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Comment by tuna-piano | Hacker News Reader

737Max is certainly tainted now. But will that last forever? And do non-HN-aviation-geek consumers really care enough to check the model of the plane they'll be flying on, let alone make a flight decision based on the model?

Certainly another crash could be devastating to the model.

But was the 737Max a poorly designed death trap rushed to production or a super safe airplane with a single fatal flaw?

Time will tell...

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Certianlly not just a single flaw. They found and fixed multiple other flaws while checking though everything for re-certification.

In my opinion, the 737Max is probably one of the safest planes right now, simply because of the amount of scrutiny it's been though.

Unless, of course, it was fixed and scrutinised by organisations which still have the same systemic flaws as the first time around.

Until the sociotechnical systems that do the work change, they will keep overlooking problems and making similar mistakes, from a high-level perspective.

Do you mean the same regulatory organizations that have reduced the US airline fatality rate by 50x over the last 50 years to the point where it's now over 100x safer per mile to fly than to drive?

I mean the FAA certainly has some flaws, but it's important to keep things in perspective.

Don't get me wrong. If I'm going to trust anyone to learn from their mistakes, passenger aviation are the ones.

I'm just saying that when it comes to complex systems, it's not evident that someone who said "I've looked at it and it checks out", the thing fails, and then the same someone said, "Okay, now I've really looked at it and it checks out again" that it's now safe. There's more nuance to it than that.

Whether or not that nuance has been taken in consideration by the FAA this time I really am not in a position to say.

A caveat here is that the modern FAA is very different than the FAA of even 20 years ago. In response to decades of stagnant funding, 'the beast' is fundamentally unable to fill the same regulatory role it was intended to do - to all of our detriment [0].

[0] https://www.washingtonpost.com/investigations/how-the-faa-al...

I think the passenger miles statistic is baloney (calculated by multiplying the number of passengers by the number of miles travelled), and I'm a bit sick of seeing it trumpeted everywhere to claim flying is vastly safer than driving. The collective risk of everyone on board the plane is meaningless to calculating risk to your personal safety. At least for me, the fatality rate per journey, per hour of travel, or at the very least per mile I myself am travelling, is far more relevant. According to one source, flying is actually three times deadlier per journey than driving (fun fact, this is the metric aviation industry insurance companies use), but about four times safer per hour travelled. So flying certainly can be safer than driving in the right context, but these crazy "100x safer than driving" stats are kinda useless and take a lot of "creativity" for airlines to arrive at.

source: https://en.wikipedia.org/wiki/Aviation_safety#Transport_comp..., citing Beck, L. F.; Dellinger, A. M.; O'neil, M. E. (2007). "Motor vehicle crash injury rates by mode of travel, United States: using exposure-based methods to quantify differences"

Why would you care about per-journey statistics? Surely all that's demonstrating is that cars are often used for very brief, non-highway travel.

When the question is of how to travel between cities or states, why do you find the relative safety of low speed non-highway driving to be relevant?

Maybe because the choice I make as a consumer isn't between going to Hawaii by flight or by car -- it's whether to make a plane journey to Hawaii or a car journey upstate.

So maybe per total hour from door to door is the relevant metric: you tend to make decisions based on comparable travel times, whatever the reason for travel or mode eventually selected.

> Do you mean the same regulatory organizations that have reduced the US airline fatality rate by 50x over the last 50 years to the point where it's now over 100x safer per mile to fly than to drive?

As a layman, per-mile normalizing of the safety statistics feels wrong to me, given the speed and distance disparities between car and air travel (for many trips, the two modes aren't really substitutes).

IOW, 100x safer per mile doesn't look as good when contemplating a plane trip 200x longer than your daily commute.

I'm not sure what would be best, but either time-based or per-flight normalization seem like they would be an improvement. Or perhaps per-person (eg. x people fly per year, y have been in an accident).

I mean it still only adheres to safety standards of the 70's by using a loophole in the regulations...

Well the engine placement hasn't been changed and that was the underlying problem that lead to everything else.

To be a bit more nuanced, it's not that the engine placement was the problem, rather it was that Boeing made software adjustments to make the plane fly like a regular 737 without training the pilots in these changes.

The engine is the start of the problems

The fundamental problem is a lack of effective redundancy for bad sensors. They haven't fixed that. Software alone will not fix it. They've just implemented superficial procedures that don't address the real safety issue.

> rather it was that Boeing made software adjustments to make the plane fly like a regular 737 without training the pilots in these changes

No, this is a persistent and pernicious myth on HN – that the MCAS was some sort of “737 Emulator” intended to allow the plane’s customers to avoid pilot training.

In reality, during testing it was discovered that the engines’ new position caused the stick forces to invert in some situations during flight. “The stick forces invert” means that it becomes easier to pull into an aerodynamic stall than push away from it.

This fails a Fundamental Airworthiness Requirement that all commercial aircraft are required to conform with for certification.

Boeing’s “solution” was MCAS – using the stabilizer trim to automatically push the plane’s nose down as it approaches a stall (and therefore putting additional force on the stick that keeps it at all times easier to push away from the stall than pull into it).

The pilot training thing was just that they concealed the existence of MCAS from pilots out of fear that it would prompt calls for additional training.

tl;dr the problem was that the engine aerodynamics made the plane fundamentally uncertifiable without a software hack.

Boeing whistle-blower says proposed 737 Max fixes aren't enough.

179 points by bookofjoe 50 days ago

https://news.ycombinator.com/item?id=24543411

It is methodologically unsound. The airframe is unstable. The fixes are software and training, human factors engineering, and hence don't address the underlying problem which is one of physics. I am sure that the measures taken will reduce the rate of crashes, but doubt that they will eliminate them, as you can't exclude effects without first excluding causes.

In my experience the non aviation geeks are also worried about 737 Max’s.

That’s validated by the fact that the involved companies are referring to it as the 737-8 instead, which will not fool anyone who knows anything about aviation and is geared entirely towards ordinary people.

There's already the 737-800. So you're saying companies flying the Max may have in their fleet both a 737-800 (aka the "738"), and what they're now calling a "737-8"?

I do remember the flight app I used to use show me the aircraft make and model and even serial number. Hopefully they keep doing that.

Referring to it as the 737-8 is consistent with their current branding lineup. See other numerous examples 747-8, 787-9 or 777-9.

Similarly the 737-800 is widely just referred to as the 737-800 and not the 737 Next Generation 800.

I always check that and choose carrier that uses plane I like.

Not an aviation geek. You'd be surprised how nitpicky people will get when it comes to their family's safety. Between when the MAX problems came out and the fleet was grounded, I cancelled my family's vacation at substantial cost and inconvenience because the airline had 737Maxes in the fleet and I saw that my flight had been flown by Maxes previously.

This has gone beyond aviation enthusiasts. I think you will find a not insignificant number of regular people who are skittish about flying on a Max.

Would love to know how many more clicks there are on flight details on booking websites once Max returns.

> I think you will find a not insignificant number of regular people who are skittish about flying on a Max.

It won't be listed as one.

https://www.businessinsider.com/boeing-737-max-name-change-r...

DC-10s continued to fly after several notorious crashes. They are still flying today, though not in commercial passenger service.

Another crash will probably mean the end of Boeing as we know it.

How many people actually look at what plane they're meant to get when they compare times, dates and prices for their booking? Let alone what plane is actually at the boarding gate 6 months later...

Before very few. I absolutely would now.

I bet more than a few traders looking for an edge are trying to find someone who works at Kayak to tell them how many more clicks there are in “see full flight details” before purchasing a flight there are now.

Thats great. But then when you get to the gate and there is a 737Max sat there waiting for you, do you board? Or do you accept that you won't get a refund and now need to buy another flight and just hope there is one today for an affordable price with a seat not on a 737Max?

Was thinking similarly. I don't think there's any guarantee you'll get the particular plane model that is scheduled. Maintenance or other factors may mean model X is unavailable, and they substitute model Y instead. You've contracted to get from point A to point B via plane, that's typically it.

Consumers aren't exactly helpless here. The worst-case scenario is the customer is unable to get another flight (for whatever reason) and 'has to' board the 737Max that one time. The customer can then choose not to book with that airline again. I'm already not a fan of AA, and with this news I can happily avoid this situation by simply not flying AA.

Will I always feel this way? We'll see. I'm fine with letting other people be volunteer guinea pigs before I commit to something.

It would be interesting to see how elastic demand is for this factor. I guess it depends on how easy it is to book the same flight with another airline who don't use 737Max vs how much of a discount the airline can get for using them (plus passenger numbers and what proportion care and how effective a rebranding they can run etc).

except at least initial the airlines will probably accommodate the people who don't want to get on the plane because it is a Max. Better a little problem of rebooking, than social media posts that will remind people hey they are forcing you on a death trap.

Whether it is or not, best not bring attention to the fact you might be flying on a Max.

That's fine as long as there is a flight between the same 2 destinations with the same airline in a few hours that doesn't use a 737max.

If not then what?

I can see the 737 being pushed to infrequent routes with minimal competition. If you want to fly from Fairbanks to Springfield, it's the 737 or nothing and you either fly now or wait 4 days for the next flight (or pay 8000usd for a 19h, 4 leg super combo...).

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