people safe is less willing to do that then the company that stands to lose the most from the bad image of a product.
Compare and contrast with Johnson & Johnson's handling of the 1982 Tylenol poison incidents. Tylenol immediately pulled the product off the shelves everywhere out of an abundance of caution and earned a lot of credit with the public. Boeing... yeah.
Just in case anyone is under the presumption that J&J is a good company, that business school corporate responsibility case apparently didn't have a lasting impact on their culture. In recent years, there have been numerous cases of them covering up serious defects in their products while keeping them on sale:
Honestly that's more of a sign of the times. People have gotten more greedy and immoral when running companies. Or just in general, have become complete cowards to admit they fucked up.
No Southwest and American airlines stand to lose the most. Nothing is worse for an airliner than a grounded jet.
As an aside, do you know who actually owns most of the jets for an airliner? Banks like wells fargo and chase. They still expect leasing payments regardless if the plane is flying or not.
> Nothing is worse for an airliner than a grounded jet.
Those airlines clearly think the probability of this is pretty low or they would have make the call to ground those planes on their own, but a jet that smashes itself into the earth and disintegrates because of a faulty sensor is probably even worse than a grounded jet.
Not quite because the Airline can turn around and sue Boeing so there is some recourse. Furthermore, people aren't blaming Ethiopian airlines they're blaming Boeing, so the reputation damage to the airline would likely be minimal. The reason why they can't easily sue Boeing over the grounded airplanes is that they don't own them, the banks do.
Of course they're crude, however the fact remains that with very few hours in the air, 2 737-maxs have crashed in similar circumstances, both under 6 months old. If this doesn't raise concerns, what does.
Traders operate on all kinds of time scales, and most trading is done based on algorithms that account for the fundamentals more than of-the-day news. It's likely that holding SW is good for the long term as people make more money and continue to fly more.
My company sent me on gig to a petroleum pipeline once. Gig was a result of an accident where a couple of people were burned alive in their homes when the pipeline exploded. Maintenance guy I met said one the engineers went down to the accident site to supervise. That night came back to the office, sat down and threw up on his desk.
I certainly couldn't have been the only one to look at the airline I'm about to fly on and check that they didn't have any of the Max 8 variants in service.
I bet American and Southwest were receiving phone calls from customers cancelling their flights.
Supposedly the profit margins for discount airlines are pretty slim, so if they can't fill all the seats what's the point? What's bad is that they had to wait for that to happen before they took action. It just makes it look like they'd choose profits over safety every time... as long as they can keep making profits.
Looks like SWA at least was very proactive already after the first crash. Supposedly their fleet of 737Max has been retrofitted with additional cockpit displays for (faulty) AoA values. And they have afaik also extended pilot training.
Not sure if thats all to it. It seems rather curious that US grounding the aircraft (and Boeing advising to do so) right after about a day or so after black boxes being found. Also, Ethiopian authorities issued a statement about the pilots reporting flight control issues rather than any external factors. I wouldn't be surprised if they already have priliminary evidence that there's an issue with the aircraft.
Good lord, this has been such a disaster for the FAA’s image. Slower than everyone else to ground the plane and they project the appearance of being susceptible to political winds. Not a good look.
A plane crashes and kills over 300 people, in two separate incidents, in an industry where even minor crashes are rare, and you think the grounding of the planes is "political"?
Except your timeline is wrong: China was the first to issue a ban, followed by Indonesia. Australia and various European as well as non-European countries followed suit, and eventually the European Aviation Safety Agency.
FAA is not in the business of operating based on unsupported assumptions. The investigation for the second crash is not complete and a root cause is not known.
If a third 737 Max 8 were to crash before a root cause of this crash can be determined, would you then say it's a prudent move to ground them all? What about a fourth? Fifth?
Is your position that any grounding of the planes is unjustified until the full root cause is determined, or that "only" two crashes isn't enough to justify this action?
While I would always rather understand root cause -- and it's absolutely essential to get there eventually -- the world is full of imperfect information and assumptions are sometimes all you have.
One inexplicable crash is not a case for grounding, no; otherwise the (incredibly safe) 777 would still be grounded because of MH 370.
Regarding the 737 MAX now, the prior Lion Air crash is reasonably well understood. It has exposed some fundamental weakness and questionable design choices, but the plane was still deemed safe to fly.
Thus, what we have is one unexplained crash. Why should it be grounded?
(Having said that, I'm avoiding the MAX as far as I can. But that's based already on the Lion Air crash. So, I argue that it should've been grounded after Lion Air became understood, or not at all.)
We have one unexplained crash where early reports about what happened /strongly/ match the circumstances that brought down the LionAir flight. We also have hundreds of public complaints from pilots across the United States of similar unexpected nose down behavior from 737 MAX airplanes.
Bullshit. Anyone who deals with or tries to deal with the FAA will tell you they deal with all kinds of unsupported assumptions. For instance, medical certificates are denied all the time for people who admit to having taken an ADHD drug when they were a kid, even if they only took it once or didn’t want to take it. Why? “An abundance of caution,” which is a frequent cause for actions the FAA takes.
> "The investigation for the second crash is not complete"
After two crashes in such a small amount of time, the investigation doesn't need to be complete. The planes should be grounded until proven safe, not flying until proven unsafe.
Somehow Americans always play the victim card. The airplane is maybe dangerous but nope, grounding it is a political move? I just wish to see the comment section of the plane was Chinese.
Not how it looks from the rest of the world I'm afraid. More, US didn't want to ground plane built by US manufacturer...
... i mean, honestly all we're doing out here is sitting back with a bag of popcorn and channel flipping between the UK parliament on Brexit, and Trump on twitter. And they say there's nothing entertaining on TV any more...
The problems with the plane have been known for a while, so much so that there is a high priority control software patch in the pipeline. The design as it existed is inherently unsafe as it relies too heavy on the input of a single sensor without any sanity checking, redundancy, or correlation with other sensor data.
Also, the FAA makes precautionary changes before it knows everything, it has routinely issued emergency airworthiness directives before investigations have been complete.
An interesting point was made by an airline pilot in one of the plane forums. It appears that Max 8 with full trim deflection down doesn't have enough controls authority to recover (at least in the syms). Thus, the trim issues followed by disabling the trim can lead into a situation when pilots can not recover the plan from steep descend. Of course, this is not necessarily what have happened in real life and we need to see the data.
Pilot here. Correct, in most aircraft that incorporate a trimmable horizontal stabilizer, elevator authority will be insufficient to counteract the aerodynamic effects of a the entire tailplane having deflected through a certain point. Thus it is important to quickly recognize and correct a runaway trim situation.
Of even more significance is that is currently unclear if it is even possible for a pilot, once it has disengaged the trim motors (following faulty commands from MCAS) to manually correct the trim as per Boeing procedure [1].
The problem lies in the fact that it makes a lot of sense to haul back on the yoke as hard as you can if the nose starts dropping. Elevator upwards deflection loads the tailplane aerodynamically in such a way that it becomes harder to trim the tailplane in the required direction. Called colloquially a yo-yo maneuver, you are then require to "offload" the tailplane (think - push yoke forward..) in order to be able to manually correct the runaway trim.
Plane going nose down, push yoke forward at 500ft? I do not envy the crews at the pointy end of those flights. My heart breaks just thinking about it.
The Lion Air pilots must have been pulling back on the sticks until their tendons break, to no effect. I hope there is a special place in hell for Boeing execs.
[1] 737 Flight Crew Training Manual, chapter Non-Normal Operations/Flight Controls, sub heading Manual Stabilizer trim:
"Excessive air loads on the stabilizer may require effort by both pilots to correct mis-trim. In extreme cases it may be necessary to aerodynamically relieve the air loads to allow manual trimming. Accelerate or decelerate towards the in-trim speed while attempting to trim manually."
This was recently brought to the attention of members of a certain pilots forum that does not welcome lurkers, hence not adding a link.
Maybe not quite 5-year-old, but here's my attempt:
The elevator is the little wing at the back of an aircraft that tilts up and down to make the nose go up and down. When the pilot is flying, this up-down is what moving the yoke forward/back does.
The elevator also has a tab (the trim tab) part of the wing that can move independently from the main part. This trimming movement allows for adjustments to the plane's up/down movement that don't require the yoke forward/back (this is useful to "lock in" the current desired climb/descent/level flight so that pilots don't have to be constantly pushing/pulling on the yoke to get the plane to be climbing/descending/level the way they want it).
The 737-MAX has a system that automatically uses this trim tab to pitch the nose of the plane down when it senses certain conditions, without notifying the pilots. In this case (plane inexplicably pitching down), the natural response from a pilot is going to be to pull back on the yoke to counteract.
This can cause issues because the act of pulling back on the yoke increases the pressure on the elevator (because physics - the more the elevator deflects in an attempt to change the plane's attitude, the more force the airstream flowing over it exerts. This "catching the airflow" is why it can change the plane's attitude at all). Apparently on this plane if the trim tab is way out of line even if disconnect the erroneous system that was automatically adjusting the trim tab and try to reset the trim to a safe position by hand, the airflow over the "loaded" elevator (which is trying to counteract the position of the trim tab and keep the plane from crashing) is too strong to physically allow the manual control to move the tab. So the "correct" procedure is to push the yoke in (allowing the nose to go down/lose altitude) to reduce the airflow that's hitting the elevator, while frantically spinning the manual trip wheel to get it back to neutral. Then, once you've reset the trim manually, you presumably pull back on the yoke to get the nose up and pull the plane out of the dive.
The issue with that is that the ground can get in the way in between when you've let off the yoke and you've spun the wheel enough to get the trim tab back to neutral.
I wanted to update my explanation ^ a little bit - it's based on how trim works in smaller trainer aircraft (which are all I've flown). On a 737 there isn't a "trim tab" - instead the whole littler wing at the back of the airplane (tailplane) can change its position based on the trim, while the elevator is the adjustable tab at the back of that which moves based on the pilot's inputs.
I think the basic procedure for how to undo the excessive trim based on too much force to move the tailplane still is accurate though...
Incorrect, this describes a typical General Aviation aircraft with trim tabs. Most (all?) airliners use a trimmable tailplane, meaning the entire tailplane tilts up and down to trim for a specific speed.
Incorrect, this describes a typical General Aviation aircraft with trim tabs. Most (all?) airliners use a trimmable tailplane, meaning the entire tailplane tilts up and down to trim for a specific speed.
The only airliner I can think of that uses trim tabs is the DC-9 and its derivatives (MD-80/MD-90/Boeing 717). Some, like the L-1011, went in the completely opposite direction and use an "all moving tailplane" where the functions of the elevator and stabilizer were integrated into one piece.
An example fully trimmable tailplane in a general aviation airplane is the Mooney, at least the 201 and related models. Look at pictures of it and compare it to, say, a Cessna 310’s plane. You will see the “trim tabs” at the back of the 310’s elevator and none on the Mooney 201.
I seem to recall some tail draggers I flew had no trim tabs too.
Yeah this explanation is completely backwards. The "trim" moves the entire horizontal stabilizer. The elevator control moves the elevator (a moveable section of the back of the horizontal stabilizer).
In an average case (trained pilot, solid amount of experience, etc.) what is the turn around time between detecting this problem and fixing it in the air?
Like, how long does it take to determine the exact problem, spin the manual trim wheel to get to the point where you can recover from a nose dive in this case?
How does that number (in seconds I'm guessing?) translate to altitude levels?
By regulation, when a system fails (as designed) the pilot MUST be able to recover:
- in 3 seconds when in cruise
- in 1 second when on approach
- when in the landing phase - immediately!
Such a system would be certifiable.
Most modern airliners have ~10 "memory items" that are procedures that are to be recalled and applied immediately without consulting any checklists. Runaway stabilizer is such a memory item. But first you need to recognize the issue as such..
It bears to mention that the 737 is riding on it's "grandfathered" certification status from the 60's, getting a free pass on many newer requirements that are subjected to airliners designed today. This is why it doubly makes sense for the bean counters to not design a new aircraft.
That's really impressive turn around times. I wish I could debug most software errors in 3 seconds or less.
That is pretty frightening about the grandfathered rules.
I don't know much about cars but I do know they have a similar thing. Suddenly because you have a car 1 year before a point in time it can be obnoxiously loud but today it wouldn't be street legal. I almost can't believe the same thing happens with planes.
The situation is actually worse with airplanes. When automobile regulations change, owners can generally continue to drive older vehicles but manufacturers can't continue to sell new vehicles approved under old rules. But with aircraft, once a type certificate is issued the manufacturer can generally continue producing it forever.
I think (please correct me if I’m wrong), the plane’s “type” is fixed, and pilots have certifications for that “type”. So theoretically the plane is simialar enough to not require completely new training if a pilot is certified to the type - this new 737 Max is grandfathered into the 737 “type”. If it were different enough, then it would be a new type. If the plane is a new type, pilots, and likely all sorts of other things, mist be retrained, and reissued.
So there’s an incentive to not just make the type backwards compatible to keep the common “type”, but also not introduce too many new features that might bring into question the grandfathered training.
This 737 Max added this new “safety feature” without telling the pilots (because it’s the “same type”). And that feature seems to have an unfortunate interaction with other systems in some circumstances.
I don’t know the specifics, but I assume the process to get changes approved to an already-certified type of aircraft (the 737 family in this case) is less rigorous than what you’d have to go through to get an entirely new type certificate.
1. The confuser commands a nose down trim, this means that the leading edge of the tailplane is raised. In actuality, this represents a decreased angle of attack (think of tailplane as a upside-down wing).
2. Pilots haul back with all their might. This means that the elevators (the trailing control surfaces at the trailing end of the tailplane) deflect upwards in order to increase the angle of attack and create more "downforce" from the tail, raising the nose.
3. Think of the trimmable tailplane [1] as moving around a pivot. In reality it is a jackscrew/hinge combination.
4. The elevator deflections (the intuitive response) "creates a twisting force" the tailplane around the "pivot point" and against the desired direction that you want the trim to travel.
5. Unload the elevator pressure to make it easier to trim it. The key is that elevator deflections, despite intuitive are not sufficient. Luckily, it is a trained manoeuvre.
The elevator (smaller wing on the back) points up or down, pushing the air up or down, which in turn raises or lowers the tail/nose of the plane (it's pitch).
Some planes have little cutouts on the back of the elevator that move, thus deflecting the wind. Other planes, the whole back wing moves (stabilator).
To keep the nose pointed up or down, it can get tiring to constantly apply force on the pitch control. So now we can "trim", which changes the neutral position of the elevator to be higher/lower.
Some planes have little cutouts on the elevator or stabilator for trim. Other planes, the whole elevator / stabilator moves for trim.
Some times, when the whole elevator / stabilator moves up/down for trim, you need a lot of force to move it back down/up, especially if its neutral position has changed.
Occasionally, under high loads due to wind/pressure, you just can't. So you have to go to it's current neutral position (no matter how high or low) so you're not fighting a loosing battle. Then you have to reverse the trim. Then you can apply the opposite force.
You are correct in it being counter-intuitive and seemingly opposing the desired outcome. You need to recognize the situation fast and know precisely what you are doing. Unenviable position to be in at 500ft AGL.
In this case you are either going into a commanded descent into terrain or the broken computer will do it for you, at that altitude there aren't many chances of getting out of that situation in one piece.
From the previous yo-yo recording and now, a structural engineering boundary seems very likely broken at the connection area to elevator motor. Caused by swelling of a screw type plausible, or a punctured surface mounting causing a built up existence of a opposite hold in sudden decent, then lumbering heat.
Cars have power steering, where it's pretty much impossible for steering to require superhuman effort. Why can't the hydraulic assist of a plane be designed the same way?
Elevator upwards deflection loads the tailplane aerodynamically in such a way that it becomes harder to trim the tailplane in the required direction.
so I'm not sure what you mean by "matter of aerodynamics", because that comment suggests that it only gets harder due to the forces exerted by the air on the control surfaces, and so could be overcome by applying more force --- which a hydraulic system could be engineered to do.
The 737 stabilizer trim is actuated by steel cables running from the nose of the aircraft to the tail, guided by pulleys [1]. The same cables also make the wheels spin when the stab trim motors are running.
Most airliners with jackscrew activated horizontal stabilizers don’t have enough elevator authority to counter a fully deflected tailplane. I don’t think that’s in any way abnormal to the -Max. What is abnormal is the failure mode that seems like it can deflect to full nose down from stability augmentation.
There's a good article, Do you really understand how your trim works?, that explains how trim works, and in particular how stabiliser trim (what the author calls "trimming tailplane") differs from the trim tab ("conventional trimming") found in smaller planes (that many pilots train with). They operate pretty much the same to first order (for small perturbations), but quite differently for larger deviations from neutral. Bottom line, as you said: You can't overcome bad trim in an airliner by "pulling harder".
Even if this is true (which I suspect it's not, I think being able to override trim in all positions is a certification requirement, but I could be wrong), disabling the trim just disables automatic trim. It's still possible for the pilots to manually move the trim wheel to trim back up.
The 737 can definitely be flown into a situation where the elevator doesn't have authority to overcome the stabilizer. That's been true at least since the 737 Classic. Take a look at the Bournemouth incident.
Ah, interesting. That's nose-up, which is the opposite direction of what we're talking here, and seems to indicate that it is the combination of max thrust at low airspeed and large nose-up trim that exceeds the elevator authority.
It's not immediately clear, at least from my skimming of the report, whether a similar situation exists for nose-down trim, since in that case thrust will help the elevator with pitching up.
The current "industry standard" is 1 accident per 10 million flights. I think the MAX 8 has racked up something around 150K flights with 2 accidents. So yes, the statistics represent an anomaly.
I assume you meant: If an airplane is as safe as average then it has PUT_NUMBER chance of having 2 incidents after 150k flights. 0.01% is actually the number I'm getting, assuming parent estimates are correct and making naive assumptions. In other words only 1 every 10 000 airplane models will have 2 incidents that early on if they are of average safety.
That is different then stating the probability of it being as safe as the average airplane, which you can't do as easily without additional modelling/priors and bayesian statistics.
Lies, damn lies, and statistics.
The NH is that a plane has 1/10 [M * flights] failure rate. The odds of 2 failures in 20M flights falling in same (random) stride of 150K flights are 150K/20M = 0.75%.
[E: fixed numbers]
[EE: yes, I admit this calculation is incorrect]
If we assume that accidents are rare and independent per mile, then the correct distribution is a Poisson distribution with a parameter of 150,000/10,000,000 = 0.015. In which case the odds of no accident should be 98.5111939603...% and the odds of one accident should be 1.47766790940...%. The odds of 2 or more accidents is 100% minus those, which is 0.0111381302891...%.
It gets even worse when you consider the fact that both crashes happened while the plane was in the air. Nearly half of all accidents happen at takeoff and landing. This makes the per mile, just flying along failures even less likely.
Is that figure per model or per actual airplane? If the latter, 0.01% seems close to something I'd expect to actually see just by chance.
If I understand correctly, that's the probability for 2 crashes within any span of 150 kiloflights. I'm curious if it makes sense to ask about the first span of 150.
It's likelihood per 150k flights per model (although likelihood per 150k flights per individual plane would give the same answer, it's just a weirder question).
The assumption is that for the average plane all accidents happen independently from one another. Under such an assumption, the probability for any span of 150k flights is exactly the same as the probability for the first span of 150k. So it would not change the answer.
If you roll a die a 1000 times, the odds of landing on a 6 on roll 999 is the same as it landing on a 6 the very first roll.
How did you get that number? Assuming a binomial distribution with p=1/10^7 and n=150*10^3 samples as the null model, the probability of 2 or more accidents happening by chance is 0.011%.
On Mar 13th 2019 the FAA announced shortly after the President had signed the executive order, that they were probibiting Boeing 737 MAX aircraft to operate in US airspace and stated: "On March 13, 2019, the investigation of the ET302 crash developed new information from the wreckage concerning the aircraft’s configuration just after takeoff that, taken together with newly refined data from satellite-based tracking of the aircraft’s flight path, indicates some similarities between the ET302 and JT610 accidents that warrant further investigation of the possibility of a shared cause for the two incidents that needs to be better understood and addressed. Accordingly, the Acting Administrator is ordering all Boeing 737 MAX airplanes to be grounded pending further investigation.”
I have to admit that after reading the tweet and thinking about the gravity of what happened, of the horrible end the innocent passengers went through, I choked up... It's just unimaginable.
I hope they find out the cause & make sure it never happens again.
> In a statement, Boeing said it recommended to the Federal Aviation Administration that the 737 Max be grounded "out of an abundance of caution and in order to reassure the flying public of the aircraft's safety."
A company is recommending to their regulator that the regulator take action against them. That is a pretty solid indicator that the lawyers have a rough idea of potential liability and are now trying to mitigate damages.
> Early Tuesday, Dennis A. Muilenburg, the chief executive of Boeing, spoke to President Trump on the phone and made the case that the 737 Max planes should not be grounded in the United States, according to two people briefed on the conversation.
I was merely commenting on the rationale and strategy behind their decision as someone who has been in a similar position. Though in my case only bank accounts, not lives, were at risk.
And for the record, I made the same call. It's not easy but I'm certainly not judging Boeing for weighing their options and moving forward with a strategy that gives the company the best chance at recovering from this mess.
Why “against?” Surely Boeing is on the same team as everyone in wanting prevent any further loss of life. If they believe there is a safety issue I’m sure they would encourage the FAA to take action so airlines were obliged to.
When Boeing sells or leases the planes to the airlines there is almost certainly a clause in the agreement that represents & the warrants the plane is suitable for it's intended use: flying. An FAA declaration grounding the planes quite clearly means the planes aren't suitable to fly and Boeing will be on the hook to compensate the airlines for the costs associated with the groundings. We're talking millions of dollars a day.
They also have thousands of outstanding orders for this model plane that are, at best significantly delayed and perhaps in jeopardy.
What's the current status regarding analysis of the black box data recorder? The only source I've seen [0] states that Germany lacks the software to analyze it. "This is a new type of aircraft with a new black box, with new software. We can't do it," BFU spokesman Germout Freitag said.
This shouldn't be Trump announcing the ban. Either FAA or Secretary of Transportation should be announcing the grounding of flights. Its just odd to me that Trump would be involved...
The President is analogous to the Chairman/CEO of [most of] the executive branch. That role can tell them what to do and what do focus on, but mostly doesn't. He told them what to do, now the FAA has to do it. The Secretary of Transportation could likely have unilaterally issued an order without needing it to tell the FAA what to do, or waiting for the President.
But either way, this is symbolic and shows the stance of the government to the world and internally. The highest office in the US is grounding the planes like the rest of the world is, the administrative nuances are irrelevant. Boeing and the airlines would be the ones to challenge it, way to go for PR.
A country isn’t a company, nor is the executive branch. Agencies operate somewhat independently, precisely to prevent the appearance (and reality) of political interference. In practice, this means the president does not have the power to make agency decisions. For some agencies, he might get to fire the director. But even then, he would have to fire everyone down the line to the individual or group making the decision.
Violating that tradition is rather stupid for a President. Not only are FAA decisions now tainted, he is putting himself square at the center of blame for anything negative happening from now on. It’s even worse considering there aren’t really any symmetrical opportunities to shine with a job well done in aviation safety comparable to a crash.
> A country isn’t a company, nor is the executive branch.
It is an analogy, which is why I used the word analogous, and it still fits.
The power of the Executive Branch is vested in the President of the United States, who also acts as head of state and Commander-in-Chief of the armed forces. There isn't any framework to have a rebuttal to that, this is as succinct as it gets.
SOME agencies are independent of this structure. They are called independent agencies.
Other agencies are not.
The President's primary role in this capacity is to steer the executive branch, and this is done using rather mundane executive orders which are usually merely plans, again ANALOGOUS to a companies quarterly or annual goals. A CEO lays out the mission and the organization follows that.
The job title is a 3-part job. Head of executive branch, head of state, and commander-in-chief of armed forces. The celebrity status and reliance on The President's every move and stance on everything is merely happenstance, but a byproduct of the constitutional government becoming involved in every aspect of American society, having subsequently created all these "not-companies" with millions of employees, and perpetual armed conflicts around the world.
So finally, head of the executive branch, for agencies not independent of this structure, the President is ANALOGOUS to the Chairman/CEO and has ultimate say in steering them. There is no tradition that was violated.
Anyway, on the topic at hand, the FAA followed the order and indications from the President and issued their own.
Fortunately there are laws against him being a "CEO". The "spoils system" he has sought to restore permitting him to fire those who disagree with him politically and place those he favors in their place are blocked by a series of progressively increasing laws culminating in the 1978 Ethics in Government Act which limits his ability to engage in CEO-like acts of political influence over the civil service.
His ability to directly influence, and damage, the executive branch's operation in service to the people to what he wants is thus limited.
> Fortunately there are laws against him being a "CEO"
Do you know what the Presidency is? It's the head of the executive branch. By definition, Chief Executive of the United States. The law specifically are for the President being CEO -- that's exactly what being president is. The one who signs bills, runs the organizations who enforce the laws, and runs the military that defends the country. The president is 100% in charge of the Executive Branch and all of its agencies -- that's exactly what the job is! He could fire every head of every non-independent executive agency tomorrow and it would be 100% constitutional.
That is...unclear, at best. The only account of the decision making I've seen in any news source that comes from anyone involved (e.g., excluding CNBCs unsourced claim of an "executive order") is Boeing's claim that they recommended the action "in an abundance of caution" to the FAA which acted on it. (EDIT: Actually, the FAA has just tweeted that they made the decision, based on evolving evidence from the investigations, so that's another narrative.)
Of course, the White House can assume the privilege of announcing any decision from anywhere in the executive branch, and the President announcing it as an "emergency order" that "we" are issuing is factually correct where "we" refers to the Executive Branch.
Of course the President can just tell the FAA what to do. I understand that.
The question is how the public should have been informed by the event. Dan Elwell, the acting director of the FAA, is both a military and commercial pilot. If he made the announcement, it would have carried far more weight than Trump (who likely doesn't know much about airplanes).
That seems to be a closer fit to the kind of industry ties he has had then either Pai or DeVos. Pai's industry ties was as a lawyer for Verizon, whereas Wheeler's were as head of first the cable trade association and later the wireless trade association, and having been involved in several telecom companies. That seems a much closer match to Elwell, who was VP of a major aerospace trade association and a pilot and an airline executive.
Obama's last FAA director wasn't even a pilot. He had a degree in political science. At least Elwell has actually flown airplanes -- including 16 years flying airliners for American. He also has combat aviation experience. Elwell is far more competent than Michael Heurta. Huerta's background was in politics, working for New York City and Later the Port of San Francisco. No flight experience, no airline experience, no general aviation experience.
People criticized Trump for putting a non-scientist at the head of the Department of Energy, however, where is the criticism of Obama for putting a non-pilot as the head of the FAA? When Trump does something wrong, sure, criticize him, but Elwell is an experienced, relevant choice to head the FAA -- especially compared to Huerta. Reducing Elwell to "Lobbyist" is silly, if one actually looks at his background.
That would have only carried weight for those who know who Dan Elwell is. He carries no weight with me other than apparently being "acting director of the FAA". The president, even if he's disliked by many, carries much more weight for the average person.
The public don't need to know who Dan Elwell is, they need to know that the decision to take a very disruptive emergency safety precaution has been taken by the relevant safety body after evaluating the currently-known relevant information. (The people who actually execute the grounding of the Max know who he is anyway)
I don't actually think Trump is doing anything wrong in trying to take responsibility for the action, and suspect the decision was reached through appropriate channels rather than by him reading something by a pilot on Twitter, but having a president known for more being capricious than his understanding of aviation safety as the figurehead behind the decision does make it look less like a reasoned decision to the average person, especially if they have strong anti-Trump priors.
There is no question that the acting director of the FAA would be more knowledgeable about airplanes than Trump. While technical individuals are needed during the investigation, I don't believe that this decision warrants a full-on root cause analysis prior to making the decision to ground the planes. The FAA's Primary Mission is to ensure the safety of civil aviation, and from a safety stance, if the acting director is incorrect, and another plane was to go down, hundreds of people would likely be killed.
I predicted two days ago that this would turn into a shit storm of hysteria, justified or not. The President exerting his authority is similar in that sometimes these events turn too emotional and fearful. He made the right call for that sake.
I mean, he has a phone-line, and his Secretary of Transportation is in charge of the FAA. So its just odd that he'd personally involve himself in this issue. There's a myriad of ways for Trump to get this done with better optics.
Even if Trump were to give a phone call along the lines of 'Ground the Plane or else I'll write an executive order' , the optics of the situation would be so much better if Chao (Secretary of Transportation) or Dan Elwell (FAA Acting Administrator) were to give the announcement instead.
> if Trump were to give a phone call along the lines of 'Ground the Plane or else I'll write an executive order' , the optics of the situation would be so much better
If the President is requiring it then the proper mechanism to do that is an order.
You're suggesting a side-channel phone call and a threat so that he's still deciding but it's recorded as someone else's decision for PR purposes, and you think that's better? That's a terrible idea.
> You're suggesting a side-channel phone call and a threat so that he's still deciding but it's recorded as someone else's decision for PR purposes, and you think that's better? That's a terrible idea.
I disagree with GP, but this is basically how firings are handled at high levels.
It's very rare for a POTUS or a corporate CEO to actually fire a direct report. Instead, they say "you have X days to resign before I fire you" via a side channel, and most of the time the report opts for the resignation.
(funny thing is, at the first company I worked for, the CEO did this to the VP of Engineering... and the VP assumed he was bluffing, waited out the whole 30-day period he was given without resigning, and then got walked out of the building one morning in front of everyone who was there that early... and the guy who was in charge of walking him out was one of the people who was promoted to replace him)
Remember that Trump knows a lot about planes. Unlike most people here he owns a big plane made by Boeing. As well as being a narcissist this is something he can feel he can understand, it's his topic, he pays the bills to get his own plane serviced.
more to the point, who told the FAA bods not to pull the plane? Was this the President too?
Because of how this has been handled by the Trump I think Boeing now have a 'Samsung Note 7' on their hands, i.e. a product that isn't going to be re-released as it is poorly engineered and can't be fixed by just changing a supplier or two. It was a hack with another hack to keep the hack okay. There will be a who knew what and when scandal. This won't be like the Dreamliner teething issues due to two lost planes. People can forgive teething issues but a scandal is a different beast.
Owning a plane does not equate to understanding anything about them, easily proved by his completely stupid tweets about the complexity of modern aircraft being a bad thing.
> In August 1989, a Trump Shuttle flight arriving in Boston incurred a nose gear failure upon landing due to maintenance errors by Eastern personnel prior to the acquisition. Trump personally flew on the next Trump Shuttle flight to Boston in order to manage the media reaction to the incident.[3]
> his Secretary of Transportation is in charge of the FAA
I actually don't believe this is true - I can look up citations in a bit, but the FAA is an independent body whose directors are appointed by the president.
> but the FAA is an independent body whose directors are appointed by the president.
The Federal Aviation Agency was an independent agency, but the Federal Aviation Administration, which it became, is a subordinate agency within the Department of Transportation. It has an Administrator, but it does not have directors, commissioners, or some other multimember voting governing body.
An EO is the legal mechanism to command an agency to take an action. Agencies shouldn’t be taking instructions from random tweets, TV appearances and speeches as it’s hard to interpret the exact meaning. Further if some random bureaucrat were to act on a random Tweet and then be sued they’d be unable to say “I was just following orders.”
> An EO is the legal mechanism to command an agency to take an action. Agencies shouldn’t be taking instructions from random tweets, TV appearances and speeches as it’s hard to interpret the exact meaning.
Yes, but it'd not be unusual for the agency's director to check in with the president on a course of action or vice versa, verbally or via memorandum, without the president formally invoking his presidential authority via executive order.
To put the whole thing in perspective, the number of EOs issued annually by recent presidents Bush and Obama was very modest, averaging 36.4 and 34.6 respectively.
> It sounds like he had to go to an Executive Order to get the FAA to comply.
The words he used was "emergency order" and "we", not "executive order" and "I". CNBC is reporting it (not quoting any official source which says that, and citing only the President's "emergency order" public statement) as an "executive order", but other news sources are not, and Boeing is saying that they recommended the grounding to the FAA.
My initial impression is that this is an FAA action based on Boeing's recommendation that the White House wanted to take the press attention for.
> My initial impression is that this is an FAA action based on Boeing's recommendation that the White House wanted to take the press attention for.
That would make me feel better if this were true. It seems to match my expectations for who is in charge of various decisions, as well as the politics that Trump likes to play. So it makes sense at least.
To me another plausible explanation is that the reason the FAA _wasn't_ grounding them was because Trump said not to.
> Early Tuesday, Dennis A. Muilenburg, the chief executive of Boeing, spoke to President Trump on the phone and made the case that the 737 Max planes should not be grounded in the United States, according to two people briefed on the conversation.
Maybe Boeing changed it's mind in between yesterday and today?Or that reporting was inaccurate?
Or, that's exactly what happened, but then today either Trump or Boeing or both of them realized this wasn't gonna fly (no pun intended), and that they had to be grounded, they talked to each other again, Trump decided he wanted to make an announcement about it because he likes being on TV about whatever he's thinking about at the moment. (I'm not sure an "emergency order", which Trump said it was, is even a thing?)
I mean, really, who the fuck knows. This administration doesn't tend to make a lot of sense, and it's kind of kremlinology trying to guess why they do what they do.
Maybe he was letting FAA to do their job to avoid the appearance of interfering, but the external pressure was getting too high and FAA was dragging their feet so he stepped in to overrule. Interesting to see who's the original appointter of the FAA commissioners.
First of all, there is a backlog of higher priority nominees. It wouldn't be good to distract congress from those.
Second of all, the constant harassment of this administration must be having a huge impact. A person has to be slightly crazy to accept a nomination. They and their family will be facing physical danger, legal danger, and more. Lots of competent people are thus unavailable as choices. The constant harassment has had a real negative effect on the quality of our government.
I think you have cause and effect reversed there. The candidates aren’t low quality because they face difficulty. The administration’s candidates face difficulty because they’re low quality.
Even if you are right about them being low quality (a disputed political opinion) it should be obvious that no 100% sane person would put their family at risk by taking one of these jobs. Good people are thus eliminated from consideration. Those who feel that the choices would be low quality are thus forcing the choices to be lower quality.
Put yourself in their shoes. You have a normal family and could earn millions of dollars per years in a nice comfortable corporate executive position. How insane do you have to be in order to take something like $150,000 while living in the expensive DC area and being unable to simply go out to eat in public? What normal parent would subject their kids to the abuse?
Scaring away qualified people does not improve the government. You don't do that unless seeing Trump do badly is so important to you that you are willing to sacrifice the wellbeing of the country itself.
This is by far the most interesting aspect of this story. I expected that the US would ground these planes soon. There was too much pressure to follow the rest of the world. But having the order come from the President rather than the FAA is highly unusual. Seems like something very strange must be going on behind the scenes. Maybe the FAA is reluctant and he’s forcing their hand, or maybe he’s trying to take credit for their decision.
Does anyone have any idea WHY the US was the holdout here? I'm not well-versed, but my understanding is that aviation safety is generally very good, and that the US is not an outlier on the bad side. While grounding a plane at this point is premature from the stance of conclusion, it seems reasonable from the standpoint of excessive caution that seems to be the norm for the industry.
I can conjecture about Boeing being a big US manufacturer, etc, but is there any evidence at all for why the US held out on this one? My initial reaction was that there must be a good reason for the holdout, given our safety record, but on reading more about it, I've not seen one. (Again, relative to the stance of excessive caution).
For the sake of argument: their historical reputation allowed them to make determinations of safety independent of political considerations that other aviation authorities must make.
While it certainly sounds like there is a flaw in how the system handles erroneous sensor data, or that the interface promotes incorrect actions, the independent groundings of 737 MAX 8 planes probably are not independent in sense of each authority coming to its own determination based on their professional opinions alone. It would be politically foolish to be the lone holdout in your region.
There is a real cost to grounding these aircraft, and I'd imagine that if they are grounded without specific questions that need to be answered or problems that can be fixed, it becomes even more difficult to un-ground them later.
"Regular FAA oversight of an ODA is accomplished by a team of FAA engineers and inspectors to ensure the ODA holder functions properly and that any approvals or certificates issued meet FAA safety standards."
I don't know about the specific concerns in that video, just replying to the insinuation that Boeing has some strange deal that exempts their planes from oversight by the FAA. They don't.
While there might be issues of regulatory capture (ie too much influence of the regulatee (<- not a word, but it should be...) on the regulator)), my personal opinion is that there were two consistent courses of action:
1. Ground the MAX after the reasons for the Lion Air crash had became clear, as it's not airworthy.
2. Do not ground the MAX, as it's sufficiently airworthy.
This new crash had not provided enough information initially to conclude otherwise.
However, the FAA is sort of arguing that there is now enough new information from the second crash to support the decision to ground it.
This is the answer. The FAA considered the Max 8 after the Lion Air crash and determined that it was safe to fly, even taking into account the cause of the Lion Air crash.
If that was determination was done correctly, then there is no reason to ground every plane of that model, just because another one crashes shortly thereafter.
The FAA obviously is inclined to believe that they did that determination correctly. Of course, they could be wrong.
It will be very interesting to see how the Ethiopian investigation turns out. If the cause was the same as Lion Air, then the FAA will come under tremendous pressure to reconsider what constitutes "safe to fly".
(IMO the industry in general will come under hard questioning about the role of software in compensating for aerodynamic issues. Yeah the military does it, but we have different standards for airlines.)
But if it turns out that some other factor caused the crash, unrelated to the Lion Air cause, then the FAA will come off looking insensitive but ultimately justified in their determination.
4. The issue was pilot operation of the aircraft. Apparently it was possible to disable the old 737 autopilot with stick input despite that not being the method prescribed by the procedures. MAX didn't involve simulator training, so a less disciplined crew in MAX might not correctly disable autopilot in an emergency despite the procedures for doing so still being correct.
This is incorrect. The MCAS doesn't even get triggered when autopilot is on. And surely when a system malfunctions, the issue is not entirely pilot operation.
Terminology issue in the parent: I believe the correct statement would be that in the non-MAX 737, extreme stick movement would countermand auto-trim. In the MAX, this is not the case (at least when MCAS is the bit making adjustments). It was an "undocumented feature" that (less experienced?) pilots were relying on.
I don't know, but I wonder whether they were expecting to have preliminary findings within a few days that would clarify the choice. I gather that it's a more disruptive move for the US than for many of the countries that grounded the plane sooner because the US fleet may be larger.
Is the count not also significant? I don't know enough about the industry to know.
I mentioned it because when I first heard that there were so many other regulatory bodies grounding the fleet, I was surprised about the FAA. When it was pointed out that many of those regulatory bodies represent countries having a handful of these planes to begin with, I was still surprised, but it made a little more sense that the FAA might have more to lose if the decision proved rash.
Regulators come and go. The person holding the reigns at even given point in time is potentially not as good or unbiased as the predecessors.
From what I've read so far, there's absolutely no clear indication at this point it was solely pilot error, and common sense dictates you ground the planes before more crashes happen.
I believe that the FAA has a strong tradition of acting on evidence, not presumption. It's the flight certification equivalent of "innocent until proven guilty" (although they usually operate at a much lower level of proof than a court of law.)
I don't usually make libertarian-style arguments, but until there's evidence pointing to a specific safety of flight issue from the latest crash there's no justification for the government effectively "taking" airplane owners property by preventing its use.
At the moment there is specific evidence, I have no doubt the FAA will act swiftly.
> effectively "taking" airplane owners property by preventing its use.
...its use for transporting OTHER people/stuff in air over OTHER people's property (and lives). I'd be surprised if the FAA licenses didn't have clauses that basically allowed explicitly this.
Regardless, I don't find your arguments persuasive. The FAA didn't wait for "evidence" before banning cellphones, e-readers, etc on flights; they've grounded planes before investigations were complete before...which was why I asked my initial question: What was different this time.
I agree that the definition of "evidence" they use isn't obvious, and I'm not at all familiar with where the rules for cabin electronics come from.
I'm not saying they can't do it, they obviously can (and just did.) All I'm saying is that there has to be some evidence that the crash is for a reason that implies other aircraft are affected. And obviously the standard for transport category aircraft is higher than for smaller airplanes. But it can't just be "we gotta be sure", because then you can't let anything fly at any time.
Imagine if every time someone had an accident in the same model car you own, the DOT prohibited that model car on the roads "out of an abundance of caution" until it was proven that it was not a design fault in the car. While there arguably would be an improvement in safety, it would also be incredibly disruptive.
What standard of risk would you apply? Because you have to draw the line somewhere.
Separate question - and your arguments are all logical. My question was "given the standard of risk that HAS been applied, why was this time different?"
The safety record of car travel in the US is dramatically different than the safety record in air travel.
If an airplane crashes because it's hit by a missile, or because there's a bomb aboard, or because a suicidal pilot flies it into a mountain, that is no reason to ground it.
Thus, more evidence is required to ground an airplane (that has, after all, gone through the certification process), than two crashes.
I agree with the assessment that the MAX has a problem; I'm saying "oh, two crashes" by itself is not sufficient evidence for that conclusion.
As someone pointed out in this thread, there were three B767 hull losses between September and November 2001, but two of those were caused by 9/11 terrorists and don't tell you much about the airworthiness of the aircraft.
FWIW, IMHO it's not pedantry, it's precisely the core of the discussion. The 737 MAX was deemed airworthy during certification, and deemed airworthy after Lion Air, and a further crash by itself does not change that. It is only the details and circumstances of the second crash that can provide evidence to challenge the conclusion of airworthiness. Just reflexively saying "crash, ground it all" is mistaken.
The point I'm trying to make all along is that it is precisely "those details and circumstances of the second crash" (that have emerged over the last few days) that make it so worrisome and warrant a grounding. It is not the fact of a second crash by itself.
The fundamental question is this: should the plane have been grounded immediately after the second crash? Many here seem to think that yes, obviously. I think that no, one unexplained crash of a certified plane does not warrant grounding. Once details and circumstances emerge that are indicative of some fundamental design flaw, or multiple unexplained crashes (as with the comet), of course ground it.
Is that a substantive disagreement, or "pedantry"?
When the second crash occurred, that was then TWO unexplained 100% fatal crashes within 5 months, with extremely similar circumstances and evidence pointing to the same root cause. Basically, the first crash with lion air had them on red alert for this model of plane. The second crash was nearly identical and was all they needed to ground them instantly.
On 24 March 2015, Germanwings Flight 9525, using an Airbus A320, flying from Barcelona to Düsseldorf crashed near Digne in the Southern French Alps, killing all 150 on board. They didn't know it was a suicide pilot until after they investigated. Yet, A320s kept flying in the meantime.
On 29 March 2015, Air Canada Flight 624, using an Airbus A320, flying from Toronto to Halifax carrying 138 people crash landed short of the runway. The aircraft was badly damaged and 23 people were injured.
On 14 April 2015, Asiana Airlines Flight 162, an Airbus A320 with 82 people on board, lost height on final approach to Hiroshima Airport in Mihara, Japan, struck an antenna, and skidded onto the runway on its tail, spinning 180 degrees before coming to a stop. Its main landing gear collapsed and the aircraft suffered damage to its left wing and left engine. 27 of the 82 people on board were injured.
Three incidents, on respectable, high-safety airlines within 3 weeks of each other all with the Airbus A320. Yet, those planes weren't grounded, not even for five minutes. Three serious incidents within 3 weeks of each other is "empirical evidence" that the A320 is unsafe.
But we have a crash from Ethiopian Air, on a plane where the first officer had only 200 hours of total flight experience. And another crash months ago on Lion Air (a ridiculously unsafe airline) and that's "empirical evidence" that the airplane is bad?
Lion Air should be grounded. Ethiopia shouldn't be flying planes with student pilots in the right seat. There may be issues with the 8 Max, however, it's a fact that inexperienced pilots, bad maintenance, inferior safety processes and negligence will exacerbate any potential flaws in the aircraft. The fact is that in the case of Lion Air, if it were Southwest Airlines operating those flights in Indonesia, flight 610 never would have crashed. Lion Air had days of reported issues before the crash and they ignored them. Look at Lion Air's incidents and accidents: https://en.wikipedia.org/wiki/Lion_Air#Incidents_and_acciden... It seems that can't even taxi a 737 safety, let alone be trusted to fly one. And right now we're complaining about the FAA? We should be complaining about airlines that are being allowed to operate with this slipshod respect for safety.
The US, Canada and Europe hasn't had any 8 Max incidents -- the incidents happened in organizations that were operating in ways that would never be allowed in US, Canada, or Europe. That fact seems to be getting ignored in favor of complaining about the FAA or Boeing. The US flies a lot more 8 Maxes than Ethiopia or Lion Air, yet not a single crash. Is that just coincidence or does the US/Canada/Europe just do a better job?
Asiana Airlines Flight 162 was an Airbus A320-232, manufactured in 2007
Air Canada Flight 624 was an Airbus A320-211 manufactured in 1991
Germanwings Flight 9525 was an Airbus A320-211 manufactured in 1990.
The Asiana and Air Canada incidents were similar, but the aircraft were of different models, one was 7 year old and the other was 24 year old. The German Wings and the Air Canada aircraft were similar models, but both planes were 23-24 year old, and the incidents were completely different.
Compare that to the 737 MAX 8. Two fatal crashes, during the same stage of flight, with identical models, of similar age. 2 out of 350 planes crashed, where the fleet is barely one year old on average.
Also see @salawat above on nacelle lift-induced pitch instability. We now have airliners that begin to resemble the F-117 in their dependence on computers for controllability in flight.
There's nothing wrong with unstable airframes. Military craft have required computer assisted flight for decades.
What's problematic with 737 MAX is that the stability assist was obviously installed as an after thought, and even worse, it's dependent on instrumentation that does not have several layers of fault tolerance as would be the case if it was actually built with the care that planes actually require to be as dependable as they are.
So the instability is not a problem. That boeing tried to get around it with a cheap patch of jury rigged software that is depending on input from non-fault-safe instrumentation, is.
Sure, I'm not saying it's a good idea, just that I don't see any inherent problems with it - given that fly-by-wire systems have been used for decades I would consider them well understood.
IIRC, the instability is caused by the engine nacelles (the metal shroud around the turbofan), and therefore is present whether the engines are active or not.
That's a huge stretch. The fix was to work around a certification requirement that the control forces shouldn't decrease as the aircraft approaches the stall. This is a long way away from the aircraft being inherently unstable.
"Fehrm said Boeing must have added this system on the MAX because when the angle of attack is high this model is less stable compared to prior 737 variants. That’s because the MAX has bigger, heavier engines that are also cantilevered further forward on the wing to provide more ground clearance. That changes the center of gravity."
It seems like you think that contradicts what I said. The system by design adds a little trim in very specific circumstances. That's not the same as being needed because the aircraft is aerodynamically unstable. That is a term which has an actual definition.
That said there are airliners out there which are unstable in the longitudinal axis and require a yaw damper to prevent Dutch roll.
My intention was not to claim 737 MAX had the same aerodynamic nature as, say, F-16, but in the scope of the discussion point out that fixing instabilities with flight software can be made to work reliably.
The main argument was that it was inherently a bad idea to require computer assist to maintain stability and decades of military planes demonstrate that you can engineers such systems to be more or less fault safe.
Agreed. I think unfortunately most of the people outraged by this decision are completely unaware of the complexity of systems on board a modern airliner. There are other systems like the Mach trim system which adjust the trim in response to Mach speed. There are yaw dampers on aircraft with good reputations which are critical for safety of flight (e.g the concensus is the 757 will depart controlled flight without an operative yaw damper). Even on the 737 flying with an in-op yaw damper has been known to make light chop vomit inducing.
There was a sibling comment somewhere in this post that stated that airbus doesn't introduce a layer between the pilot and the aircraft. This couldn't be further from the truth (assuming normal control laws). Applying full back stick on an airbus will hold the aircraft right on the edge of a stall. Applying full left or right on the stick will neatly roll the aircraft to 60 degrees of bank. Releasing the stick at this point will roll the aircraft back to a perfect 30 banked turn in the same direction. This isn't normal behaviour by any stretch.
If anything I think Boeing are suffering from not going to fly by wire control earlier. That would have made this whole subsystem irrelevant. You'd just apply the desired behaviour in the response curves in the control software.
A combat aircraft can trade reliability for superiority, you increase one kind of risk to lower another. This trade-off simply does not exist in civilian aviation.
Why does that matter? There are plenty of natural things that are scary as hell, and plenty of unnatural things that aren't.
The reason you don't see it in nature is that macroscopic organisms never evolved a continuously rotating joint. It's a hard problem for evolution to solve; how would blood vessels cross that boundary?
But of course machines have no such constraints, and the wheel and axle is hardly a new (or scary) invention.
It does not. Once you go through one rotation you've ripped all the muscles and ligaments off, ripped all your skin, and can no longer rotate it any further. Oh, and your entire arm will die in short order because you've ripped all the blood vessels delivering it oxygen.
Is it possible we're talking about two different things? Making a circle with your arm isn't the same as rotating it, and just making a circle isn't particularly useful for flight or locomotion. Imagine attaching a wing to your arm and making a circle -- half the time isn't going to be attacking the wind the wrong way. This wouldn't work to, e.g., fly a helicopter. You need real rotation.
What? Of course there is somethig wrong with unstable airframes. This is not a figther jet where it may make sense to maximize maneuverability, it is a bloody airliner, where stability and reliability should have been the design goals.
I disagree that "instability is not a problem". In military aircraft that are unstable it's common for everyone in the plane to be in an ejector seat or to have a parachute. Can you provide statistics on how many (or what proportion of) military planes with inherent instabilities routinely carry passengers without parachutes?
It doesn't matter why they have them, the fact that they are there changes the overall risk equation for the aircraft. Many military planes have bailout procedures because everyone has ejection seats or parachutes. Civilian planes universally do not. What is an acceptable risk in one circumstance is not necessarily acceptable in another.
E.g. higher redundancy of HW & SW, stricter testing/checks/validation of flight envelopes, more feedback to the pilots about why a computer is performing certain actions, etc... than military aircrafts using the same systems.
> Many military planes have bailout procedures because everyone has ejection seats or parachutes.
Do any modern military non-fighter jets have bail out capabilities? It was my understanding that you couldn't even put on a parachute in flight to jump out. You either had an ejection seat, or no capability at all.
The B-1, B-2, and B-52 bombers all have ejection seats. Some other combat aircraft, like the AC-130, have bailout procedures and the crew usually all has parachutes. Almost all other planes are either fighter jets with ejection seats or transport aircraft which are substantially similar if not identical to civilian aircraft in terms of dynamical stability.
It does matter why they have them, if you're using their having them as evidence that something else is a problem.
Swap out "instability" for "drab paint jobs" and see:
> I disagree that "drab paint jobs are not a problem". In military aircraft that have drab paint jobs it's common for everyone in the plane to be in an ejector seat or to have a parachute. Can you provide statistics on how many (or what proportion of) military planes with inherent drab paint jobs routinely carry passengers without parachutes?
Yes we can make an argument incoherent by swapping words in and out.
In this case the argument is not that a is evidence of b, it is that a ameliorates b. And that the risk of b is therefore priced differently where a is also present. So where a is not present, we must price the risk differently.
How that assertion relates to the historical record may be of interest.
Risk is assessed on a case by case basis. When people ask "is the risk of this system acceptable given its mission role" the answer depends on all of the characteristics of the system. In the case of military aircraft that means that both the fact that the airframe may be dynamical unstable in flight and that every crew member has an ejection seat are taken into account. And whether or not the plane is expected to be used in a combat environment will play a huge role in the acceptable levels of risk as well.
To blithely say "oh well, military planes do X so X must be fine for civilian aviation as well" is either intellectually dishonest or fundamentally naive.
It strikes me as unlikely that the military is taking the attitude "it's OK if our planes fall out of the sky during normal operation, because we have ejection seats".
I meant using computer assist to maintaim stability in vehicles as such is well known and widely used feature. The problem is not the computer assist, the problem is that it was obviously implemented not rigorously enough and depends input from non-fault-tolerant sensors (since making it fault tolerant apparently means Boeing would have needed to do some expensive qualification work due to the changes to the sensors).
As I understand it, this effect is only noticeable at very high angles of attack, and is not present in normal flight regimes. (Which is why the MCAS system only activates near the stall.)
Having an unrecoverable stall mode is not a desirable flight characteristic, for sure, but I don't think it's unheard of. For sure it's nothing like inherently unstable airframes as used in fighter jets.
The effect I refer to as being unheard of in previous 737 hulls is the positive pitch instability. I don't want to repost the whole comment, because I think that's frowned upon, but someone did provide a link.
My rather limited understanding is that the airframe certification path Boeing used was one meant for fast-tracked recertification of minor configuration changes of the same hull. The main idea being that the manufacturer need only prove that the reconfiguration meets the same or similar flight characteristic requirements as the hull it was derived from.
This lets them produce/sell a technologically refreshed product without having to pass the rigorous testing normally associated with type-certifying a new airframe. The important characteristic of this is that the onus for this certification is left to the manufacturer. I do not know if the FAA actually independently confirms the recert is justified, or just plays it via honor system.
Old 737 hulls definitely didn't have this characteristic onstability, or do-or-die reliance on functioning AoA sensors, so while I agree there isn't anything wrong with incorporating instability into a design to satisfy some specifications per se, I'd still contend that the addition of that instability should disqualify an airframe from being recertified as a reconfiguration of an older one, and should require more extensive testing/training before pilot's are cut loose on it.
If anyone else has more accurate understanding of type certification, I'd be thrilled to learn the specifics.
Im pretty sure the problem is that a sensor failure is causing it to believe it is at a higher angle of attack than it actually is, but I'm only skimming.
Yes, that's the present problem. I'm referring to the inherent instability issue that was alluded to. The stick pusher / MCAS is designed to prevent the plane from getting into a state where it's unrecoverable.
IT wasn't inevitable. There's nothing that's found to be unsafe about the aircraft. If anything it shows that airlines in other countries don't train their pilots properly. MCAS can be disabled by an easily visible switch directly in the cockpit and you can override it with manual trim control as well. The Lion aircraft that crashed before was having MCAS problems _FOUR_ flights repeatedly before the one that crashed. Third world aircraft maintenance combined with poor pilot training and non-idiot proof software made these disasters happen. It's not something that would happen in the US or any other first world country.
American pilots made complaints about MCAS as well.
> [It is] unconscionable that a manufacturer, the FAA, and the airlines would have pilots flying an airplane without adequately training, or even providing available resources and sufficient documentation to understand the highly complex systems that differentiate this aircraft from prior models
> The Flight Manual is inadequate and almost criminally insufficient
But we hear your "third world" and "idiot" dog whistles loud and clear.
I’m sure you’re willing to hop on a flight with one of these planes, but I’m not and I doubt the majority of people who’ve heard about it are. Canada saw the same sort of flight pattern dip in the new crash that happened to the old one. It’s only that the FAA administrator is a lobbyist of the air manufacturing industry that they didn’t follow suit.
> Third world aircraft maintenance combined with poor pilot training and non-idiot proof software made these disasters happen. It's not something that would happen in the US or any other first world country.
We're nowhere near having gathered enough facts to put forward claims like that.
Boeing said no training was required to save on money. If that was the point of this 737 revision, it stands to believe that the airlines would believe them.
"On March 13, 2019, the investigation of ET302 crash developed new information from the wreckage concerning the aircraft's configuration just after takeoff that, taken together with new ly refined data from satellite-based tracking of the aircraft's flight path, indicates some similarities between the ET302 and JT610 accidents that warrant further investigation of the possibility of a shared cause for the two incidents that needs to be better understood and addressed"
All of this news has prompted me to see where Boeing stock is at. Beyond the expected decline in price, I was more interested to find out how parabolic BA's price rise has been in the last 5 years.
Side note: I tried finding a site that would let me link out to a chart showing the full price history of BA. It's surprisingly difficult to find.
Basically they bet right on where the future of commercial aviation is going: more direct flights rather than hub-and-spoke connections, smaller jets that the airlines can fill completely, fuel efficiency is critical, and the air travel industry as a whole would recover after a pretty miserable first decade of the millenia. Their main competitor, Airbus, bet wrong, investing heavily in the A380 which hasn't found much of a market. That's been reflected in their profits lately: 787 and 777 sales have been quite robust, while A330/A350/A380 orders have been anemic.
Make sure you use a log Y-axis when looking at historical data. Steady compound gains (even just from inflation) will make any chart look like a 'hockey stick' otherwise. You're almost always more interested in relative price movement, not absolute.
Gains from 2016 have been good, but that likely reflects the clear success of the Boeing over Airbus's new aircraft.
I'm aware of the nature of compounding returns and inflation. Compare BA to other companies that have been publicly listed for a long time. KO, CAT, MMM, IBM, and so on. BA has had a markedly-parabolic rise over the last 4 years.
BA went up a lot in last couple years because there weren't any competition left and the demand for air travel has skyrocketed. They got 5000+ backorder for 737Max alone for regional. Then Airbus bowed out of the long distance market, leaving it to Boeing's 787.
The current fiasco certainly will put a damper to their stock,but there's simply no other choice for new planes. They will bounce back.
In this list of 737 accidents, correct me if I'm wrong, seems that the crashes for similar reasons (shortly after takeoff) are 3 , not 2. There is other one (May 18, 2018 ) involving a 737-100/200 that seems strictly related to the other two by time and dynamic: https://en.wikipedia.org/wiki/List_of_accidents_and_incident...
The 737-200 that crashed was a 40-year-old airframe, and the crash characteristics are only similar in that they all occurred shortly after takeoff.
The 737-MAX-8 crashes occurred within 6 months of each other, both on a brand new airframe on a new aircraft with a new control and sensor system that produced VERY similar profiles in rapid climbs and descents that point to an issue with said new autopilot.
The MAX-8 and the 200 are VERY different aircraft, even if they're fundamentally built around an original ancestor.
Yeah, but whether the hit is permanent or long lasting is still up in the air (unlike the 737 Max 8). On the one hand this could just turn out to be a coincidence or an easily fixed issue and Boeing's stock will rebound quickly. Or it could mean a massive recall of this model which will hurt Boeing for years to come. The current price is a reflection of this uncertainty and it could go either way.
It wouldn't surpise me if this were the final nail that shifted global orders toward the A320 Neo. Boeing has been putting lipstick on a pig with the 737 for 20 years now and people know it. They've only held out so long on their reputation at this point, and now that's in the gutter. The A320 Neo is an all around better, more modern aircraft built with computerized systems in mind from the ground up.
The 737 was a 30 year old airframe 20 years ago. Boeing was really trying to sneak past regulators on this one - reading pilot forums, people are also complaining about avionics updates that they didn't get any re-training for either.
The only commonality is these are both scandals and probably cover-ups - and generally negative headlines for both companies. The difference is there's been a significant death toll in the case of BA. You can argue the same for diesel emissions - but not really along the same dimension. ie: people dying of lung cancer vs people dying in a plane crash..
If you wanted to find the "fair value" price of BA you have to discount its future cash flows to the present. If BA planes are perceived as unsafe - what does this mean for future purchase orders? Does Airbus edge up ahead over time? Do people diversify their fleet with the new China-made jetliners?
From today's perspective, the stock is still in the middle of a crisis that is unfolding. It is impossible to know how much further down it will go as new data-points are revealed. How long will a fix take? Have commercial jetliners ever been recalled en masse?
Short-term trades are more fun than fundamental positioning, in this case, IMHO. Betting on continued high volatility via the options market is probably the safest way to go - as opposed to betting on directionality of the stock. Timing is everything. Happy trading...
They're basically like car recalls: You take the plane to maintenance and they swap out the bad doodad. Boeing had a very public one like this with the 787 batteries when it first launched; they made some changes and now it's an incredibly popular plane. But in general, they're happening all the time for basically every plane, just not catching much public attention.
It sounds like what you really need are flawless automated systems because humans will not always be able to compensate if the system errors are serious enough. And in this case they tacked on a kludgey flight control subsystem without adequate testing to see how it impacted the overall flight control, and did not bother telling the pilots. The executives probably did this to save money even though engineering told them it was unethical.
I'm curious to know how much civil disobedience there's been at airports once passengers realized they'd be flying a 737 MAX. With well over 100 people on a typical flight, and it only taking one dissenter to cause a disturbance that can ripple out to many more passengers, it may have been untenable to continue flying these anyway.
Sure, but you won’t get a refund for your ticket or your time. And some people might feel compelled to alert their fellow passengers if they felt the airline was planning to put them on a plane they felt was unsafe. These things could lead to anger, hence civil disobedience.
Do you honestly not understand the point I was making, or are you just taking issue with the exact phrase I used? And if the latter, state your preferred alternative and then pretend that's what I said. Maybe "consumer disobedience"? "Boycott"?
Honestly, this is tantamount to negligence by the FAA. This plane should've been grounded immediately and all of them checked for maximum safety. But the US, as dumb as always, just goes "nothing to see here", "we're waiting for data despite the data being 2 crashes where everyone died in 5 months".
So if over 200 people die on your watch in a statistically unlikely event, you're not going to re-check the planes? What makes US and Canadian pilots anymore worse than Indonesian and Ethiopian pilots? In the Indonesian case, it was a known software fault.
I asked yesterday on Aviation stackexchange https://aviation.stackexchange.com/q/61069/11524 whether the EASA and the FAA has disagreed on the airworthiness of a plane before. I doubt they did.
The FAA is ordering the temporary grounding of Boeing 737 MAX aircraft operated by U.S.
airlines or in U.S. territory. The agency made this decision as a result of the data gathering
process and new evidence collected at the site and analyzed today. This evidence, together
with newly refined satellite data available to FAA this morning, led to this decision.
The grounding will remain in effect pending further investigation, including examination of
information from the aircraft's flight data recorders and cockpit voice recorders. An FAA team
is in Ethiopia assisting the NTSB as parties to the investigation of the Flight 302 accident. The
agency will continue to investigate"
Their previous one, less than 24 hours ago, had: "Thus far, our review
shows no systemic performance issues and provides no basis to order grounding
the aircraft. Nor have other civil aviation authorities provided data to us that would
warrant action."
And Boeing recommended it, which was (finally) the smart move on their part. It's the only way to regain the public's confidence. If one more 737 Max had fallen out of the sky, it would have meant the end of the company. At least this way, Boeing is getting out in front of the problem. Better late than never.
Right move finally. Like I said in the post about Canada, at this point it's even better for Boeing. No one in the US wants to fly in this plane so it's better for Boeing if it's grounded.
I studied aircraft UX as my dissertation work. I’ll admit it is a few years out of date, but unlike JavaScript libraries, aircraft don’t change that fast.
Here's my understanding/analysis of the situation:
1. Boeing was under pressure to create a more fuel-efficient version of the 737NG to compete with Airbus's A320neo. The 737MAX was the result.
2. In order to be lower investment for airlines, it was critical that the 737MAX share a type rating with the 737NG. This meant that a pilot certified ("checked out") on an NG would be able to fly on the MAX without further certification.
3. To gain fuel efficiency, the MAX has larger engines. To first order, larger engines result in more efficiency: by accelerating more air by a smaller amount you leave less energy in the air that's exiting the aircraft. The larger and more efficient engines results in 14% less fuel burn. That's a major improvement!
4. The larger engines and their placement resulted in a "pitch-up moment" during certain flight regimes. What this means is that when you add a lot of power to climb, and/or during steep turns.
5. To compensate and – this is critical – to maintain the same type certification, Boeing added something called MCAS (Maneuvering Characteristics Augmentation) which nudged the nose down by trimming the stabilizer (the horizontal bit of the tail) down (which pushes the tail down and therefore the nose up). It appears to be activated without pilot input.
6. There are other mechanisms which also "trim the stab down" and there has always been a mechanism which disconnects them: pulling back hard on the yoke. This is a natural motion for pilots because in all flight regimes pulling back on the yoke pulls the nose up, which is what you want to if the nose is going down. There is a backup mechanism as well which involves flipping a pair of cutout switches and manually taking over.
7. My speculation is that because MCAS was considered critical to making the MAX fly "like" the NG, the first disconnect mechanism was removed on the MAX. This is critical bit #2: the obvious/intuitive mechanism to disable something pushing the nose down was removed.
8. Because MCAS was so important, two (?) Angle of Attack sensors were added to the MAX. These sensors appear to fail more often than they should. In aviation terms that might mean they work 99.99% of the time, not 99.999%.
9. So now you have a situation where an aircraft has a required mechanism to fly/feel like another aircraft in order to maintain a consistent type rating but which is reliant on a shaky sensor. And when the sensor fails, the mechanism has – purposefully – been made more difficult to disconnect.
From what I can tell, this entire set of decisions was driven by this type certificate/rating decision. That's the key mistake. I understand why this was done from a business standpoint, but if you're going to rely on manipulating flight characteristics it had better be bulletproof. Note that I'm not against the philosophy: Airbus has been doing it successfully for 25 years starting with the A320.
But this isn't bulletproof.
As it stands today, I wouldn't fly on the aircraft. Pilots are following this stuff pretty closely and are incredibly well-trained, but in a high pressure, low altitude, high wingload, high AoA situation, having them fiddle around looking for switches is a huge mistake.
I have never said this about an aircraft before.
I expect Boeing to re-enable the yoke disconnect and for the FAA to require recertification and a new type certificate for pilots to fly the MAX. Unfortunately, for Boeing, this will make them far, far less enticing to buy.
>To compensate and – this is critical – to maintain the same type certification, Boeing added something called MCAS (Maneuvering Characteristics Augmentation) which nudged the nose down by trimming the stabilizer (the horizontal bit of the tail) down (which pushes the tail down and therefore the nose up).
You reversed that.
MCAS is designed to force the nose down (that part is right) to counteract an upward pitching moment. That requires the leading edge of the horizontal plane to trim upwards, increasing lift at the tail, which pitches the craft's nose downward.
Southwest has more 737max than anyone else. However they have outfitted it with an optional avionics package that includes a HUD, an additional AoA sensor and indicator in the HUD and PFD, and an "AoA disagree" indicator light. (https://theaircurrent.com/aviation-safety/southwest-airlines...)
They also train their pilots using a 737max specific curriculum.
Why was a safety critical system (which was really only needed to place a bandied on retrofitting bigger motors on an older frame design) being sold as an "optional package". You need at least 3 redundant sensors in any safety critical system. This is just basic rocket science. Boeing and the FAA are negligent and should not be trusted.
With one sensor you have no choice but to simply trust the reading and hope for the best.
With two sensors you can compare, and if they disagree beyond some epsilon of tolerance you can fail safe by deactivating the system.
With three sensors, you can compare them, and if one is out of bounds vs the other two, you can fail operational by continuing to operate the system while also alerting the operator to the needed maintenance.
It's an AoA sensor. Planes flew without AoA sensors for 100 years; it's a useful sensor but not a critical sensor. Pilots and autopilots are perfectly capable of flying planes without it. If two AoA sensors disagree, you just stop making decisions based on the AoA sensor and fly the plane without it.
The crux of the problem is that the NG/MAX isn't certified to fly with malfunctioning alpha vanes. On the NG and MAX the effort required to move the control column varies based on the angle-of-attack (a.k.a. elevator feel system). On the MAX the airspeed calculation is influenced by the AoA and MCAS is triggered by data from a single alpha vane with no sanity checking.
Functioning alpha vanes are critical on the MAX and NG.
This could be true in avionics where availability and safety are more or less the same. In other applications where there is a fail safe mode like nuclear (stop fission) or land transportation (hit the brakes), you do not need that. The statement « any » is too strong.
Even think about distributed systems like databases. You absolutely should not call 2 db servers that are configured in a cluster as "redundant" You introduce things like split brain and broken quorum voting (not even possible without a third node) in the event a network connection is severed between them.
You can use 2 dbs if you apply the STONITH principle (Shoot The Other Node In The Head). Typically, when one node decides to be master, it can switch off with certainty the other one. Routinely used in HA (Highly Available) industrial applications.
That actually makes me feel simultaneously a lot better and worse that some party, especially Southwest, who in my personal travels has been my favorite airline, has been proactive with this.
But also kind of like "if a customer had some suspicions about some avionics weirdness or training, why aren't you as a responsible vendor understanding or addressing it holistically?"
That’s fascinating. It does seem to add a little credence that there may be a training problem with these planes, perhaps that Boeing facilitated this training “shortcut” when they shouldn’t have, and that the US / Euro carriers didn’t have the crashes because they go above and beyond with training anyway. All speculation at this point but I’m really interested to see where this ends up after the investigations are complete.
Hah, so I was right, in a way. They took the good without the bad. Except now these planes still grounded, so if they could have predicted this, perhaps they would have been smart not to buy them.
They were probably well into the process of purchasing the aircraft when they realized the extent of this issue, and might already have made financial arrangements that made them hesitate to back out. If this is a short grounding that is resolved by substantially the same measures as Southwest has already instituted, they'll look pretty smart. I wonder if airlines can buy insurance against losses due to problems with newly-purchased aircraft?
In fact, Southwest had very little choice purchasing new planes: their entire fleet are 737s (of various versions) so that they can lower personnel training & maintaining costs, which is part of the reason their prices are typically lower. So if they were to expand their fleet while still trying to minimize the cost they had basically no choice but to keep buying new 737s.
I don't blame Southwest though, after all the FAA and Boeing gave the green light for these jets. It would be interesting to see where Southwest is going if 737 Max is discontinued after this.
Note there are two sides to both coins: Southwest won't have such a good negotiating position with Boeing when it comes to ordering new aircraft, as they're much less likely to go to Airbus and buy A320 family aircraft (and even if Airbus offered a good deal, the logistical costs of moving to a more varied fleet add costs on top of that, and Boeing only needs to compete with the sum of the two).
I hope there's more to that upgrade story. I mean, micro-transactions are popular in video games but an optional feature that gives you +1 life in real life is almost unthinkable to put behind an additional paywall.
Maybe FAA should be grounded too, it's obvious to have the plane grounded based on the public data and patterns. Why does it take longer than that to make a decision.
It feels like there is an online service business idea in here somewhere. Some sort of way to verify the items that impact your life every day are safe and updated.
Does Boeing have the ability to disable the subsystem in the 737 Maxes that is the issue? (I’m not saying that this would be an alternative just curious .)
Probably, but from everything I've read to date on the issue, the feature is a safety requirement due to the increased possibility of nose lift during takeoff, which might create a stall.
So, 'just disable the trim' that has been throw around really sounds like they're disabling a critical feature, safety-wise, and while it's possible to fly the plane successfully without it, someone somewhere determined it was less-safe to do so.
I wonder if this will create a "land rush" situation in the aircraft leasing market.
Maybe not given that only 130 737-Max aircraft have been delivered to airlines.
Does anyone here know how aircraft leasing works in scenario like this? e.g. grounding of an aircraft model for an unknown duration, do airlines have the option so "switch out" currently leased aircraft?
Boeing 737 Max 8 has a different software system. That software is now a focus of investigators.
The Max 8 is outfitted with bigger, more fuel-efficient engines than earlier 737s, and the weight and positioning of those engines shifted the plane's center of gravity forward, increased the potential for the nose to pitch up after take-off. To counteract this risk, Boeing developed software known as the Maneuvering Characteristics Augmentation System, or MCAS.
Max 8s come equipped with a sensor that reads the plane's angle relative to the wind flow, prompting MCAS to automatically trigger the plane's nose to angle downward if it gets a specific reading.
However, problems could arise if the MCAS system gets erroneous sensor readings. The system automatically pushes the plane's nose down, potentially surprising pilots who are unfamiliar with the system and overriding their commands.This is what investigators believe happened to Lion Air Flight 610 before it crashed in October
>The Max 8 is outfitted with bigger, more fuel-efficient engines than earlier 737s, and the weight and positioning of those engines shifted the plane's center of gravity forward, increased the potential for the nose to pitch up after take-off.
Umm, a little confused here, if the center of gravity shifted forward, why will the pitch up tendency increase?
>Umm, a little confused here, if the center of gravity shifted forward, why will the pitch up tendency increase?
Because the center of thrust is also moved forward, and its effect is much greater than that offset by the center of mass. The 737 airframe was never designed to handle such powerful engines.
"If the Center of Thrust does not act through the Center of Gravity there will be a moment causing the aircraft to pitch, yaw or roll about the axes of the aircraft and the moment(s) must be counter balanced by design (including provision for trimming when the thrust is varied)."
Boeing chose to counteract that newly induced pitch moment with software, so that they could sell the MAX 8 to airlines as not requiring any new training or type ratings. And now nearly 400 people are dead because of a marketing decision.
If you move an engine forwards (or backwards) you are moving it along its thrust vector. Therefore the moment resulting from the distance between the thrust vector and the center of mass is unchanged.
It's also a vastly longer aircraft than originally designed: the -100/-200 are 29m/30.53m long. The MAX 8 is 39.47m long. (And the MAX 10 will be 43.8m.)
It's not the center of gravity that causes pitch-up - it's additional lift by engine nacelles at higher angles of attack; this lift increases the AoA further due to the position of the engines relative to the wing. This feedback loop leads to a stall when the angle gets high enough
Probably not completely true. An airfoil stalls when the critical angle of attack is exceeded. For most airfoils, this sits at around 17°. For all commercial aircrafts (I think 727 onwards) there is a mechanism called stick pusher that will not allow an airfoil to go over critical AoA. I am not sure if this has been overridden somwhere in the 737 Max 8 though.
I was describing the physical "bug" Boeing was solving in software: MCAS is a stick-pusher because it forces down the nose - which led to the Lion air crash because of a faulty AoA sensor made MCAS avoid an imaginary stall, forcing the nose down into a powered flight into terrain.
Are you saying 17deg from horizontal? Let's ignore wind and other influences. A normal plane can not climb more steeply than 17deg?
I'm not implying you're wrong, just very surprised to see this low a number. I would have guessed much closer to something like 45deg, maybe even more.
The Angle of Attack is defined as the angle between relative wind and chord of an airfoil. So if your engine has enough juice to climb at 45° (and many aerobatic aircrafts do), your relative wind is coming at 45° from ground, but almost at 0° with respect to the chord. So your wing is still flying.
I think it is actually that shifting the gravity forward makes the flight control surfaces more effective because they are now further away from the CG, but that's just from years of developing flight sims for the Navy, and no real knowledge ;)
It also could be with the engines moved forward from the wings a bit, their thrust tends to rotate the air frame "up".
You are right. Airframes are designed to be nose heavy. The wings tends to fly up, whereas the elevators tend to fly down. In a dead stick condition, the airplane is designed to fly with a pitch down attitude so you don't lose airspeed and have enough airflow over the wings to continue generate enough lift to glide. If the CG shifts forwards, it is actually a good thing.
The pitch up tendency is only increased at high angles of attack, at which point the engine nacelles themselves add extra lift, possibly inducing a stall when you're already near one.
The Center of thrust is offset down and somewhat in front of the CG, this means high thrust imparts a pitch up moment. Small, but present.
The bigger problem is the nacelles shape though, they create body lift at high AoA; imagine a vacuum bubble trying to suck the wing/nacelle backwards forming in the airstream, "pulling" them back.
Combine both of these characteristics, and you have an airframe demonstrating near stall positive pitch instability. I.e. you get a moment that if left uncountered will reinforce itself until the plane ends up stalling; behavior completely unprecedented in the airframe.
So in order to "counter" this behavior an automated system was introduced which supposedly restored the pilot relative flight characteristics in line with the old airframe's specs.
I'm probably oversimplifying, but it's the closest I can get to a visualization that makes some sense.
> The Max 8 is outfitted with bigger, more fuel-efficient engines than earlier 737s, and the weight and positioning of those engines shifted the plane's center of gravity forward, increased the potential for the nose to pitch up after take-off. To counteract this risk, Boeing developed software known as the Maneuvering Characteristics Augmentation System, or MCAS.
reminds a typical enterprise software project - deep serious issues stemming from screwed up basic architecture are hastily patched up by software patches. Sounds like it was a money saving architectural decision as development of more deep modifications to the airframe to allow for those engines to be positioned safely would definitely cost more than a software patch. And after the Lion crash the Boeing is doing patches for the patch ...
Regarding your point of bigger engines, I understood it differently.
The bigger engines provide a lot of thrust and with the new position of the engines, it’s a lot easier for the plane to stall. So the plane was outfitted with a sensor and software that reads the angle of attack and it corrects it in case the plane reaches the factor of safety angle.
If the sensor malfunctions, the software would get wrong readings and try to correct something that doesn’t need correction. It moves the plane nose down. Pilots correct. Process repeats. Hence the elevation fluctuations seen in Lion Air and Ethiopian Airlines.
Additionally, there is an optional feature to add a cockpit warning if the two sensors disagree, which could have helped the pilots diagnose the issue in the case of the Lion Air crash. The Lion Air plane did not have this option; not sure about the Ethiopian plane.
Awesome! Saves me time from clicking on the link and finding a paywall, or even hunting for the pertinent information :).
[edit: should've at least given credit though].
We've banned this account for plagiarizing from another source. If you don't want to be banned, you're welcome to email hn@ycombinator.com and give us reason to believe this won't happen again—and also that you'll follow https://news.ycombinator.com/newsguidelines.html in the future.
Don't understand the need for banning. I forgot to copy the link of news article.. Anybody can easily see that it is an official or news language and not a comment from me. It is copied from the below bigger article
Ok, we'll unban you. In the future, please use quotation marks or some other standard indicator (e.g. italics, which you can get by enclosing text in asterisks) to indicate that you're quoting.
Reading one of the pictographs in the article, it's noting that the heavier engines changed the aerodynamics of the plane in a negative way. Boeing engineers added what they call MCAS to counter these negative effects.
Now, I'm not an aerospace engineer, but common sense tells me that if you add something to a system that introduces a negative effect, you remove that something - not add something else to counter it.
That makes sense. Adding more things only complicate the system more and once the original "something" is changed or tweaked, now the rest of the system needs updated to balance again.
That's kind of a simplistic view, isn't it? By that logic you should remove the pilots, crew and passengers since they add a negative effect (weight) to the plane.
In medical instruments, we preferred to eliminate a failure mode rather than mitigate it (when possible). That's not the same as saying "just don't build the device".
Preferred how strongly? Eliminating the failure mode in this case means designing a whole new wing from scratch, which is nearly the same amount of work as designing a whole new plane from scratch. So Boeing's alternatives (while maintaining the same efficiency) were to completely replace the 737, or fix the issue in software. The latter option is obviously vastly less expensive. If you're confidence in the software fix is high, it's probably a reasonably choice. In hindsight Boeing's confidence may have been misplaced.
It depends on your optimization points. No people moved=no business transacted.
Regardless, I don't find the poster's logic to be unreasonable. However, Boeing was additionally constrained by available engine hardware. It's just a whole Charlie Foxtrot of a situation.
That's exactly my point. The statement "if you add something to a system that introduces a negative effect, you remove that something" is borderline nonsensical in any kind of realistic engineering environment.
Let's be clear about what is happening here. This is simply a 'not on my watch' and 'CYA' philosophy that is what society has become today with so many news hungry sources and social media. Anyone in a position of power is so worried about getting blamed by irrational people for a bad outcome that they will simply make a choice to prevent that from happening at any cost. This doesn't mean that it's the wrong choice. But the fact is all anyone has to think is 'wow if this happens a third time I will get blamed'. [1] The old 'abundance of caution'.
The fact is at what point do you do this? What about an extreme. Like every time there is any crash just ground every single plane until the extensive investigation is done?
[1] And it should be irrelevant what has happened in other countries as far as grounding as well. Assumes they have concluded something and have more facts which of course they don't.
Edit: I love when people who comment on HN based on what they read feel that they know more about the actual risk than the people (per my reply to a comment) at Boeing.
I don't feel this way at all. The more we learn, the more it seems like Boeing misrepresented the extent of the changes they made inbetween the 737 and 737MAX8/9 models in order to avoid recertification, then undereducated the pilots about those changes.
As a consumer who has flown on these plans many times, I'm glad they have been grounded until a fix can be deployed.
Engines are also very different between 737 Original and Classic, so having different thrust vectors between generations is not happening for the first time.
And exactly my point. The parent comment stated a fact that could be true or not be true. And it's almost certainly something they read and therefore interpreted as significant an important fact. And that was what I was saying. All the info you read regardless of whether it is quoting an expert or not [1] comes 2nd hand and with nominal validity vs. people at Boeing being in a position (by the fact they employ and have access to actual experts) much better able to assess the danger. Of course I don't know if what you are saying is correct but that doesn't matter for the point I am making but thanks for making it just the same!
[1] Which assumes the expert is even being quoted correctly which as anyone knows is not always the case.
> The fact is at what point do you do this? What about an extreme. Like every time there is any crash just ground every single plane until the extensive investigation is done?
Not sure why you jumped to the end there, as if asking "at what point do you do this?" is a ridiculous conversation to have. I think it's a reasonable question to ask. It seems like for most people the answer is somewhere between "ground all planes any time there's an accident" and "ground a new model that has has two accidents in six months".
Most of the world operates in shades of gray and nuance. Having the discussions about where the borders of nuance lie and why is valuable.
It’s a reasonable question, but any comment that even remotely appears to “side with” Boeing is now downvote-bait. There isn’t much room for reasonable discussion on this thread.
I think it's reasonable to assume that Boeing has a great deal more to lose than anyone else in the decision chain. The idea that they would bet the company if they felt there was a safety problem is extreme. If there is another crash or two they are toast. Certainly any rational business decision maker would take that into consideration as far as grounding or not an entire fleet. Given that, it's actually amazing that they don't just err on the side of caution in the off chance there is another crash even if that crash has zero to do with the plane or any defect (since it would not be known right away if that was the case).
Lastly as someone in another comment made the other day not flying a 737 Max 8 means potentially flying an older plane or some other circumstance that in theory is more risky (even driving).
Actually the opposite is the case. The aircrafts should have been grounded world-wide Sunday based on the available information and flight path, to err on the side of caution. The U.S./FAA now look like idiots and are trying to save face.
It's easy to talk in the theoretical but when planes have crashed loosing all hands and in similar circumstances pausing and taking a look at the data is the best course of action.
Planes are grounded precisely because there is no information.
If we had information, then there wouldn't be a grounding (because we can rule out design flaws, etc).
When you are driving in a snow whiteout do you not slow down or even pull over? Or are you one of those people who would drive at the regular high way speed limit while not knowing what's in front of you?
This is not that extreme scenario so what is even the point of bringing up? 2 brand new planes crashed under similar circumstances. It makes no sense to wait til the conclusion of the investigation to ground. That has perverse incentives to hurry an important investigation.
I really don't understand this argument at all. 350 lives have been lost. That means something. This isn't reactionary. There's something wrong and people need to look into it. For now, stop flying those planes.
I find it scary that Trump had to issue an Executive Order to get this to happen. It tells me that the FAA no longer cares about safety, but is more interested in corporate interests over the lives of 180+ people at any given time.
Is there anything he can do to get any positive approval? I am not american but from outside point of view it seems like in every thread or news comments section it seems like even if Trump saved 50 babies from a burning house people will still find a reason to blame him and search for a bad motive.
Getting off Twitter would probably boost his approval by a couple points.
People can and will disagree with policies regardless of who or what is in office. But the way he conducts himself and the people he surrounds himself with really push people the opposite way, though at the same time it's distracting from some of his less agreeable policies.
This seems to be a distinction without a difference given how American politics works. You don’t need net positive approval to get elected, as evidenced by Trump’s current position as President. For this reason, it makes more sense in this context to say Trump does have positive approval from 4 in 10 Americans and the claim that “the world / media / etc” are wholly biased against him no matter what doesn’t hold water.
What do you think about that tim apple interaction? If you see proof that the president lies, to doners, and media, does that sow any hint that he is not honest? Credit is easy to lose.
A big part of his image, both admitted and admired, is essentially being an asshole. This is unusual, to say the least, and it can't be surprising that the reactions to this president reflect that.
Since this was Trump who issued the grounding order, can we finally dismiss all the previous HN comments of people saying the FAA and Trump are in cahoots to keep 737 Max 8's flying in the US to prop up Boeing.
-- Edit --
Apparently not. Now all the comments are blaming the FAA and saying it is fishy it took an executive order.
I think it's the lack of information that's scaring people. We don't know why the Ethiopian flight went down, it's just really suspicious that 2 brand new airplanes crashed catastrophically so soon after delivery.
I think it's a good move until we know the full picture though. Better to err on the side of caution when lives could be at stake.
Everyone seems to be zeroed in on MCAS. Completely unknown at this time whether that system was related to the Ethopian crash. What the two crashes do have in common other than the aircraft model is a third world carrier, dubious pilot qualifications, and heavy reliance on automation. But it's somehow not OK to talk about that.
Ethiopian Captain had over 8000 hours, and the airline is a Category(right word?) 1 Airline, able to fly into and out of the U.S. directly. They actually have a stellar safety record.
Just because it's Africa doesn't mean the operators were lacking.
If these planes are being crashed multiple times per year, even if by less experienced operators, then Boeing is still at fault for designing an unsafe airplane. Other planes do not have these issues.
Why wouldn't it be plausible that Trump and the FAA were inclined to do whatever Boeing wanted, but eventually every other country grounding the planes made that position untenable so Trump was forced to change his mind?
To me, this is the most likely scenario. Boeing assures Trump the planes are safe and they'll take care of it, time passes and the US stands alone, people freak, Trump realizes this and then steps in front of the cameras to look like the "protector".
What's silly to me is how Boeing doesn't realize that another crash IN THE US would be disastrous, much, much worse than the position they find themselves in now.
It's possible that US maintenance procedures and pilot training make it very unlikely that a crash would happen here, even though depending on perfect maintenance and defensive piloting shouldn't be necessary for an airworthy plane.
(Guessing upon all available information) It seems that something is wrong when the auto-pilot is turned on... And this seems to happen a few minutes after the take off...
Official rulings aren't in yet, so this is all wild speculation, but the dominant hypothesis appears to be that these new planes are equipped with MCAS ("Maneuvering Characteristics Augmentation System") software that is supposed to account for inherent aerodynamic instability in the design by making it much harder for the pilot to accidentally crash the plane.
Without going into too much detail: there are many tradeoffs in airframe design, but one of them is fuel efficiency vs. inherent stability. Some airframe designs eke out a bit more miles-per-gallon at the cost of having ranges of motion where if the pilot gets the plane into that state, the feedback loops on motion become positive and the plane is likely to tip over, stall out, spin, etc. Boeing's Max-8 design makes this tradeoff, and the MCAS system is supposed to help compensate for this design by forcing the pilot to nose the plane down (to improve airflow over the wings and generate more lift) if the plane is pitched too high.
Problem might be that MCAS can malfunction and think the plane is pitching up when it's not, and if the pilot can't figure out how to disable it, they get very confusing signals--- they're pulling back on the stick to get the plane to climb, but MCAS is pushing the stick forward to avoid an expected stall that a malfunctioning sensor is telling it will happen. End result: pilot and the computer fight each other while the very important business of "keeping the plane in the air" isn't done and the plane crashes.
It sounds to me not just a software issue but a systems issue where software, hardware and architecture play a role. What used to be a sensor to measure the angle of attack became suddenly key input, single source in a short term control loop for the most vital axis. What could go wrong...
Taking into account the other sensor data is an obvious choice. A better understanding the quality of the sensor data in real field operation may also be required. Clearer stabilization problem indication, quicker manual disengage of auto pilot (several reports of nose down events) and MCAS are others. Decreasing the allowed tail trim for MCAS is another.
Then that leaves: Another one or two sensors. Independent review of the engine control laws (report of unexpected low thrust when climbing).
There is a lot to be done. The plane was rolled out too early and fixing the cut corners for real could take a while.
If the plane is indeed unstable, and a pilot turns MCAS off due to a malfunction, can it be flown by a pilot who is not specifically trained in the manual management of the 737-MAX’s instability?
It wasn’t inevitable; if it happened solely because Trump made them do it (edit: the article now seems to contradict this, but did not when I wrote the comment) it’s truly a red-letter day for rationality and evidence-based reasoning.
The conversation around this subject has degraded to irrational hysteria, but really: do you think Trump knows anything about airline safety? Is this really how we want the system to work?
Today it’s an airplane model, but tomorrow it’s banning travel from Africa because of an emerging disease, or capitulating to anti-vaxxers because of a news story.
Yeah, the article seems to be changing with new information.
If Boeing requested it, it’s obviously a different thing, but it wasn’t clear at the time I wrote the comment, and the original comment was phrased conditionally anyway.
I mean.. the guy did own and operate an airline at one point. So it's a little silly to say he knows nothing about it, no matter how much you don't like the guy.
I mean, he also claimed that newer airplanes are less safe than older airplanes. Which seems pretty absurd given that crashes have been trending down for sometime.
> I mean.. the guy did own and operate an airline at one point. So it's a little silly to say he knows nothing about it
Given the way that worked out, his having owned and operated an airline is certainly evidence that he had money, but not evidence that he knows much about even the business side, much less any other aspect other than the "being a passenger" side, of aviation.
Trump certainly wouldn't have been the only person to end up owning an airline that was more the money than the brains behind the operation...
Based on transcripts of him talking to airline industry executives[1] in the past, I'd say he actually knows less than nothing: i.e. he doesn't know what he doesn't know, much like the pointy haired guy who's too insistent he wants you to get the robots that write the computer programs to make a blockchain for cybersecurity to read your explanation of the bug.
That it took the president to do this is a pretty awful condemnation of the FAA. Maybe he shouldn’t have appointed an industry lobbyist to the position in the first place.
The whole software is made in India and now is said having major software flaws. This is not the first time.
The rest engineers in Boeing, many are not longer first class, they got their jobs because of race and gender.
Your future heart doctor might be from the best medical school, but they might get in either by bribery or worse, by AA(affirmative action), they're not really up to the job, and they may kill you with good intentions without you knowing it.
Let the merited-based engineers do the most critical designs in this country please, people actually are different. For those who thinks everything should be absolutely equal, while that thought make you high whenever you think about it, you and many others may get killed by that ideology.
The reactions of Boeing (and potentially the FAA) deserve much more criticism than the actual mistakes which led to the crashes. Accidental mistakes/oversights are expected and can be forgiven. Thoughtful responses which seem to have attempted to put profit above moral standards cannot be forgiven.
Many other thoughts...
-People, including executives, seem to have a very hard time thinking big picture. Q4 2018 financial results seem so important only in the time period around Q4 2018. History doesn't care about Q4 2018. History will care about the crashes (especially the second, more preventable one which happened while Boeing was working on software fixes "to make a safe plane safer")
-Overall, it is bizarre living through and watching these two crashes and the reactions to them in real time. I've often watched episodes of air crash investigation shows, the most interesting being series of crashes of the same aircraft models from decades ago (before I was in adulthood).
-No doubt that Boeing will be viewed negatively in historical light. Their culpability was sealed with their reaction to Lion Air, and only further worsened with their reaction to Ethiopian.
-I think the worst possible outcome for Boeing will be if it is determined that the MCAS issue is nonrecoverable even with the instructions that Boeing has repeated.
Still curious... what made the FAA and Boeing switch sides on this issue?
1. Was there new information? (Satellite data, etc)? -or-
2. In the inevitability of a ban, is it just a better look to seem "proactive" than to go down kicking and screaming?
I think we should also lay some blame on the airlines as well. Why should they have accepted such planes in the first place? Don't they have their own engineers and safety inspectors to counter-balance a plane company's marketing department?
More so, I hope there are subpoenas of Boeing's internal communications regarding this matter. Rumors I have read elsewhere indicate some real skullduggery if true.
Lastly, it really calls for the need of independent software auditing and compliance. There should be no proprietary software operating in regulated airspace.
I’m not necessarily arguing his case, but if their software was open source it could be scrutinized far more closely. Is this software actually audited at all before an accident occurs? Do regulatory agencies have the bandwidth to do that? I really wouldn’t be surprised if this (and a lot of the embedded software in cars as well), simply isn’t being thought through because of commercial pressures.
The whole "enough eyeballs make all bugs shallow" thing is an empirical falsehood as evidenced by all of the breathtaking security bugs discovered in open source software over the past decade or so. It's not just anyone who is qualified to do auditing. If the software needs to be audited more carefully, the solution is to find the people qualified to do so and have them do it. It is almost completely unrelated to whether or not the source is open, which I'm also not against and in fact would be all for. However, arguing that proprietary code is inherently dangerous and open source code inherently safe is incredibly dangerous of itself and needs to be shut down.
You're confused about open source software and security.
If a business is using proprietary software that is found to have critical security bugs, they are 100% beholden to the vendor to get a fix. The vendor may decide to not fix that bug.
With free software, when (not if) a bug is found, the user has the right to fix the software.
While 'open source' might not be inherently 'more safe' than proprietary code (which we can't audit, so unlikely to be safe), it's inherently more safe due to the fact that the end user might actually be able to fix it, if required.
I didn't say that and the poster above didn't say that, but having the source available would undoubtedly help. In this case in particular you would have had many groups looking at the code in parallel, rather than the need for a slower, closed process because of commercial sensitivity. If both crashes end up being linked to this system, then the fact the code wasn't publicly available would likely have contributed to the inability to prevent the second crash.
You can’t say that though. For one thing code reviews are almost hopeless for catching normal bugs in the first place. For another, just because code is available does not mean anyone is actually looking at it. The people who are qualified to do this stuff quite likely will not do it for free.
This is about investigating one particular widget which has been implicated in these crashes, had the source been available people would have been able to look at exactly how that system works over the last months, rather than speculating while they wait for the closed investigation to occur, and while they wait for the second accident to occur. This isn't a general 'bugs will be found', it's about being able to substantiate targeted suspicions about a particular part of the code.
let airbus.controls=Object.assign({},boeing.controls};
airbus.controls.yoke=undefined;
airbus.controls.headings=joystick;
airbus.controls.safety=basic_law;
The fact that Boeing cut as many corners as they did to bypass mandatory training just adds more smoke to the fire. When the dust settles on this episode I won't be surprised to learn that Boeing (and FAA regulators) is found completely at fault for engineering shortcuts to save costs on re-training.