I’m thinking it might be better all round if they create a clean sheet design. Of course, Southwest won’t want that any time soon.
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My aviation prophesies rarely match reality. With that said, the simple answer is that the Max will be rendered completely safe*. MCAS will be so weak and dumbed down that its ability to do meaningful harm will be nil. (It should be removed entirely but pride and further liability will prevent that.)
So yeah I think the Max will be back and people will fly it. The FA’s can want whatever they want. They haven’t a clue. If making noise makes them happy, fine. What will be really interesting is what happens outside the US. The FAA has proven to be a very poor agency of oversight. Other countries will need to flex some muscle and show their public that they are not just buying into whatever America is selling.
*Why am I so sure? Because it is still a 737–the simplest modern mainline airliner built. It doesn’t need electrics. It doesn’t need hydraulics. The 737, in the hands of a trained and experienced crew, can plow through failures that would lawndart nearly any other airliner.
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Training? That is the billion dollar question. The whole reason for MCAS was to allay any need for extra sim time. Will that pitch work now? Time will tell. To my knowledge, there is not a single Max simulator in the entire US outside Boeing. How’s that going to work? How are the airlines, FAA and Boeing going to sell this to the public? Grab some popcorn because the next couple of months will get very interesting.
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It seems like a lot of this was because Boeing assumed that pilots would immediately recognize what was going on and take the needed steps to prevent what happened.
The problem is that not all airlines are created equally as far as training and maintenance. The lesser ones were going to run into this.
There are 2 schools of thought–make a plane so automated that low-level pilots can work it, or make it so manual that pilots with sufficient training can do everything.
We’re seeing what happens when the former falls short.
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Anyone who’s suffered through this entire thread knows how hard I have struggled to explain why the sequence system failures that led to the crashes would have been so utterly confusing to ANY crew. If it helps I will restate:
I give MYSELF a 50/50 chance of surviving the LionAir event.
In order to understand why you have to understand SPEED TRIM. It is the existence and constant activation of that system on ALL 737s that would have made recognition and recovery of the secret MCAS activation difficult. And let’s not forget the whole horror of bells, warnings, stickshakers and impossible displays that compounded the confusion and panic.
This event did not expose insufficient training or marginal pilot skill. It exposed a series of bad design decisions and a system kept secret from pilots. After 20 years flying the thing I wish I could come up with some way to make this clearer for non-737 pilots. It has been a year and it still breaks my heart.
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Everything I have read points to this.
It was not a case of “lesser” airlines or “low-level” pilots being unable to adapt, it was the case of Boeing not wanting to require pilots to retrain on the ‘new’ version. If you don’t have the training, because Boeing says that you don’t need the training, you don’t know how to handle an issue in a system that was not documented.
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And it was not as simple, or blatantly obvious as a standard runaway trim scenario.
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After having flown on a MAX, I am getting the feeling I’d rather them make a new design than fly on one again.
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On the treadmill just now I came up with a nice “thought experiment” to help explain better why the crashes were such an outrage and also why the planes can still be among the safest airliners in the sky. Give me a couple of hours…
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As a non pilot, but a person interested in technology and its failure, I am very interested in the cause and outcome of this. I believe these statements made for example by you, smoke. Or Juan Browne (blancolirio) on YouTube.
The interesting thing is: How will stoopid hoomans deal with this massive fail, and how will its aftermath look like. Will we learn more than just correct a plane model. Pretty sure we will, but to what extend? Prices going up is one indicator I‘ll be watching.
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Money is the only thing.
Boeing designed the MAX instead of a clean-sheet because Airbus was getting 32xneo sales that were also not clean-sheet. It had customers saying “we need something NOW.”
Unfortunately, to get the plane to have the efficiencies it needed and be cost-effective meant the plane wouldn’t fly exactly the same. They could have probably designed it that way eventually, but it would’ve taken longer and/or cost more. Neither was acceptable.
However, making the plane fly different was also not acceptable. The airlines didn’t want to have to train their 737NG pilots like it was another plane, they wanted minor changes only.
So instead automation was introduced to make it fly the same (or almost) so the airlines could save time and money on training. We don’t want them off in training, we want them flying! We don’t want to pay for that extra training both coming and going!
The problem is, naturally, pilots are not engineers and engineers are not pilots. Both make assumptions the other does not. The engineer that assumed a single AOA sensor was good enough was crazy. Then you had the marketing guys saying that critical flight indicators that could assist the pilots in diagnosing a serious issue should be an add-on for just a few hundred thousand more, per plane! For a light! Guess what? Management says no thanks, our fleet of a hundred would cost too much, we don’t need that.
Why were the pilots not informed? Was that marketing? Management? Airline management? Who knows. But they weren’t because everyone who did know assumed it was a nonissue.
Then the airlines where the pilots and maintainers get less training because of the costs naturally ran into it first. I’m sure if they hadn’t grounded them at some point pilots in the better funded airlines would’ve run into it as well.
After both Boeing and the airlines were so concerned over saving money, both have now lost money, some more than others. Textbook example of penny wise, pound foolish.
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I think this is a bit simplistic. Yes, Boeing obviously assumed that pilots would just treat this as a runaway trim situation, which is a pretty benign affair, and follow their training / checklists to sort the problem. However I think it has become increasingly clear that this was a mistake, and they failed to account for MCAS being more powerful and the failure not presenting itself in the same way, making correctly reacting to the problem more difficult. There was also no slack in the system to allow for human factors.
Training and maintenance are of course pertinent issues, but given that the pilots and airlines were not made aware of the existence of MCAS and that even the best quality parts can fail it seems to me that even those airlines with the best training / maintenance programmes were at risk.
As for the automation vs human debate, this is less clear cut. An objective assessment would lead to the conclusion that you should put the most reliable system in charge, as this would result in the fewest accidents. Historically, this has been a well trained human, as they have generally coped better in an environment that throws up unknown errors that need to be troubleshot (troubleshooted?) and reacted to.
However, we are now living in an age where technological solutions can be created that react more quickly and with better insight than even the best trained human (as an example look at Google’s Alpha Zero AI, which taught itself chess from first principles in only 4 hours, and is unbeatable by any human player). Airbus have demonstrated that it is possible to design a safe and reliable automated system (on par with boeing), and most of their automation is based on 1990’s technology. They are not without their own design issues too, though.
It therefore comes down to three questions:
- Can you supply enough sufficiently well trained humans to meet demand?
- Can you put sufficient care and attention into the design and testing of automation to ensure it performs better and more safely then a human?
- Can the passengers you are transporting psychologically accept that they are travelling in an automated craft and that the computers are in charge?
In my mind I have no doubt that it is possible to design and build a completely automated system that is safer and better than one flown by a well trained human. It is unlikely to be done though because of the effort required for design / testing, and (at least for the foreseeable future) because of the answer to question 3 above.
As always, I am no expert and may well be completely off base with all of this.
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I still think that the worst part of it was that the plane got certified. Still mind boggling to me.
I wrote what I hope might be a helpful parable…
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My question…coming from a mind of a simple pilot…why didn’t they trim the forces out? The trim system worked just fine. It even disabled MCAS for 5 seconds.
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That’s exactly what they tried to do. But in hindsight that was the wrong response. The correct response would have been to treat it as a “Runaway Trim” (which it was not) and lift the cutouts. After that, they could trim manually with the wheels. The motor which MCAS utilized was very fast. So it only took a few seconds before the stick forces were beyond the ability of the yoke to track the nose back away from the drink. Try to imagine a cycle where you get things under control for a moment. You relax a moment then the plane starts trimming wildly again and you once more find yourself along for the ride. Totally terrifying.
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I’ve hear opposite. MCAS is slower than normal trim. …
It is now.
Pilots both real and virtual for whom airliners are pretty dull machines have a backwards concept of elevator and trim. Most planes smaller than a midsized corporate jet have elevators that are big and trim tabs that are small. Airliners have movable stabilizers which are huge and elevators which are comparatively tiny. It is those big stabilizers which are moved by the trim. When you move the yoke you are manipulating the the elevator, the minor of the two pitch controls. If you watch an airline pilot land her jet in gusty conditions you might be surprised at how much yoke displacement is required. At low speed, it takes a lot. This makes for excellent controllability through a huge speed and CG envelope. But it also means that any automated system that is given access to the trim had better be very limited in its authority.
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Now? Boeing updated MCAS logic after crashes and went through red/black label and FAA approval before fleet got grounded?
I am not sure what that means. But I have read that of the many changes to MCAS, one was to lower the trim rate, the other was to limit the length of each application.
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