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Comment by erentz | Hacker News Reader

> What is the endgame now for 737 MAX planes?

The bugs will be addressed and they'll still fly. Airlines have no choice, there's a limited capacity in the world for airplane construction, several thousands of orders on the books for the 737 and 320 waiting to be filled. What can an airline do? They can cut back some orders but not all orders.

> I'd honestly like to see the 737 MAX taken out of service and Boeing simply ending this line.

I have an alternate history fantasy where instead of going with the MAX and then trying to kill the C-series as they did, they instead bought into the C-series. Swapping the cockpit for a Boeing cockpit design. Built the -500 stretch of the C-series, and then used the C-series to replace the 737 line in the <165 pax market. And moved ahead on the 797/NMA for which they'd have a shorter version covering the 200-270 pax market as a pure passenger mover as it's proposed.

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I'm not an engineer but what about:

A) Adding two more angle-of-attack sensors so a pilot can be reasonably sure of auto-adjust will work. Retrofitting those would be expensive, of course. B) Put the two buttons back the way they were and add a "light" indicator an angle-of-attack sensor failure. C) More pilot simulator training so pilots know what to expect in the unusual situation that the system fails.

I suspect the answer would be: "Even now we're not willing to bite the bullet and pay all the expenses we were dodging before".

Searching, it seems Southwest already did something like this (after the first crash, in fact). The problem might be that if Boeing does this on their dime then Boeing would be essentially giving every one of their "bargain" customers the features of their "luxury" customers, which I would speculate might be a vastly expensive proposition especially if it sets precedent going forward.

https://theaircurrent.com/aviation-safety/southwest-airlines...

You need three redundant sensors for safety-critical systems, so that if one fails you know which one is failing. Airbus has three AoA sensors (and three of others as well) on their planes for this reason.

And it's worth pointing out that 737s already have two of these sensors, but don't use them both for MCAS (?!?!).

The A350 has 4 AoA sensors: I suspect it is a lesson learned from an A320 that had 2 AoA sensors froze in the same position, outvoting the only AoA sensor that was still working. In other words: failures are not always independent.

Wouldn’t they eventually all freeze at roughly the same position when the AoA doesn’t change for a while? Can’t they be heated?

They are heated now, after the Air France loss. This incident was also the reason for the MCAS system in the first hand: "Don't trust the pilot, regulate it into safety by your own".

Are you referring to AF447? According to the BEA incident report, the AF447 plane was already equipped with heating systems for the pitot probes and AoA sensors.

"1.6.9.1 Probe heating The probes that are installed on the aircraft are heated electrically to remove water by vaporisation when the aeroplane is on the ground and to protect them from icing in flight."

Reference: https://www.bea.aero/docspa/2009/f-cp090601.en/pdf/f-cp09060...

Right, I mixed that up. With AF447 the initial problem was not the AOA but the very common pitot tube icing, which renders the airspeed indicator useless, thus leading to wrong stall warnings.

Even if the pitot tube is heated (mandatory), very often airframe icing leads to a blocked static port, rendering even more indicators useless.

https://en.wikipedia.org/wiki/Pitot-static_system

They definitely are now. If you want to see what they look like, the channel AvE on YouTube tears one down (Search for BOLTR AoA) and discusses the mechanics. You can see what they suspect to be small cables for heating go up into the element.

https://www.youtube.com/watch?v=NhZ0D-JRtz0

The A350 has two types of AoA sensor - vanes and multifunction probes - which should reduce the chance of everything failing together.

I still don't see how a frozen AoA sensor cannot be detected by the reduction in noise or correlation with other sensors (such as gyroscope or accelerometer).

It probably could, but you'd have to code for that, rather than expecting the majority of 3 sensors to always be right.

The trick is to detect conditions like this with virtually zero false positives. Say the sensor fails one in 100,000 times and your algorithm has a 1/100 change of flagging a false positive in the case where the sensor is in fact working properly. Then the chance of a real failure successfully detected is:

    0.00001 * 0.99 = 0.0000099

The chance of a false alarm is:

    0.99999 * 0.01 ~= 0.01

Thus:

    P(failure|alarm) =  P(alarm|failure)*P(failure)
                        ---------------------------
                                P(alarm)

                     =   0.99 * 0.00001
                        ----------------
                        0.0000099 + 0.01

                    ~= 0.001

So alerts from your seemingly ok-ish algorithm will be false alarms 99.9% of the time!

Majority vote is a very simple system to reason about. What you’re describing adds a whole bunch more complexity.

For the noise sensor scenario, is the sensor failing or is the ancillary (and single point of failure) noise sensor failing? What happens when you have a false positive like that and a false negative on another sensor?

For the correlation scenario, when you have two systems that disagree, how do you determine which one is failing? Are their precisions and tolerances sufficiently close that you’ll get a warning at a useful point in time?

Maybe you could have a pair of vanes. Each vane is physically limited to a portion of possible angles. Vane A would only work above say -10 degrees AOA and vane B below +10 degrees AOA. This would give you a regular test of both sensors when the AoA changes in normal flight. You have more bounding of correct values.

It is not certain that the 737 AOA ectually needs to be safety critical. You could just ignore the AOA data completely and divert. The pilot should still have sufficient instruments and training to land safely.

The problem is without MCAS and the AoA sensors that power it the 737MAX8 handles differently enough that it would be categorized as a different aircraft and require recertification of pilots. This happened because the 737 frame is relatively low to the ground and to increase fuel efficiency the only real option is a larger engine so Boeing pushed the engines up and forward. This changes the relation between the Center of Thrust and the Center of Mass on the plane causing it to have a tendency to pitch further up towards a stall when climbing so Boeing added the MCAS to make the new plane behave like the old plane by automatically performing the pitch down maneuver for the pilot.

This system is critical to the Max 8 remaining classified to 'fly the same' as the 50+ year old 737 air frame design so it's critical to pilots being certified to fly the plane at all. Ergo it is a critical system and needs more redundancy or the Max 8 needs to just have a new type certificate and pilots certified to fly it as well.

Boeing REALLY REALLY doesn't want to do this because it would require airlines to retrain their pilots to use it in their fleets making them less attractive to airlines. The whole fiasco is a confluence of 1) Cost of retraining pilots on a new air frame 2) need from airlines for a more efficient plane 3) the old 737 design not having any more room below the wing for a bigger engine (which is pretty much the main way we get more efficiency these days).

As long as safety is regarded as a luxury feature, these failures will continue to happen.

It’s very expensive, but not nearly as expensive as losing all their 737 Max orders.

While true I don't think that airlines and regulators will go for it, if there's even the slightest risk of an additional accident. No matter what.

And Boeing's "communcation strategy" after the incidents doesn't really help to instill confidence in the plane.

Conversely I don’t see how they can’t be returned to the sky. Boeing has deep pockets and the US government will push behind the scenes to make sure it happens, regardless of whatever public statements they make. There is no way regulators will be able to keep this plane grounded simply on the ground of politics.

You're saying we literally can't stop our representatives/"regulators" from getting us killed anymore. Lovely.

Both accidents could have been avoided if the pilots knew about the changes in handling and in MCAS and how to handle it. So this is not the kind of flaw that would make a plane uncertifiable or unflyable. Combine that with Boeing’s strong lobbying efforts and importance to the US economy, it is a certainty the planes will fly.

The simple solution would be to just remove MCAS and take the certification as a new plane. Boeing might have to eat the retraining costs but it's got to be better than eating the cost of the planes should they be deemed unfit for purpose and Boeing sued by every airline to recoup the costs of the now useless planes.

There's also the possible hardware fix to add an additional AoA sensor and change the software to limit the total deflection allowed + add a way to disable the MCAS only while keeping the electronic trim. The plane itself isn't irredeemable by a long shot though.

> The bugs will be addressed and they'll still fly.

The engines are mounted incorrectly, so much so that Boeing believed pilots need the assistance of MCAS on take-off now.

The bug isn't with its algorithms, rather the need for MCAS to begin with. They can't "address" it. That's why I'll be very careful not to ever book a flight on a 737 Max, probably easier to simply stick to Airbus-only airlines: Jetblue, Alaska/Virgin, etc.

Alaska is Boeing, Virgin is Airbus, Alaska/Virgin is primarily Boeing...

And Bombardier and Embraer.

Yup:

https://www.vox.com/videos/2019/4/15/18306644/boeing-737-max...

> The engines are mounted incorrectly, so much so that Boeing believed pilots need the assistance of MCAS on take-off now.

This overstates the issue. The engine mounting changes the flight characteristics enough that the MAX 8 needs to be flown differently in certain corners of the flight envelope. The MCAS was added to avoid having to re-train pilots or trigger a new type certification.

The engine mounting certainly does not make the plane unsafe.

Why is this commenter grey in my thread? They are absolutely correct, and anyone who disagrees really needs to say why.

> The engine mounting certainly does not make the plane unsafe.

I don't think this is a very...'precise' statement. what is "safe" in the context of aviation? If you had no MCAS, then this plane has a very bad propensity to stall. I hope we can both agree that's an unsafe airplane. You can't just say "don't do that [pull up too much] and then you're fine". The aircraft "wants" to pitch up too high and stall, which predicated the MCAS system itself. So to me, yeah the engine mounting (in and of itself) makes this plane quite unsafe.

Now, with a properly functioning MCAS it may be "safe", but when the MCAS is itself another point of failure, my opinion is that the aircraft is only safe on paper, while in practice it's just got too many hacks and kludges for it to be practically safe for the millions of safe flight hours that these things are expect to deliver.

No, it did not “have a bad propensity to stall”. That’s a very imprecise statement in the first place but if you take it to mean, it would try to stall during normal flight conditions, it’s definitely false.

Airbus aircraft are “safe” despite the fact that dual conflicting pilot input is averaged without stick feedback (see the Airfrance flight from Brazil). If electronics being used to fly the aircraft upsets you, you’re going to be in for a real shocker on any airbus.

> That’s a very imprecise statement in the first place but if you take it to mean, it would try to stall during normal flight conditions, it’s definitely false.

The precise wording would be that it is dynamically unstable, and the ball is with Boeing now to prove it's not the case. Also after all we discovered on the last weeks, Boeing better make a good case, or they won't convince anyone.

The US aviation industry is about to change. I don't know into what, but it's not in a stable situation.

No, it did not “have a bad propensity to stall”.

Okay, how's: you can use thrust to pitch up a 737 beyond the authority of the elevator.

Airbus aircraft are “safe” despite the fact that dual conflicting pilot input is averaged without stick feedback (see the Airfrance flight from Brazil).

There is an aural warning (DUAL INPUT) on Airbuses with conflicting input.

So much ignorance and misinformation about this issue even on HN.

The parent comment and entire thread is 100% correct. There is nothing inherently unstable or unsafe about the MAX 8. It has a pitch-up characteristic that's mild compared to some other commercial jets like the 757.

The only reason MCAS was put on that plane was to allow the MAX 8 to share a type rating with the rest of the 737 family, to make it so that it handles like any other 737 despite the pitch-up characteristic.

Go ask any commercial pilot, go watch any of the commercial pilots on youtube who have commented on this, go look on stackexchange. The notion that the MAX 8 is inherently unstable, or unsound, or dangerous, is a laughable myth to anyone in the industry. I get that the news cycle is financially rewarded for fearmongering, but I really expected people who frequent HN to know better and do some cursory research into the topic rather than posting comments that perpetuate bullshit.

There are several major issues with what boeing has done, such as the alleged failure to reclassify MCAS as a critical system after flight testing. But instead of discussing these legitimate issues, public debate seems to have been directed towards a bullshit myth about the airframe being inherently unstable. This has been eye-opening and dispelled my notion that HN had above-average quality of discussion on technical topics.

you're concerned about "comments that perpetuate bullshit". To me, the real bullshit is that a computer drove 2 aircraft into the earth. If we're so mistaken about what happened here, maybe the boeing engineers are similarly mistaken about how flight control systems work. I think they're the ones who have "ignorance and misinformation", like how many AoA sensors are required. Or whether a vigorous elevator UP position from the stick should be ignored and in fact counteracted by an opposite stabilizer position. Tell me what perpetuates the arrogance in the software departments at boeing that the computer knows better than the human. Unlike the pilots, the computer has nothing to lose. Yet the computer won the final decision. But calling this out is just the "news cycle financially rewarding" ... something ?

It has a pitch-up characteristic that's mild compared to some other commercial jets like the 757.

Do you have any personal experience with or references for this claim?

That's not quite correct. When the aerodynamics of a plane was not designed to push forward the mounting of the engines, you have more reinforcement. That alone causes an uneven distribution for lift not accounted in the design itself. THIS is what causes the plane to nose up. But that doesn't mean stress is not put on the frame itself and mechanical parts that will be, on a daily basis, "abused" to the point of metal fatigue. You see, when it comes to aerodynamics, it's easy to test it on a simulator. And it seems boeing's 737 max passed with flying colors. Then, it had to fly. That's the moment when test pilots came to a conclusion that the design will not work. Boeing's solution was a software "fix" and it needed to relay on 1 sensor to pass certification.

So, what do you have? NO TRAINING on this airplane, a bugged software system, poor aerodynamics, poor design choice, stress on elevator, etc. The ethiopian airlines plane had such force that pilots were not able to manually turn the trim control wheel. Do you know how much force that plane had to have that the jack screw couldn't be operated manually? THAT is a severe design flaw. THAT is what is being investigated. Who is investigating Boeing? Boeing is investigating Boeing. Boeing on 5/7/19 admits it knew they had a severe problem but it can still be fixed. Who certified the fix? Boeing. But now the FAA is investigating that fix which was promised by April. Again, this is a severe design flaw with still many unknowns yet to be found.

Nobody who isn't an engineer wants is terribly interested in the argument that a model of plane that has killed 2 planes full of people recently is in anyone's opinion safe.

Personally I won't fly on one in my lifetime.

I'll leave the analysis of why to others to figure out why I fly on other airplanes.

Incidentally I have seen pilots argue that the max is inherently unsafe on this forum which is probably why people are reiterating it.

What is your area of expertise and what is your opinion?

Actual engineers do care about the "why" since that's what matters. Otherwise don't bother flying on any aircraft since all models have crashed at some point.

Your second sentence is too glib. By just about any statistic you want to look at, the MAX-8 has an abysmal safety record. Probably worse than any other aircraft in revenue flight.

It's perfectly rational to look at the results, regardless of "why", and decide that the risk is just too great.

You're missing the point of the post you're responding to. The poster is saying that the 737 MAX isn't inherently unsafe due to its aerodynamic configuration. The safety issue arose from the bungled MCAS system. This could be fixed without changing the airframe.

The 737-MAX with the larger engines turned the statically stable airframe into one that must use computers (eg MCAS) to make it dynamically stable which is a technique used on modern fighter jets but to my knowledge has never been applied to a passenger aircraft.

In this plane which is not "fly-by-wire" the pilots are part of the safety loop and are given a certain short amount of time to respond to an emergency.

Troubling to me is the footnote in the manual which there are times where the manual wheels for the trim require 80 lbs or 100 lbs or more of force. This amount of force would potentially preclude female pilots on these planes to handle these sorts of emergencies.

>The 737-MAX with the larger engines turned the statically stable airframe into one that must use computers (eg MCAS) to make it dynamically stable which is a technique used on modern fighter jets but to my knowledge has never been applied to a passenger aircraft.

This is completely false. The 737 MAX does not have relaxed static stability in the manner of a fighter jet. It just has different handling characteristics than earlier 737s at high angles of attack -- a region of the flight envelope that the pilot should never take the plane into in the first place.

Fighter jets of the kind you're referring to require continuous and precise adjustments of the flight control surfaces merely to avoid departing from controlled flight. This is absolutely not the case for the 737 MAX.

The aircraft flies fine. MCAS is a stability control system that applies in certain cases (full power, high angle of attack) where the nose pitches up. It may lead to a stall but that's not what it's correcting for and it doesn't just happen during level flight. If the MCAS system was disabled then pilots handle it manually. Trim is not an exotic concept and just takes training and understanding of the operating characteristics.

Airliners are very safe. They're not in dynamic stability like jet fighters and don't need active measures at all times to stay airborne. Having sensors and systems that coordinate to keep the aircraft flying optimally to remove pilot load and increase safety margins is a good thing and has been in use for decades.

The problem here was a badly implemented system without redundancies and without enough training so that pilots were actually aware of the flight profile and MCAS. Also aircraft do not have millions of flight hours, they wouldn't reach a million even if they flew 24 hours a day for 100 years.

The aircraft flies fine in most flight profiles, yes.

At high angle of attack, the MAX-8 is more unstable than pilots were trained to expect. And the MCAS has done an absolutely miserable job of fixing this. Worst case scenario bad: it caused the loss of two airplanes that, if the MCAS had never been added to the MAX-8, would have reached their destinations just fine.

Until the it flies predictably in every flight profile (including high AOA), it's demonstrably wrong to say "the aircraft flies fine." Maybe it will eventually "fly fine" but Boeing's got quite a bit of work to do first.

Alternatively just train the pilots on the behavior in the domain where MCAS would activate. MCAS main purpose is to lower the training requirements.

Not quite if I am to believe other HN comments. The thing MCAS compensates for is that, in certain cases, as you pitch up more, the pressure on the stick decreases. This feels to pilots like leveling out, which is dangerous. MCAS was designed to counter this.

The specific design of MCAS and not adding any new procedures, was to lower the training requirements. Specifically, anyone certified on the old 737 was still certified on the max.

If they had improved the interface of MCAS and changed the procedure for runaway trim, it would have required more training. However, without MCAS or another remedy for the 'decreasing stick pressure at increasing pitch' problem, the plane would not have been allowed to fly at all.

> This feels to pilots like leveling out, which is dangerous. MCAS was designed to counter this.

Pilots are trained extensively not to trust what motion feels like, and to use the horizon and instruments. An adjustment in stick pressure is not a notable new threat, they just need to be trained for the plane's behavior.

That’s the whole point: the MCAS was supposed to be cheaper/easier for the airlines than new training.

You wouldn’t be retrained to ignore cues from your senses and trust your instruments. That training happens when you’re young and getting your IFR ticket.

I'm just pointing out that "they just need to be trained for the plane's behavior" isn't on the table for the MAX-8. The contracts said it would have the same type rating, and therefore the MCAS, for better or for worse.

I'm not quite sure how that is related to beginner flight lessons. (?)

> An adjustment in stick pressure is not a notable new threat, they just need to be trained for the plane's behavior.

It seems that what you claim is "not a new threat" is actually forbidden by the regulations, because it was recognized to be a threat.

To clarify, since this seems to be a slight misreading of one of my comments.

The original one is https://news.ycombinator.com/item?id=19568158

and was written at night, so there's some loopy phrasing in there I never corrected. Let me unpack some of it to fit the context here.

The pressure applied on the stick itself does not change. Rather, the function of how much deflection you get out of the plane per unit force applied to the stick changes.

Design regulations state an airframe for which this curve at any point goes negative cannot be certified as a civil transport airplane.

That means, there should be no point in the flight envelope where the sensitivity of the controls drastically changes. It should be a predictable increase in force required to get more deflection, all the way to stall.

With the MAX without MCAS, this rule is broken at high AoA when the engine nacelles start making lift.

MCAS is meant to compensate for this necessary breakage by inducing some mistrim.

The effect of mistrim in that case is to cause the controls to require more force to induce those last few degrees of deflection, using the AoA sensor as the primary indicator as to whether the system should activate, in order to bring the curve into compliance.

The problem, as hinted by the response to my post in that thread, is that an honest to god stick-pusher would be more akin to the system you'd want for that. Adding the AoA sensor as a single point of failure is insane, due to the consequences should that sensor start spewing garbage data in normal flight.

Most of those are realizations I came to after stumbling across a Royal Aeronautics Society interview of D.P. Davies, a British test pilot for the ARB, the aircraft certification authority for the U.K., which I believe I linked in the comment.

At the time I wrote it I was in the midst of a deep dive into the more arcane aspects of control systems. I have some literature tucked away somewhere that I was referencing, bit I'd need to dig rather deep in my browsing history to recover all the context.

An interesting historical note: MCAS is similar to a system McDonnell Douglas implemented in MD-11's (LSAS, Longitudinal Stability Augmentation System) for the same reasons as Boeing eventually implemented MCAS: to be able to claim that the new aircraft flew just like the old MD-10.

Makes one wonder if someone brushed the dust off something that really shouldn't have been emulated again after the merger.

There are already lot of things that pilots have to keep in mind and look after. Learning how MCAS changes the behaviour of the plane makes everything more complicated.

To me MCAS looks like an ugly software hack implemented to save money on redesigning a plane and re-training pilots. It brings several problems:

- it is difficult for pilots to understand how MCAS works, and how to diagnose failures. They are not programmers or engineers. And MCAS doesn't provide any debugging information about its work anyway. And pilots don't have time to analyze it.

- it adds new points of failure

- sometimes there are situations when automatic systems shut down and pilots have to control everything manually. With MCAS, they would have more things to look after. Pilots who got used to flying with autopilot are usually not comfortable with manual flight, and systems like MCAS only make things more complicated for them. An example is a recent crash of SSJ100 in Moscow where experienced pilots failed to land a plane manually after autopilot has turned off.

So I think that plane designers should be very careful with adding more automatic controls. Especially if their purpose is only to save money at cost of making place less safer.

Yes, that's what I said. The artificial behavior would be fine if the pilots actually knew it was artificial and how it was being done. That lack of understanding and training is the critical error, made worse by a poorly designed system that failed too easily.

> The artificial behavior would be fine if the pilots actually knew it was artificial and how it was being done.

If I remember correctly, the behavior you promote as "fine" is forbidden by the regulators, and not accidentally.

If it’s prohibited then how was it certified?

> If it’s prohibited then how was it certified?

Without the active MCAS the plane would have not been certified because the behavior of controls is then not inside of the prescribed limits.

I was talking about the the artificial behavior, so if it was certified then it was deemed allowable to have a stability control system maintain the necessary behavior.

If the plane must have natural behavior, then MCAS would not allow it to be certified because it's artificial control.

Then I misunderstood your point, sorry.

> Also aircraft do not have millions of flight hours, they wouldn't reach a million even if they flew 24 hours a day for 100 years.

Most commercial planrs fly 3000 hours a year. There are about 400 787-Max planes built - that's a million flight hours per year already (if they weren't grounded...)

The engine mounting certainly does not make the plane unsafe.

The engine position exacerbates a problem already plaguing the 737 since the Classic. I think you're understating the problem quite a bit here.

> The engine mounting certainly does not make the plane unsafe.

Unless there is something about the magnitude of MCAS necessity that Boeing did not tell us yet.

Boeing's original stance of "stupid pilots should have followed runaway trim procedures" does not seem very consistent with actively removing a two-stage disable feature that already existed (and which, in hindsight, might have saved those lives). How desperate exactly were they to never ever let the pilots catch a glimpse off the real flight characteristics?

Alaska was, before they bought Virgin, famously a Boeing-only airline! (And a 737-only airline at that!)

I was gonna say... How could a Seattle-based airline be all Airbus?

Yet Horizon Air currently operates two types of aircraft, the Bombardier Dash 8 Q400 turboprop and the Embraer 175 regional jet. They’re a 100% subsidiary of Alaska Air Group and Alaska Air puts its code on them.

Did they change to require MCAS on take-off? Last I heard, MCAS was disabled at an altitude before 400 feet

MCAS isn't even active during take-off: as long as the flaps are extended, it does not activate.

> Airlines have no choice

Anecdotal: I know of at least one family that booked a trip on a non-Boeing airline, at additional cost, to avoid risking being on a Max.

Imagine that after the Max is back in service, that there is a serious incident in the first few months - it doesn't have to be fatal, just a close call of some kind - how many more customers will avoid the Max at all costs?

How do you know the plane model before you board? It's not shown when buying the ticket, it's not written on the ticket either.

Some airlines do! Qatar and Emirates, I think.

but they rotate them quite a lot, don’t they?

i booked a boeing 787 dreamliner but ended up in a crummy 777 from a decade ago.

It should be there among the flight itinerary data, often hidden behind an accordion or tooltip.

Delta showed me when buying online. Let me select seats too.

You can avoid airlines that have the 737 MAX in their fleet (domestically, the biggest are United, Southwest and American). Whenever I fly I fly Delta, and I’ll never fly on a MAX because Delta doesn’t have any.

You can find that at https://flightaware.com just from the flight number...

Count one more please. Searched for flight, saw Boing 737, no thank you! Paid premium for Airbus. That’s for three passengers.

You know the 737 and the 737 MAX are two completely different planes right?

I'm not going to fly on any 737, just in case the MAX bit gets truncated. Everyone I've talked to has expressed the same fear. I don't care if it's irrational or not - it's my life, and I'm not risking it on one of these stupid, cost-cutting planes.

Boeing 737-MAX is longer than previous iterations of 737.

And that means...?

You cannot confuse them because of the sheer size and shape difference.

The physical characteristics are not presented to you when booking your flight.

By the time you've arrived at the airport and see the MAX at your gate, it's too late and you've already paid your fare.

You can DDG specifications of your plane by model number and nay, they have to be unique per revision.

I'm choosing

1. to make certain I don't board one of these machines by mistake. I will not risk my life over this egregious comedy.

2. to vote with my dollars and punish Boeing and businesses that do business with Boeing, especially if they refuse to remove these planes from their fleet.

What Boeing committed here is leagues beyond the recent emissions scandals. It's criminal and the perpetrators should be afraid of the coming justice. This should honestly be as close to a company-ending event as one could imagine. We shouldn't treat this lightly, slap on the wrist, business as usual. This must never happen again.

Yes I do. But as the comment above says, I am not risking it, even though it is borderline irrational.

> Airlines have no choice, there's a limited capacity in the world for airplane construction, several thousands of orders on the books for the 737 and 320 waiting to be filled. What can an airline do? They can cut back some orders but not all orders.

In a world that had actually severe consequences for corporate negligence, regulators would force Boeing to let airlines cancel/change all orders, and compensate them for the 737 Max models they already shipped to them, as they cannot be flown safely. Boeing's behavior does not indicate that they are interested in properly fixing this problem as opposed to getting it certified via corporatism / the FAA allowing them to perform a big part of their own checks.

They won't fly if customers won't fly on them. The first part of the rehab will be renaming and rebranding the product to reduce customer stigma.

> Airlines have no choice, there's a limited capacity in the world for airplane construction,

No choice? It's a choice between risking passengers' lives and money. Be real about what the choice is.

If we're being real about the choice, then you also have to include the reality that many airlines would go under if they suddenly had to retire their MAX 8 fleet and weren't immediately able to replace them with other aircraft. A great many more people would have their lives severely impacted by the closure of a major airline than by a plane crash.

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