Delays in Boeing Max Return Began with Near-Crash in Simulator • Hacker News Board

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#31

Post by zaroth » Fri, Nov 08, 2019, 2:30 PM UTC

zaroth wrote: post #12

The can of worms has been officially opened, and this may turn out to be a case study in how bad software and outsourcing your centers of excellence can bankrupt a company. If TFA is to believed, Boeing has embarked on a project to take what is currently a master-slave failover design and jury-rig it into a master-master real-time system. This is based on bad performance in the simulator—not because of MCAS—but while…

As a tangent, there have been times when HN is ahead of the curve in understanding where something is headed before the investing public.

The benchmarks and excitement around AMDs offerings are a great example. When you see something that presents a paradigm shift, often the market will not have fully digested it.

AMD is one of those cases, and I believe BA is as well. Their stock is essentially unchanged from where it was before the Lion Air crash in October 2018. This company is worth $200B and we’re talking about 5,000 units of a $100mm plane (that’s $500B in revenue right? I’m not adding a zero there?)

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#32

Post by dhimes » Fri, Nov 08, 2019, 2:30 PM UTC

speeder wrote: post #17

MobileVet wrote: post #4

Considering that MCAS is an added ‘feature’ to avoid stall, you would think they could just remove it and be done. After all, it wasn’t part of the original 737. Sadly, from my limited understanding, due to the engine location change on the airframe, the plane naturally pitches up... making it necessary. One thing seems clear to the external observer, this is a 737 in name only.

Well, it IS a 737, that is part of the problem. The 737 has a feature almost no other new plane have: you can order it with a internal staircase so people can leave the plane without a specialized airport terminal. This feature requires the plane to keep its current overall shape, otherwise the staircase thingy would not work. So to keep this feature, while putting a bigger engine on the plane, they had to move the e…

It was more than a staircase issue- they were trying to avoid time-consuming and costly pilot-retraining.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#33

Post by macspoofing » Fri, Nov 08, 2019, 2:31 PM UTC

cdolan wrote: post #22

Havoc wrote: post #14

Earlier quoted context omitted.

>at least one of the pilots who flew the scenario in a simulator found it difficult to respond And I'm guessing their not using pilots of average skill here...

Correct, I’d wager the best pilots in the world are safety and test pilots.

Maybe. I don't know the intricacies of testing flight control software but I imagine Boeing will have a bunch of professional 'test pilots' augmented with regular pilots they 'borrowed'.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#34

Post by petschge » Fri, Nov 08, 2019, 2:32 PM UTC

speeder wrote: post #17

MobileVet wrote: post #4

Considering that MCAS is an added ‘feature’ to avoid stall, you would think they could just remove it and be done. After all, it wasn’t part of the original 737. Sadly, from my limited understanding, due to the engine location change on the airframe, the plane naturally pitches up... making it necessary. One thing seems clear to the external observer, this is a 737 in name only.

Well, it IS a 737, that is part of the problem. The 737 has a feature almost no other new plane have: you can order it with a internal staircase so people can leave the plane without a specialized airport terminal. This feature requires the plane to keep its current overall shape, otherwise the staircase thingy would not work. So to keep this feature, while putting a bigger engine on the plane, they had to move the e…

Just skipping the staircase it not enough. To make the plane taller it needs a new landing gear. But that doesn't fit into the existing gear wells. So now you need to redesign the gear wells. But the gear nearly touch in the middle already. So you neet to make them taller, and attach them to the wing further out. Which the Wing can' take. So you need to redesign the wing. At this point you better just admit that the 737 design from 1964 is at the end of its life.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#35

Post by danso » Fri, Nov 08, 2019, 2:35 PM UTC

Yizahi wrote: post #7

If I understand correctly "fixing" MCAS would be quick but audit found out more problems and Boeing started basically a refactoring of their computer architecture (including hardware changes) which itself takes a lot of time and didn't pass new audit yet.

Yes, that's the official explanation. But these problems (such as gamma rays scrambling the flight computer, causing the plane to aggressively dive) are ostensibly not new, or related to MCAS. The issue is not just that gamma rays theoretically – and MCAS, in real-life and quite tragically – cause the plane to dive, but that Boeing overestimated pilots' ability to react to the underlying systems error. I think it seems suspicious Boeing only now decides "Oh, looks like we should also modernize the 737 computers", while asserting that MCAS itself was still a great idea.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#36

Post by CaptainZapp » Fri, Nov 08, 2019, 2:35 PM UTC

speeder wrote: post #17

MobileVet wrote: post #4

Considering that MCAS is an added ‘feature’ to avoid stall, you would think they could just remove it and be done. After all, it wasn’t part of the original 737. Sadly, from my limited understanding, due to the engine location change on the airframe, the plane naturally pitches up... making it necessary. One thing seems clear to the external observer, this is a 737 in name only.

Well, it IS a 737, that is part of the problem. The 737 has a feature almost no other new plane have: you can order it with a internal staircase so people can leave the plane without a specialized airport terminal. This feature requires the plane to keep its current overall shape, otherwise the staircase thingy would not work. So to keep this feature, while putting a bigger engine on the plane, they had to move the e…

The other option would have been abandon the staircase entirely and make a taller plane, this would allow a bigger engine with no handling changes, but although this would remain a 737 from handling perspective, it would not be a 737 from the airports perspective: it would need to remodel the airports to install bridges or purchase of ladder trucks.

No that would not be the major problem. Specifically since practically any airport nowadays has the infrastructure to service such a plane. This was quite different 50 years ago.

The reason why they couldn't have heightened it was that a new type certification would have been required and Boeing wanted to avoid exactly that at all cost.

Even at the cost of 346 dead people.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#37

Post by macspoofing » Fri, Nov 08, 2019, 2:36 PM UTC

situational87 wrote: post #19

Are the simulators run by Boeing or the FAA? Are the test pilots employed by Boeing? What changes have been made to the regulatory framework to prevent Boeing from signing off on their own safety tests? What changes has the FAA made to bring more public transparency to the flight certification process? When is the sentencing date for Boeing executives? They are not getting a plea deal I hope? I'm not worried about th…

I'm not sure the FAA is at fault here. From a big-picture perspective, the industry has never been safer.

Obviously, continuous improvement is a core part of quality, and the FAA can always learn and improve their processes, but you can't expect a regulator to shoulder the core responsibility of certifying a plane. The primary responsibility is always going to be on the manufacturer because no regulator will ever have the manpower to test and verify everything nor the deep visibility into to R&D process that a manufacturer would.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#38

Post by anticensor » Fri, Nov 08, 2019, 2:39 PM UTC

davidhyde wrote: post #5

akersten wrote: post #2

These should not fly for a decade. They're rewriting the avionics from scratch. This should require a years-long process of testing, external auditing, and approvals. I'd even go so far as to say in flight, we should require competitor review. That's right, no trade secrets. If you want your Hello World up in the air, you better let your competitor vet the source code. This is an engineering boondoggle and an embarra…

Agreed, the MAX was only designed to beat the competition to market with the least amount of re-certification and re-training. That gamble (with Boeing's reputation, the FAA reputation and most importantly, people's lives) did not pay off. They won't get away with rushing though certification of a complete rewrite of their flight software. The world is watching now. Time to cut losses and junk the MAX entirely.

Slightly redesigning the wings and fitting 4 engines which are sized similarly to ones in 737-400, instead of 2 large engines might solve the problem.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#39

Post by xvf22 » Fri, Nov 08, 2019, 2:40 PM UTC

zaroth wrote: post #12

The can of worms has been officially opened, and this may turn out to be a case study in how bad software and outsourcing your centers of excellence can bankrupt a company. If TFA is to believed, Boeing has embarked on a project to take what is currently a master-slave failover design and jury-rig it into a master-master real-time system. This is based on bad performance in the simulator—not because of MCAS—but while…

A split brain in a plane is a bit of a nightmare. I'm not sure how they can work around it with just two computers.

Re: Delays in Boeing Max Return Began with Near-Crash in Simulator

#40

Post by NovemberWhiskey » Fri, Nov 08, 2019, 2:41 PM UTC

Operyl wrote: post #24

thisisnico wrote: post #8

Earlier quoted context omitted.

Didn't I read from another hacker news poster that the software engineering and design was outsourced? Anyone know?

In the article they mention that they outsourced at least some of it. “ As Boeing and the subcontractor that supplied the flight-control computer, the United Technologies Corp. division Collins Aerospace Systems, worked through these changes, it has at times created tension.”

It is extremely common that various parts of design and manufacture of aircraft are "outsourced". The airframe manufacturer is essentially never the manufacturer for whole subsystems and there is a large subcontracting network.

This is an entirely normal and long-standing practice.