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

bloomberg.com

131–140 of 407 posts

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

#131
post #29

Looks like the EASA finally figured out that the FAA can't be trusted with matters regarding Boeing.

A diplomat would say we could trust the FAA but now they need to be verified.

A diplomat would say that while the FAA tests planes to the highest standards, there's no harm in testing to the highest standards twice.

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

#132
post #122
post #64

Earlier quoted context omitted.

This is not the case. The 737 MAX has different handling characteristics to a regular 737, but there is nothing inherently unsafe about those handling characteristics. The purpose of MCAS was just to prevent the need for pilots to recertify by masking the difference.

They lengthened the plane without redesigning the rest of the components to compensate. This changed fundamental aerodynamics on how it flies. The plane is dynamically unstable and that instability was masked in software.

Dynamically unstable means that it will leave controlled flight if it does not receive control input, and that the departure from controlled flight will accelerate after it starts, therefore requiring constant computer-assisted control inputs. Pretty sure this is not the case, but it will have different and potentially dangerous behaviors for some speeds, angles of attack and thrust settings.

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

#133
post #40

Is anyone else extremely reluctant to fly on a Boeing plane after this? A lot of people say "It's no big deal, they just need to update the MCAS software" , but I see this entire situation as a sign of much deeper issues at Boeing, issues that can't be fixed with a simple software update and could affect every plane they make.

> on a Boeing plane

yes but limited to -MAX

the others have a good track record and for some reason they seem to takeoff and land smoother, even if probably it's selection bias due to the high correlation of [airline, plane, destination] variables.

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

#134
post #69
post #40

Is anyone else extremely reluctant to fly on a Boeing plane after this? A lot of people say "It's no big deal, they just need to update the MCAS software" , but I see this entire situation as a sign of much deeper issues at Boeing, issues that can't be fixed with a simple software update and could affect every plane they make.

They've had similar issues before. https://en.wikipedia.org/wiki/Boeing_737_rudder_issues

767 Thrust reverser as well

https://en.wikipedia.org/wiki/Lauda_Air_Flight_004

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

#136
post #63

Earlier quoted context omitted.

The fix for the 787s Lithium battery problems wasn't a whole lot better. Remember those exploding left and right and the 787 fleet grounded? The fix wasn't to reengineer the large amount of electrical systems, lack of bleed air or use of different batteries. The fix was to put them in a stronger container with a hole in it so they can vent outside when they inevitably blow up again. That has worked well. So far. Kind…

That’s horrifying. I’ve also heard that the 787 was a boondoggle.

The 787 is weird (and possibly unsafe) for at least two significant reasons.

Firstly, Boeing totally re-invented their approach to assembling planes. Previously they built most of the aireframe components and assembled them in their own plants. But the 787 was specced out during an ongoing Boeing/Airbus anti-trust dispute over government cross-subsidies that turned nasty (escalated to USA/EU level, mediated via the WTO, with sanctions threatened). For strategic reasons Boeing decided to outsource subassembly production to third parties and retain only overall control and final assembly (the goal was to have 51% of the work go through the EU, so that the EU would shoot themselves in the head if they applied sanctions against Boeing aircraft). (Similarly, Airbus did much the same: you can buy A320s—the 737 series' Airbus rival—built entirely in China, for example.)

Anyway, this resulted in huge cost overruns, delays as small suppliers grappled with trying to supply components of reliable quality and consistency in Boeing-scale quantities, and so on. On the other hand, it gave Boeing a shiny new 21st century supply chain which they're using on new projects, so the $30Bn wasn't entirely wasted on just one bird.

Secondly, Boeing went full-tilt for composites in place of aluminum as the main structural material.

Now, Airbus had been building composite airframes for decades at this point, but they got there incrementally, and not without fatal accidents. See for example the crash of American Airlines flight 587:

https://en.wikipedia.org/wiki/American_Airlines_Flight_587

It turns out that switching to all-composites from aluminum has some serious gotchas, including entirely different wear/fatigue/delamination issues.

Boeing has done surprisingly well up to this point with the 787 (although the early Ethiopian Airlines hull loss ground-side due to a runaway battery fire should be a warning—it was a shiny new plane and the battery fire burned through the top of the hull, turning it into a $200M write-off; an aluminum bird could probably have been patched and repaired). But we have no idea whether Boeing managed to avoid baked-in long term weaknesses in the airframe, of the kind that only show up 10-30 years into an aircraft's life. Such weaknesses can show up suddenly and kill an entire type within a matter of months (see for example the fate of the Vickers Valiant, a British strategic bomber of the 1950s that succumbed to cracked wing spars and was hastily scrapped).

Anyway: this is why I'm very dubious about flying on 787s, at least for another few years. Your mileage may vary, obviously ...

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

#137
post #65
post #40

Is anyone else extremely reluctant to fly on a Boeing plane after this? A lot of people say "It's no big deal, they just need to update the MCAS software" , but I see this entire situation as a sign of much deeper issues at Boeing, issues that can't be fixed with a simple software update and could affect every plane they make.

Flying -- even accounting for all the 737 Max crashes is still statistically by far the safest form of travel per unit of distance travelled -- the 737 Max is a blip just like 9/11.

[deleted]

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

#138
post #64
post #54

Earlier quoted context omitted.

I would be extremely hesitant to ever fly on a 737 MAX again because, even when MCAS is fixed, software is being used to fix a fundamental physics problem. I'd fly on other Boeing planes without worry, though.

This is not the case. The 737 MAX has different handling characteristics to a regular 737, but there is nothing inherently unsafe about those handling characteristics. The purpose of MCAS was just to prevent the need for pilots to recertify by masking the difference.

> there is nothing inherently unsafe about those handling characteristics

this is not entirely true. applying throttle to the max causes a pitching momentum, something you don't want during a deep stall when control surfaces are totally unresponsive, because it would make the exit procedure (throttle up, nose naturally pitches down, gain airpseed and regain control) unsafe (throttle up, whops the plane is now pointing upward and going backward)

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

#139
post #40

Is anyone else extremely reluctant to fly on a Boeing plane after this? A lot of people say "It's no big deal, they just need to update the MCAS software" , but I see this entire situation as a sign of much deeper issues at Boeing, issues that can't be fixed with a simple software update and could affect every plane they make.

The MCAS will likely be fixed in a way that makes it reliable and dependable. Boeing wouldn't dare anything else since there are a lot of eyes on them and how they handle this now. What worries me is not the MCAS (now), but what else might be lurking under the surface that Boeing pretends is not a problem. I don't feel confident that Boeing would accept the cost of grounding the fleet the next time something serious-…

I don't feel confident that Boeing would accept the cost of grounding the fleet the next time something serious-but-not-yet-crashing shows up.

They wouldn't even ground the fleet if death and destruction occurs. Like they didn't do after the Lion Air crash.

Even after the Ethiopian plane they tried hell and high water, including a call to the president, to not have the plane grounded.

It's clear that to Boeing, their numbers are more important than lives.

Absolutely. Nicely demonstrated by lies, deflections, omissions and still smearing everybody else but themselves after killing more than 300 people by bad design and greed.

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

#140
post #64

Earlier quoted context omitted.

This is not the case. The 737 MAX has different handling characteristics to a regular 737, but there is nothing inherently unsafe about those handling characteristics. The purpose of MCAS was just to prevent the need for pilots to recertify by masking the difference.

> there is nothing inherently unsafe about those handling characteristics this is not entirely true. applying throttle to the max causes a pitching momentum, something you don't want during a deep stall when control surfaces are totally unresponsive, because it would make the exit procedure (throttle up, nose naturally pitches down, gain airpseed and regain control) unsafe (throttle up, whops the plane is now pointin…

I don't think recovery from deep stalls is actually much of a safety issue with airliners. Are there any instances where an airliner has deep stalled and then successfully recovered? By definition, a deep stall is one where standard stall recovery procedures won't be effective.
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