https://graphics.reuters.com/BOEING-737/0100B2J51TY/Boeing%2...
The system affects how the flight stick feels and that's really it. The more you pull up (higher AoA), the more force is needed on the stick. That's supposed to be linear within some margin of error. The big fat new engines took it out of the linear envelope, making it a bit lighter than it 'should' be at high AoA as the engines caught the wind. They either fixed this, or else needed a new type rating (pilots can't hold more than one, so it's a huge issue for existing operators of 737s).
The solution was MCAS which, as originally designed, wasn't powerful enough to cause problems. But test pilots said that the stick was still a bit light, so they reworked it and made it way too strong, while still being invisible to pilots and lacking the reliability of a critical system. Then several hundred people died.
You can hold more than one but you need to maintain each separately.
I kept hearing this too, so I wondered why they didn't just directly change how the stick feels, like with a force feedback system?
And I looked it up[1]: Turns out MCAS was also there to push the nose down at high AoA, to imitate what the 737 NG does even in the absence of control input, so it's not just a stick feel thing.
"The added nose down trim has the side effect of requiring more elevator input at high angles of attack", so simultaneously fixing the stick feel issue.
It seems to me like MCAS solved two related problems at the same time... and sadly thus created an even larger unintended problem.
The transcript (https://tmsnrt.rs/2OZl4Ic) shows them specifically talking about MCAS doing weird stuff in simulators and they they didn't know what was going on, or what the expected behaviour was. Interesting that it happened in a simulator where I presume that sensors don't sporadically break or deliberately give duff readings in what is probably a lot of highly controlled tests... perhaps a pure software error?
Did this problem just get lost somewhere in the noise of development? Was it "unreproducible" (in the bug sense)? Was it willfully ignored by "the management"? Who knows - but we now do know that some people at Boeing involved in development were aware of problems before the crashes.
Pretty sad really.
You could suggest that the trim system is defective regardless of MCAS. That the pilot should always be able to counteract automatic trim in any flight mode.
Or the problem is solely in the max modifications and you can safely ignore issues with the original design.
This sorta worked as long as Boing built consumer aircraft that worked exceedingly well. But alas...
People need to go to prison over this.
>Forkner said in one text message, “I basically lied to the regulators (unknowingly).” The other employee responded that “it wasn’t a lie, no one told us that was the case” of an issue with MCAS.
>Forkner responded soon after: “Granted I suck at flying, but even this was egregious.”
The one about MCAS running rampant is clear enough but what does he mean saying that he sucks at flying? What is egregious?
Interesting that prison time is demanded here when a much more simple explanation is that this was an oversight by the pilots in the sim who didn't fully understand the issue was MCAS related.
Millions killed from opioid epidemics, thousands killed from violence and various preventable diseases, huge number of road fatalities do not result in prison time.
The safety record of aviation in the US should be applauded.
Cold comfort to the 300+ lives, and families destroyed.
Watch this video: https://www.youtube.com/watch?v=H2tuKiiznsY
This isn't just some "oops, these were badly trained pilots" – the whole premise of MCAS is seriously screwed up and smacks of non-engineers running the place.
It kinda turned into a reverse-merger, where MD bosses took over Boeing and heavily influenced the management style and practices thereafter.
Some of the commentary https://newrepublic.com/article/154944/boeing-737-max-invest...
There's deaths caused by Boeing's greed and lack of competition against Airbus' new planes.
There are serious questions to be answered about the corporate governance.
Maybe someone should go to jail here, but I doubt it.
I see no reason not to hold key decision-makers responsible for the consequences of decisions that aren't just misguided or incorrect, but actively and wilfully negligent of factual information - especially if they cause even more deaths by attempting to suppress that information and place blame on innocent parties.
It is not clear what they were testing - perhaps they were indeed testing the MCAS system with sensor failures, but if so I probably wouldn't have expected such a surprised resction from them. It seemed like it was totally unexpected and unexplained, which is not a reaction I would expect if they were testing this.
Those are the pilots words and he’s saying the messages are being misinterpreted and cherry picked without context.
He's acknowledging that even with all his experience, he could be wrong -- but clearly he wasn't.
I don't think it's all that easy who is responsible.
https://en.wikipedia.org/wiki/Buck_passing#%22The_buck_stops...
If the CEO's are held responsible for the deeds of the companies they lead you can bet that there would be an instant improvement of corporate accountability.
I've seen up close what even a little bit of accountability can do to large organizations, something a bit stronger would surely still have a positive effect.
As for whether the engineers will also be responsible: REAL engineers already carry responsibility and do so without any problem at all because they know their fellow engineers would not do any different. Professional integrity that's called. Software does not even come close to those standards, nor does most of tech.
And aviation - supposed to be different - went downhill in a hurry in the last decade and a half, not too late to turn back, though for Boeing it may very well be too late to recover their reputation.
The mindset of "quick to imprison" can also run the risk of creating a society that is overly averse to risk taking, which can hinder technology and scientific advances. For example, it may take 10 times as long to get a new, more advanced traffic light implemented in your city because now everyone wants to make sure no stone was left unturned, otherwise someone will get into an accident and a staff/group will be imprisoned. Or a new software is implemented but 3 months later it is found that failure under very specific scenarios has caused over 50 deaths. There are millions of potential scenarios that may fall under similar conditions as exemplified above.
Please note that this writing is not advocating for or against either views, it is simply shedding light on risks that should be considered.
The result is that developing new drugs got enormously more expensive, far fewer new drugs get developed, long delays in effective treatments getting approved, diseases that don't affect large numbers of people don't get cures developed, etc.
The net result was a negative for patients.
This was all discussed in "Regulation of Pharmaceutical Innovation" by Sam Peltzman.
There have been a lot of deadly aviation crashes due to mistakes, false assumptions, oversights, incompetence, human failings, etc. But somehow we've wound up with incredibly safe airline travel. Millions of flights with no incident. Do we really want to start jailing people now? What improvements will we forsake if we give airframe makers powerful incentives to hide mistakes? or simply avoid making improvements to safety, because who wants to risk jail for making a mistake?
If you wanted to reduce auto accident rates, opiod deaths etc you'd put these folks in charge, not put the law enforcement lobby in charge (yes, they will arrest lots of low level offenders but will not systematically address the issues and do not chase the folks at the top).
Not only that, it beats almost all other regulated modes of transit and even other regulated hazards (OSHA controlled worksites etc).
As always, it could be better - but it's actually amazingly good already - these planes are incredible safe in a challenging environment (miles, landing cycles, tolerances etc).
The demand for prison time here, when we have so many many areas where prison time can be MUCH more closely and immediately linked to bad actions (and goes unpunished) is misguided.
If you look at where fault lies part lies with boeing and part lies elsewhere in the safety chain. In contrast to many other areas - the evidence of ill intent is relatively weak here. Even without prison Boeing is facing major financial impacts as a result of this issue (as it should).
It's looking like evidence from the airlines that proper maintenance was done may have been faked.
https://www.bloomberg.com/news/articles/2019-10-15/pictures-...
We know lots of maintenance issues unaddressed and repeated warnings by the plane itself that there were sensor issues were not properly addressed.
We know response was not ideal on pilot side which overlaps with some training and other items around stab trim cutoff and/or automation dependency.
These factors are partly why there have been no accidents in 737MAX in US despite lots of flying.
Yes - boeing should design a totally safe plane. Part of that is going to be designing plans to accommodate a wider range of pilot skill (what they are calling "future pilot populations") and to better accommodate maintenance and ground handling training assumptions to allow for greater risk of problems there. This is already being implemented.
Ironically, one element may be to REDUCE the reliance on pilots as a key flight safety control and then increase automation and redundancy in the automation.
By what metric?
By every metric I can find (passenger deaths per trip/flight leg/flight mile, hull losses per delivery/year, etc) the MAX is an outlier.
In fact, I can't find any other airframe in the last 50 years that even comes close (including the DC-9 and TU-154). What other airplane has killed 300+ passengers in its first 4 years of operation?
So, what metric have you selected to show that the MAX isn't dismal?
(and please, no lie-with-statistics stuff like hiding the MAX in 737NG data, or claiming that crashes by foreign pilots or on foreign soil don't count)
Most people are referring to negligence, not ill intent. "Let's make more money and rush this thing out! (Even though this could kill people)", not "Let's deliberately design a system to kill people".
Regardless, one sensor failing should not induce a plane to fly itself into the ground, despite the best efforts of the pilots to recover (and despite the fact they were not necessarily the best trained pilots). 2 / ~400 complete hull losses of brand new jets is completely unacceptable. That is dismal. Don't try to downplay it.
Absolutely - Boeing is going to be designing much safer planes in future to accommodate different pilot populations. That is clear and necessary. This will make us all safer. Boeing obviously screwed up with a primarily US based mentality.
This system was PARTICULARLY fragile in the face of poor maintenance and reliance on automation - which boeing was unreasonably dependent given a US centric view.
Look into history of comets and concorde if you want to look at hull loss rates (note - both stopped flying forever when safety issues became clear). I predict almost no chance that the max will be taken out of flying forever.
And part 121 planes in the US do not fly multiple legs with the problems described on these planes.
I know it's partly a labor issue, but mechanics at united will take a plane out of service for practically any reason.
https://en.wikipedia.org/wiki/Southwest_Airlines_Flight_1380
Airbus has hardly been free of dangerous flaws. Watch "Air Disasters" on the Smithsonian channel.
Management culture needs to change. Feral greed needs to stop being seen as an acceptable excuse for unacceptable behaviour.
Nobody seems able to write software that doesn't have bugs in it, in fact it seems to be humanly impossible. So, if you're going to jail people for buggy software, no new software will get written.
The same goes for airplanes.
Rules without accountability and enforcement are meaningless.
Standing over people with a sword is not going to get you any risk taking. All aviation improvement, including safety improvements, will come to a dead stop.
And they shouldn't be. But there is a very large difference between 'mistakes' and 'intentionally circumventing processes put in place to ensure safety'. Having to draw lines is always difficult, but in this case the line has been crossed. Consider what Martha Stewart went to jail for, then compare to what happened here. If justice is to be observed as even handed there ought to be some serious consequences here, not some already rich guys getting richer with their golden parachutes, the irony of which I'm sure will not be lost on the relatives of the people who died.
Seeing how Boeing stock is doing, they ain't getting rich on their stock options.
> Software development for aviation is pretty good, that's not where the issue lies here.
MCAS is a software system, and the rules programmed into it had human factors mistakes in it.
You might want to read Aviation Week, 19-Aug, for more detailed information.
1. MCAS does not behave exactly like a normal runaway trim.
2. On the Ethiopian crash, they _did_ initially follow the stab trim cutout procedure, but they didn't manage their speed correctly and thus were unable to control the plane with manual trim.
IMO point 2 is very important - pilots will not always be perfect. It's easy to armchair pilot from your couch and say that "Oh, just manage your speed correctly when your plane is trying to pitch itself into the ground just after takeoff and follow the stab trim cutout procedure. Very easy to deal with MCAS." But reality is not that easy.
> Look into history of comets and concorde if you want to look at hull loss rates
Compared to every other new plane released in the past 20 years, the 737 MAX has a terrible hull loss ratio. I don't really care about the Comet or the Concorde since it's 2019.
Pilot error still #1 cause of fatalities including in the US. In this case bad maintenance also looks to be an issue and a brittle design. You have a master caution on 4 seconds into flight - you've got a terrible maintenance log book etc. I actually thought initial stab trim call wasn't unreasonably delayed - though they did let it run 4.6 to 2.1 over 10 seconds or so, which is a HUGE trim change.
And stab trim cutout wasn't followed fully or MCAS wouldn't have been able to put them into the ground at the end, though they may have already in a bad spot so thinking not unreasonable, except of course you might sit on nose up trim for a bit once reversing cutout.
The move will be I think to more automation and reducing ability to dispatch with things like a flight computer out of service (histrionically pilot skill would cover this now).
I also think they may need to move to authenticated maintenance / self test / parts life / history items. Ie, prevent dispatch on sloppy fixes / sloppy test.
I think evidence will show you're wrong. The MCAS is a terrible design no matter where you intend to fly it.
In the US, efforts in last years have focused on the entire chain of safety (actually away from plane design) and the US has hit some of the BEST periods of safety in aviation. This is everything from duty / rest periods, maintenance, minimum training requirements etc.
"And this is somehow OK for American pilots, but not for foreigners?"
Let's be VERY clear here:
The requirement to fly Part 121 in US even as just a first officer requires an ATP and 1,500 hours. Most folks have a a significant amount of other flying prior to that, the US has a much bigger GA aviation scene, private flight instruction, glider, private jet / charter markets and military flying. The US has something like 12,000 pilots flying for the air force alone. The first officer on your long flight is very very likely to have a TON of experience in all sorts of situations, and particularly with manual flying.
Overseas - you can be a graduate with an academic / training background only and 250 hrs of "flight time" more broadly defined and be at the controls. Ethiopian airline pilots were 25 and 29 years old.
In the US, major carriers even more picky.
Southwest for example:
Flight Experience: 2,500 hours total or 1,500 hours Turbine total. Additionally, a minimum of 1,000 hours in Turbine aircraft as the Pilot in Command* is preferred. Southwest considers only Pilot time in fixed-wing aircraft. This specifically excludes simulator, WSO, RIO, FE, NAV, EWO, etc. "Other Time" will not be considered.
So yes, if boeing is going to sell into markets with folks getting into cockpit as co-pilots with sometimes as low as 50 hrs (1 week) of experience (in cadet / training systems) then 100% they will need to redesign and rethink things for this future pilot population - and yes, that means the systems will have to have MUCH more natural redundancy built in.
Ignoring this difference in background, opportunity and skill will lead to lots more deaths - all preventable if the thinking changes and a better understanding of future pilot populations is developed, and that includes accounting for differences in training and experience.
In fact, even the Southwest pilots you mention disagree with you: https://www.seattletimes.com/business/boeing-aerospace/in-sc...
You're still trying really hard to blame the pilots and ignore critical and unarguable airframe deficiencies. It hasn't worked yet but maybe if you keep writing lots and lots of words you'll get somewhere.
I think you are failing to understand how the chain of safety works. Ideally you have a great design. If you don't then ideally the flaws / weaknesses don't get hit because you have things like good maintenance. If you don't have that then maybe next hope is the pilots. Worst case you then you require instrumentation to help reduce risk of the next tragedy. Etc.
This system has resulted in an incredibly safe mode of transport despite many challenges / crazy tolerances etc.
American pilots are top notch. However, the pilots themselves don't want to be put in the position of saving the aircraft, and a big part of the FAA's charter is to ensure that they don't have to.
Does your chain of safety include feeding a twitchy automated system from a single sensor?