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Europe says 737 Max won't fly until it completes it own design review

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Re: Europe says 737 Max won't fly until it completes it own design review

#391

Post by foldr »

linuxftw wrote: post #294
foldr wrote: post #281

Earlier quoted context omitted.

I mean, sure, there might turn out to be safety issues that we don't yet know about. You could say that about any plane. >The real purpose of MCAS might be to make an otherwise wildly-unsafe plane flyable MCAS would never activate in a typical flight, so I don't think it can be that bad. There's a simple and plausible explanation for why MCAS was added (the desire to maintain the same type rating). That explanation d…

> MCAS would never activate in a typical flight, so I don't think it can be that bad. Also untrue. There have been plenty of flights where MCAS has activated (either American or Southwest released some data about the number of MCAS activations they had without crash incident). We (the public) don't have any data regarding a flight where MCAS would-have activated but was disabled. In the cases where we know MCAS was d…

I think you're in conspiracy mode on this one. Boeing has shown incompetence and stupidity, and there's a good chance that someone should be held criminally liable. But I see no reason to doubt what Boeing says about why MCAS was added. What would lead me to doubt it is a more plausible alternative hypothesis, which you haven't provided.

> There have been plenty of flights where MCAS has activated

I'm sure there have, but as I said, it would not activate at all on a typical flight.

Re: Europe says 737 Max won't fly until it completes it own design review

#392

Post by ubermonkey »

magduf wrote: post #169
ubermonkey wrote: post #109

Earlier quoted context omitted.

I think you're absolutely right. The approach on the MAX is horrifying. But airplane tech moves kind of slowly, no? Non-MAX 737s can't really change, and so are as safe today as they were 6 month or 6 years ago. The MAX debacle makes me SUPER SUPER leery of any new airframe, though.

The non-MAX 737s are still shitty planes to fly on. It's an ancient airframe: it's cramped, it's noisy, it just sucks. And it's a fuel hog too (which is why they made the MAX version). The competing aircraft are all much newer and nicer. The only reason anyone was buying the MAX was 1) because they had already bought into Boeing and the 737 and it's cheaper to just get a 737MAX which doesn't require any pilot retrain…

But they're SAFE and reliable. Their track record in the air is pretty amazing.

Re: Europe says 737 Max won't fly until it completes it own design review

#393

Post by oreo83 »

kalleboo wrote: post #375
oreo83 wrote: post #356

Earlier quoted context omitted.

Southwest only has 34 737MAX planes in their fleet of 750 737s. "crappy old airframe" It's actually an incredible good design with a proven history. What exactly makes you think its such a "crappy" design?

It's a crappy old airframe because it's designed specifically to be low down to accommodate airstairs, meaning it won't fit modern large engines. It's anachronistic design and has to make tradeoffs in order to stay relevant (even before the MAX, the NG had those weird squished engine nacelles).

Doesn't mean it a bad airframe...

Re: Europe says 737 Max won't fly until it completes it own design review

#394

Post by rbanffy »

gsnedders wrote: post #228
rbanffy wrote: post #224

Earlier quoted context omitted.

> vertical stabilizer was stressed beyond its certified load limits by the pilot's rudder movements. That's something you don't expect to be possible on an Airbus.

Why not? The Airbus A300 has fully mechanical linkage, and none of the fly-by-wire systems introduced later.

Precisely because Airbus was an early adopter of fly-by-wire systems and envelope protections.

Re: Europe says 737 Max won't fly until it completes it own design review

#395

Post by magduf »

vkou wrote: post #345
snarf21 wrote: post #322

Earlier quoted context omitted.

I agree but isn't there enough evidence now for Southwest to sue Boeing to make them pay for all the training (after there is a real fix)?

Generally speaking: 1. These kinds of contracts don't come with provisions for compensation for every foreseeable contingency. 2. You can sue anyone for anything in America. But it's going to cost you. 3. You can also make future purchases conditional on how these contingencies were handled in the past. So, it's likely that a lot of negotiation between Southwest and Boeing will happen. Possibly even some arbitration.…

Well I'm hoping it'll go to massive litigation between many different parties and Boeing, and Boeing goes bankrupt. They can't be trusted ever again.

Re: Europe says 737 Max won't fly until it completes it own design review

#396

Post by magduf »

oreo83 wrote: post #393
kalleboo wrote: post #375

Earlier quoted context omitted.

It's a crappy old airframe because it's designed specifically to be low down to accommodate airstairs, meaning it won't fit modern large engines. It's anachronistic design and has to make tradeoffs in order to stay relevant (even before the MAX, the NG had those weird squished engine nacelles).

Doesn't mean it a bad airframe...

If you have to do crazy workarounds to make a design stay relevant and usable in modern times, then it is by definition a bad design.

Re: Europe says 737 Max won't fly until it completes it own design review

#397

Post by magduf »

tssva wrote: post #178
magduf wrote: post #171

Earlier quoted context omitted.

I have no doubt the older 737s are safe, but they're still crappy planes to fly on as a passenger. Given similar cost, I'll pick an Airbus instead. It's like taking a road trip in a 1967 Mustang vs. and car from 2015. Even if you don't have any incidents, the 1967 car is going to be a pretty lousy experience as far as passenger comfort, noise, and ride quality.

I ridden on some pretty uncomfortable Airbus planes. Passenger comfort has more to do with airline choices regarding types and number of seats than model of aircraft.

Competing Airbus planes have more width, which means the seats can be physically larger. Choosing different seats isn't possible in the 737: the fuselage width is fixed. The only thing they could do to get around this is go to a 2+3 layout, and they're not going to do that because the whole reason for buying and using this plane is economy.

Re: Europe says 737 Max won't fly until it completes it own design review

#398

Post by salawat »

foldr wrote: post #391
linuxftw wrote: post #294

Earlier quoted context omitted.

> MCAS would never activate in a typical flight, so I don't think it can be that bad. Also untrue. There have been plenty of flights where MCAS has activated (either American or Southwest released some data about the number of MCAS activations they had without crash incident). We (the public) don't have any data regarding a flight where MCAS would-have activated but was disabled. In the cases where we know MCAS was d…

I think you're in conspiracy mode on this one. Boeing has shown incompetence and stupidity, and there's a good chance that someone should be held criminally liable. But I see no reason to doubt what Boeing says about why MCAS was added. What would lead me to doubt it is a more plausible alternative hypothesis, which you haven't provided. > There have been plenty of flights where MCAS has activated I'm sure there have…

It has though. There have been several articles about reports filed by pilot's where uncommanded nose down occurred, that the root cause was not ascertained for. This is reported at a minimum here.

https://theatlantic.com/article/584791/

These are by definition "typical flights" until the anomaly occurs.

Also, keep in mind, AoA sensors have long been a luxury for pilots, since they tend to learn the envelope in terms of glide slope, and they are trained to be able to safely operate aircraft without it.

The MAX took a historically non-critical component, and added it to a safety critical process.

I understand that with the sheer number of different points in the timeline of the design, deployment, and operation of these craft, that trying to hold all the context in your head at the same time does make it feel like

"Damnit Jim, we've entered crackpot territory!"

Nevertheless, we have to remain vigilant and open to the fact that malfeasance does happen, and those that would commit it also go out of their way to make it as hard to bring into the open (if intentional), or frequently disincentivize any activity that could potentially make the issue easier to observe since the path of least resistance typically by definition involves minimizing points of inspection or other forms of scrutiny (if the malfeasance is merely the result unintentional misguidedness/incompetence).

Re: Europe says 737 Max won't fly until it completes it own design review

#399

Post by CydeWeys »

dotancohen wrote: post #386
CydeWeys wrote: post #304

Earlier quoted context omitted.

The risk would surely increase with doubled speed, no? The Concorde was unsafe because of all the design constraints imposed by being able to go that fast.

Why do you think that the concode was unsafe? It had a single crash in over 25-years of operation, and that crash was due to runway FOD. That makes it probably the single safest passenger aircraft ever brought to service. In fact, it is probably one of the single safest forms of transportation ever. The concord was involved in single accident resulting in death or injury, which was not due to a fault of its own.

> That makes it probably the single safest passenger aircraft ever brought to service. In fact, it is probably one of the single safest forms of transportation ever.

No, the Concorde was actually one of the least safest passenger aircraft in history, the least safest one on this list by a wide margin: http://www.airsafe.com/events/models/rate_mod.htm

It had so few flights, yet one of them was a catastrophic loss that killed all on board. Just compare it with, e.g., the Boeing 747-400: the Concorde had one full loss in 90,000 flights. The 747-400 has had 0.5 full loss equivalents in 8,420,000 flights. The stats for many other planes are similar.

The Concorde really was quite dangerous. And you can't blame it as "no fault of its own"; it suffered tire blowouts at a rate 30X of other planes, which had previously caused punctured fuel tanks. A tire blowout caused the fatal crash.

Re: Europe says 737 Max won't fly until it completes it own design review

#400

Post by oreo83 »

magduf wrote: post #396
oreo83 wrote: post #393

Earlier quoted context omitted.

Doesn't mean it a bad airframe...

If you have to do crazy workarounds to make a design stay relevant and usable in modern times, then it is by definition a bad design.

The crazy workarounds are maybe bad designs, but an airframe design that's still in demand after 50 years and been built 10,000+ times isn't a crappy design.

I think you'd be hard pressed to find anyone familiar with aviation agree that the 737 is a poorly designed airframe...

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