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

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

#21

Post by Operyl »

Havoc wrote: post #14
danso wrote: post #10

FWIW, the near-crash in the simulator was apparently not directly related to MCAS, but occurred when Boeing "simulated what would happen if gamma rays from space scrambled data in the plane’s flight-control computers." > In one scenario, the plane aggressively dove in a way that mimicked what happened in the crashes on the grounded jetliner, the people said. While such a failure had never occurred in the 737’s histor…

>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...

According to [0] the FAA was looking for numerous candidates to get a good range of experience, so I would think that you might’ve had at least a few average pilots.

[0]: https://www.reuters.com/article/us-ethiopia-airplane-faa-boe...

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

#22

Post by cdolan »

Havoc wrote: post #14
danso wrote: post #10

FWIW, the near-crash in the simulator was apparently not directly related to MCAS, but occurred when Boeing "simulated what would happen if gamma rays from space scrambled data in the plane’s flight-control computers." > In one scenario, the plane aggressively dove in a way that mimicked what happened in the crashes on the grounded jetliner, the people said. While such a failure had never occurred in the 737’s histor…

>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.

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

#23

Post by mannykannot »

the-dude wrote: post #6
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.

It is my understanding it is only necessary to make the Max 'compatible' with the 737 so nobody needed to be retrained and recertified.

My understanding is that, without MCAS or some other design change to fix its unacceptble handling characteristics near the stall, the 737 MAX would have been uncertifiable even as a new type. It is the way that Boeing went about implementing that fix, in an attempt to avoid an additional training requirement, that has caused all the trouble.

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

#24

Post by Operyl »

thisisnico wrote: post #8
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.

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.”

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

#26

Post by dhimes »

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…

I hope they aren't expecting people to fly on these planes.

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

#27

Post by alistairSH »

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.

due to the engine location change on the airframe, the plane naturally pitches up... making [MCAS] necessary.

Most jet airliners have a pitch up tendency. The problem with the MAX is two related issues...

First, FAA has a requirement that stick pressure must follow certain patterns - namely, the harder you pull/push the stick, the more the plane reacts. Due to engine placement, the MAX did not meet this requirement.

Second, Boeing needed to create the MAX with minimal (approaching zero) re-training of pilots.

MCAS was supposed to meet both needs - by having MCAS adjust the stabilizer, the stick behavior/feel came back within requirements. And because it was all automatic, the pilots didn't need retraining in the simulator. Correcting the stick feel without a system like MCAS would have required more substantial changes to the plane, which would have likely required simulator time, which was likely a deal-breaker for some airlines.

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

#28

Post by dhimes »

joobus wrote: post #15
macspoofing wrote: post #3

Earlier quoted context omitted.

A decade is too long but I agree with your sentiment. The underlying problem with the 737 Max was commercial pressure leading to cutting corners and creating an unsafe plane (or plane with an unsafe core component) ... and now commercial pressure is again being applied on their R&D teams, which are probably scrambling because they know every day means millions in losses. That's not a great environment for quality and…

Boeing makes up 8.8% of the Dow right now, the largest component. There is a lot of pressure from the finance community and the government to get this recertified to keep the stock market from going down.

Tough shit. Index funds may take a hit, but better a market crash than and airline crash.

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

#29

Post by dmos62 »

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…

> sentencing date for Boeing executives

Are you talking about criminal court? Call me pessimistic, but I don't think our societal arrangement is such where the people at the top pay the price. I think regulation reform is a more realistic goal.

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

#30

Post by alistairSH »

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…

TIL: The airstairs are still an option of most (all?) 737 variants. RyanAir appears to have them on part of the fleet. And many BBJ have them, as not all general aviation terminals have jetways.

I assumed the stairs were not longer installed, and the height of the 737 was just an anachronism.

Video for those that haven't seen them: https://www.youtube.com/watch?v=unZeusTrDX4

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