Comment by outworlder | Hacker News Reader

Comment by outworlder | Hacker News Reader

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> Maybe they should have bit the bullet and fully redesigned the 737

That's EXACTLY what they didn't want to do.

Airbus was able to do the 320Neo without a redesign. They essentially slapped new engines on it and made tiny adjustments. Boom, fuel savings.

Boeing wanted to do the same. Their design didn't accommodate the bigger, more efficient engines they wanted. So they created a workaround.

Redesigning essentially means creating an entirely new aircraft, even if it looks similar. Requires a new type certification, which is a very lengthy process in itself. Requires pilot training for the new type rating. Possibly new simulators, and simulator time. Not all airlines even own simulators.

Airlines like Southwest use all 737s exactly because that makes pilots interchangeable(simplifies logistics and maintenance too, but mostly it's about pilots).

If I'm an airline and now you tell me my pilots need training, including expensive simulators, it's no longer the same aircraft(as in, not the same type rating). If it is not the same aircraft, that means I could choose any other aircraft. Such as these new Airbus models I've been hearing about...

See the problem? MCAS wasn't such a bad solution on paper, it's just that the implementation sucked. It should have required some minimal training (which is much better than a new type rating) but Boeing didn't even want that.

> Boeing wanted to do the same. Their design didn't accommodate the bigger, more efficient engines they wanted. So they created a workaround.

Note that Boeing had this problem ever since the 737 Classic (the second generation 737) was introduced, hence the non-circular engine inlets they've had for decades. This cost them efficiency, at the benefit of maintaining commonality with all its advantages.

Note that last I heard Airbus was planning a clean-sheet redesign for the A320neo's successor, targeting an early 2030s introduction into service. If you allow me to speculate for a moment, Airbus is in an interesting position now having the A220 in its family: it could easily stretch the A220 to be comparable in capacity to the A320, leaving an A320 family replacement to focus on the A321 and the smaller midsize market.

I think the world is moving away from twin-aisle planes somewhat. The future is point-to-point in smaller planes. In that sense Airbus is well positioned.

The A321XLR is already a huge success.

You're not wrong but with the crashes an actual redesign is needed.

The crashes wouldn't have happened with a better implementation of the same design.

Probably but now that the public is aware of a physical flaw covered up by a control mechanism the physical flaw needs to be fixed.

I'm not even clear what that fix boeing used to cover up this problem. The article didn't specify, that is a red flag.

The engines being too low is not a physical flaw, and was not the cause of these crashes.

The control mechanism caused the crashes, and control mechanisms can be fixed relatively easily.

This is categorically wrong. The engines being too low will kill everyone on the plane should the special control mechanism not exist.

The control mechanism existed to cover up a physical flaw then proceeded to be the cause of crashes itself.

If a control mechanism can easily be fixed... What was the exact fix? Literally tell me.

> The engines being too low will kill everyone on the plane should the special control mechanism not exist.

It makes the control curve slightly different, don't be so dramatic.

> If a control mechanism can easily be fixed... What was the exact fix? Literally tell me.

I'm not psychic, I can't tell you how they fixed it, but you can find a ton of people talking about how redundant sensors would have avoided the same issue. You could also have it be much more obvious when it's adjusting trim, because if the pilots were aware of what was happening they wouldn't have crashed either.

from your other comment> Saying the control mechanism crashed the plane and just fixing that is like saying you didn't put enough duct tape over the real problem.

Tape, and the equivalent of tape, is a valid solution to many problems if you have an expert analyze it.

>It makes the control curve slightly different, don't be so dramatic.

I'm not being drastic, the plane has an unconventional control system built to hide a physical flaw that is never an actual physical property on planes designed from the ground up. The plane will literally stall:

https://www.thestreet.com/mishtalk/economics/boeing-737-max-...

It's well known boeing used a hack to avoid costs of redesign.

>Tape, and the equivalent of tape, is a valid solution to many problems if you have an expert analyze it.

The experts who killed 300 people analyzed the mcas and also built it. No one will get on a plane covered in duck tape no matter how many experts analyzed it.

>I'm not psychic, I can't tell you how they fixed it,

Makes sense that you're not psychic. Likely you went to google at some point and tried to find out what that fix was and likely you found nothing. That's a red flag, a huge one.

Being psychic is the only possible way you'll know what the engineers did to duct tape the whole design. At the very least this is something any wise man should know about before getting onto that plane.

The plane will stall unless you push the stick differently or adjust the trim. It's something you can compensate for. MCAS doesn't even adjust the trim very fast! It's a hack but that's mainly to avoid retraining, not because the design is inherently all that dangerous.

> The experts who killed 300 people analyzed the mcas and also built it.

It could be fair to avoid all planes coming from those experts. But if you don't trust them to fix a single flaw, why in god's name do you trust them to design an entirely new plane? This is not a reason to push for a redesign.

> No one will get on a plane covered in duck tape no matter how many experts analyzed it.

Ever heard of speed tape?

Most people will either get on the plane when it's fixed, or they will never get on the plane. They're not going to care about the exact details.

> Likely you went to google at some point and tried to find out what that fix was and likely you found nothing. That's a red flag, a huge one.

Sure. Red flag. But a flag is far from conclusive.

> At the very least this is something any wise man should know about before getting onto that plane.

I'm wise enough to not play armchair plane engineer when my life is on the line. If I don't trust the process, then I'll wait for a certain number of flight hours instead. I'm not going to depend on my own ability to analyze plane design.

The locations of the engine did not cause the crash.

The locations of the engine necessitated flawed control mechanism designs which caused the crash.

The locations of the engine and a plane flown without mcas will also cause the plane to crash.

The technical debt transferred over to the control mechanism and now all the engineers and people who worked on and funded the plane are responsible for killing over 300 people. These are peoples lives at stake. Fix the technical debt. Saying the control mechanism crashed the plane and just fixing that is like saying you didn't put enough duct tape over the real problem.

Don't Cover it up.

If this seems unavoidable maybe the government should require all but trivial changes to aircraft to go through the same process. That said, airplanes are still very safe even with these tragic incidents.

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