Hacker News Reader

Comment by seanhunter | Hacker News Reader

Probably the surprising thing is how _few_ orders they have lost. My understanding is that this is because it is very very difficult for an airline to change from Boeing/Airbus to Airbus/Boeing. They need to retool their whole supply chain and retrain all their ground staff and pilots.

...but several airlines are talking about it. Notably American https://airlinerwatch.com/american-airlines-eyes-airbus-a321... and United in the US https://airlinerwatch.com/united-airlines-considers-airbus-a... are both considering replacing old Boeing planes with Airbus.

View on HN

The irony is that, as near as I can retrace the public timeline, American was actually the carrier that bludgeoned Boeing into producing an up-engined 737 in the first place.

http://news.aa.com/news/news-details/2011/AMR-Corporation-An...

In retrospect, a lesson in not letting your biggest customers drive your development pipeline.

> In retrospect, a lesson in not letting your biggest customers drive your development pipeline.

A new airplane program is not, and pretty much cannot be, started without having major commitments from airline customers. They are developed very much based on conversations with airlines and what they need and will pay for.

Still, the decision by Boeing to try to shoehorn the new, bigger engines onto a 737 body, was a mistake. Whose job was it to know that this was not a good idea, because it would make the plane difficult to fly, and thus difficult to train for? Hint: the one that employs a lot of aeronautical engineers, and whose CEO should have been listening to them.

This is a mischaracterization. The problem was everything was being squeezed simultaneously. There are lots of ways to make a 737 that's safe with new engines. A combination of schedule, desire to avoid transition training, and desire to avoid signifiant systems changes made it hard to do that though.

The critical moment was in flight testing when a pitch instability was discovered at low speed and low angle of bank. MCAS originally was a hack, but would have been safe, using a G sensor and AoA to activate. The new low speed instability didn't trigger the G sensor, and needed a bigger trim correction, so they either had to redesign the augmentation system, or make MCAS much less reliable and more dangerous. They chose to ship and meet their deadline.

> There are lots of ways to make a 737 that's safe with new engines.

Yes, but all of the non-insane ways would have required the 737 MAX to be re-certified as a new aircraft type and pilots to be re-trained before flying it. Which Boeing did not consider to be a viable option. And that decision was probably driven by their airline customers, since they're the ones who pay the costs of recertifying their pilots.

> was a mistake

No, it wasn't. The design of the MCAS system was faulty. Jet airliners have used augmentation to compensate for stability problems since the 707, and airliners not being flyable without the help of computers has been the norm for decades.

They are implying that the fundamental design of the 737 MAX was a mistake due to the engines. MCAS is a like applying a poorly designed bandaid to a deep vein cut.

> They are implying that the fundamental design of the 737 MAX was a mistake due to the engines.

That wasn't the mistake. The mistake is several problems with the implementation of MCAS, all straight-forwardly fixable, along with some minor additional pilot training. I think this will turn out to be a business case study in crisis mismanagement.

I also believe pilot error was a significant factor in the crashes, because during the first instance of MCAS malfunction, the pilots dealt with it and landed safely, despite not knowing about MCAS. The latter two incidents were not handled properly by the pilots, indicating a gap in training.

> I also believe pilot error was a significant factor in the crashes, because during the first instance of MCAS malfunction, the pilots dealt with it and landed safely, despite not knowing about MCAS. The latter two incidents were not handled properly by the pilots, indicating a gap in training.

This sounds disingenuous from my reading of the problem. The pilots were not trained in the new system or even told of its existence.

Seems pretty unfair to blame them for not being able to respond correctly within 3 seconds to correct a system that they didn't even know existed and literally makes the plane not respond to pilot input.

I think it's amazing that the other crew was able to survive TBH. Didn't they have to pull a fuse?

https://qz.com/1576597/off-duty-pilot-saved-lion-airs-737-ma...

It was another pilot who was on the flight that knew how to deactivate MCAS.

Hardly seems like "pilot error" when the crew that died didn't know how to deactivate a system they were never told existed.

It could be deactivated by shutting off the stab trim motors. The switches for it are right there on the center console, and pilots are trained to throw those switches in the event of stab trim runaway. The MCAS failure presented itself as stab trim runaway.

It's like if your car engine runs away, you turn off the ignition. It is not necessary to know why it ran away, just that you can shut off the engine. (Which I have had occasion to do.)

yes, but you forget to mention that before the second crash they actually disabled the stab trim motors and they couldn't manually correct the trim trying to turn the wheel with all their strength so they had to reengage them and that activated again MCAS and puff.. Or are you saying that is their fault because they should have been stronger than that killing machine?

Reminds me of the conversations between Pan American's Juan Trippe and Boeing's Bill Allen described in Skygods [0] (don't have exact quote but this blog [1] is close enough).

> With the head of Boeing as captive audience, Trippe laid out his vision for an airliner that would multiply the astounding success of Boeing’s 707 by adding capacity for more than twice as many passengers. Allen, already sitting on the substantive plans of Boeing’s proposal for the USAF CX-Heavy Lift System (soon to be won by the Lockheed C-5 Galaxy), was more than interested.

> The meeting is supposed to have concluded with his famous line ‘If you’ll buy it, I’ll build it.’ To which Trippe replied ‘If you build it, I’ll buy it’.

> And the seed of the Boeing 747 was planted.

[0] https://airscapemag.com/2018/09/25/if-you-build-it/

[1] https://www.amazon.com/Skygods-Fall-Pan-Robert-Gandt/dp/0615...

Sure, but there's an issue in business where people lacking the degree of technical understanding required to evaluate feasibility are the ones that give (or rather demand) the go ahead on a major change.

The relentless promotion of cynically optimistic arse-kissing yes-men will one day doom us all.

This is hugely industry dependent. In the service provider routing industry, for example, many new features are developed after customers request them for their networks.

If you look at the orders by customer[1], you will see quite a few that exclusively or mostly fly 737's.

It would be costly for an airline to have to retrain almost all their pilots, mechanics, etc on a new aircraft...and to purchase all the associated supporting equipment.

And, the Max has significantly better fuel efficiency, seating capacity, etc than other 737 models. Falling back to an earlier model isn't easy either.

They are banking on the general public forgetting about it over time. Which has happened in the past.

[1] https://en.wikipedia.org/wiki/List_of_Boeing_737_MAX_orders_...

> They are banking on the general public forgetting about it over time. Which has happened in the past.

Which almost always happen. Good strategy. Works for politicians, abusive spouses, big companies. What incentive would they have to do otherwise since society most often offers short outburst of rage, then focuses on something else ?

Regulatory agencies that actually work for the public interest would be a good start.

What would be gained by destroying Boeing? And what would be lost?

You don't need to destroy Boeing, but we do need to tell them to suck it up and design a new plane. The sooner, the better.

Not sure, ensuring

1) that the regulation organisms do their job instead of relying on Boeing

2) that the 737 Max MCAS system relies on 3 sensors

seems good enough no?

The three sensors seems unlikely, and is probably a good high level signal as to whether there's a genuine standoff.

There are two AoAs and enough other sensors to cross check with already on the plane.

That would be only a software update.

There's nothing wrong with the 737MAX airframe. It's a software problem with the MCAS system.

Unassisted non-compliance with FAR 25.173 begs to differ.

Keep in mind MCAS would not have existed to malfunction if the airframe was capable of complying with existing regulations unaided.

This fact alone means that the airframe does have something wrong with it.

FAA regs require an active yaw damper, because all swept wing airliners would be dangerously unstable without it.

There is no difference in principle here with the MCAS system.

Except that unstable pitch is more dangerous than yaw?

Yaw instability has resulted in fatal crashes.

I disagree that this is only a software issue: relying on only one sensor is a system issue in the MCAS not a software issue.

The worst part is that there is only one sensor because having only one sensor allowed them to not document it and requiring pilot retraining. They just found a loophole to exploit, it had nothing to do with a single sensor being a good decision.

Some might argue the engine placement is very awkward to accomodate the low slung wings. With predictable outcomes, like MCAS.

Swept wings are also unstable, requiring a yaw damper, and crashes have resulted from inoperative yaw dampers.

Of course, we could demand a return to straight wings, but then air travel would be a lot slower.

The low mounted wings on the 737 are serving a no longer needed niche. They were there to accommodate rolling air stairs, where you walk into the tarmac and walk up aircraft-internal steps to board the plane.

The last time I flew on a 757 (a couple months ago) I got on and off on the rolling air stairs.

Rolling is different, I shouldn't have used that term. The 737 can be deplaned with stairs that are integral to the aircraft.

Ryanair does still use the internal 737 stairs at some airports in Europe.

The perceived cost of making business decisions that are cheaper but have the potential to kill people would go up.

That's also how people defended slavery.

"Eschew flamebait. Don't introduce flamewar topics unless you have something genuinely new to say. Avoid unrelated controversies and generic tangents."

https://news.ycombinator.com/newsguidelines.html

> They are banking on the general public forgetting about it over time. Which has happened in the past.

And banking of course on no more crashes. They're on a tightrope for sure.

Im reasonably sure that they now have the right eyes on this type of issue. I'll concede they hadn't previously.

I'd guess 99% of people don't even notice what plane are flying on.

American already operates about ~400 Airbus 320s vs ~350 B737. [1] United also has ~200 A320s vs ~340 B737 [2].

They both have mixed fleets. Of course the story for carriers with a homogeneous fleet is very different.

Part of it is surely PR posturing though. Both to look good with customers and to improve the negotiating position with Boeing.

[1] https://en.wikipedia.org/wiki/American_Airlines_fleet [2] https://en.wikipedia.org/wiki/United_Airlines_fleet

As I have understood, there are waiting lists at both manufacturers, and they're not short, so short-term changes are probably bad for all parties in that business.

A Saudi company changing could be more notable, because if anyone has enough money to buy themselves a better spot in those lists, I don't doubt it wouldn't be them...

I have absolutely zero affiliation with the airplane industry, so everything I said might only be coincidentally true.

Yes I think this would be a major point. Airlines are worried about what happened straight after 9/11 were many cut orders, then places like Ryanair option loads of aircraft at discount prices, then airlines struggled to get back into the booking list. There is a waiting list of many years at the moment. They would be a bit crazy to ditch their spots right now.

https://news.ycombinator.com/item?id=20376062 explains why: Airbus is "sold out", can't deliver more planes in the timeframes that are required. The airlines don't have much of a choice.

The whole design behind the max was to minimize pilot training and retraining. The airlines have as much to gain from retooling an existing design as Boeing has.

Of course this will shift some orders towards Airbus. But besides that Airbus won't be able to deliver additional orders on short notice, the airlines certainly don't want to give Airbus too much power by dropping Boeing completely.

Unsure about American, but I am sure that United flies A320/321 and 737s both, so I don't see how switching would be that hard for them. Maybe just due to pilots?

Reply on news.ycombinator.com