Boeing new issue with 777X engine support

[Wes Bucey]

So, basically you are advocating that ANY design that is not 100% perfect is a bad design, ignoring the fact that many of the envelope conditions a design engineering team are not always perfectly defined. Have you ever heard that saying perfect is the enemy of good? Have you ever thought that, according to your mind set, SpaceX would not have achieved hundreds of successful reuses of booster rockets? Simply because the initial attempts failed badly?

I think you need to rethink an approach the design and development of highly complex systems as a last generation commercial widebody aircraft. If we were to follow your approach we would think that the whole program of test flights for regulatory approval is a wasted effort. Had the 737 Max test flight program been more comprehensive we might had avoided the two crashes.

Sydney, I think you missed the main thrust of Tidge's comment in your quote.

20 planes built and (presumably flown to be parked on a field) BEFORE testing had assured design and components were safe for life, health, safety was a "HUGE AND VERY LIKELY WASTEFUL EXERCISE."

 

[Bev D]

Well frankly this whole thread is a text -book perfect example of how companies talk themselves into not performing an effective causal mechanism investigation. This all just diversionary discussion of the politics and NOT a discussion of the physics. physics first, then we can talk about the systemic 'people issues' at Boing...

examples:
who cares if the design engineers are insulted. that is their issue. Boing needs to understand the causal mechanism and that has nothing to do with anyone's feelings, education level or semantics about "stresses in the metal". no engineer is perfect and all engineers are subject to hubris, or victims of their executives hubris.

"isolated incident" is fancy talk for "we don't know the cause but we think it is very rare and it will never happen again so we can just continue on our merry way". in reality an isolated incident is an event that has happened once so far. in 'validation or certification testing' the population size is very small - so even one occurrence is not rare. In the world of problem solving physics it is a law that if you don't know what caused an event then you cannot prevent it form happening in the future and of course that means that it will happen again...

the whole debate about whether or not Boing should have known about this or detected in early component level testing (while simulation is great it can only simulate what it is programmed to do and that doesn't always include real world things) is irrelevant to the search for the causal mechanism. until we know this we cannot understand 'how' it happened from a (human) process perspective.

 

[Sidney Vianna]

20 planes built and (presumably flown to be parked on a field) BEFORE testing had assured design and components were safe for life, health, safety was a "HUGE AND VERY LIKELY WASTEFUL EXERCISE."

This statement could only be supported by someone who is utterly unaware of the contracting aspects of commercial airliners and the desperate need to come as close as possible to promised delivery dates, not mentioning the fact the need for ramping up the production lines and supply chain.

 

[Wes Bucey]

This statement could only be supported by someone who is utterly unaware of the contracting aspects of commercial airliners and the desperate need to come as close as possible to promised delivery dates, not mentioning the fact the need for ramping up the production lines and supply chain.

I am and have been very experienced on being a principal on contracts and I am always careful to include clauses covering changes, delays and so far never been desperate enough to use shortcuts or weasel words to explain a shortfall on time tables. I am pretty sure I can find support for my Boy Scout "Be Prepared" methods. In fact, it's an effective pitch point when seeking a contract or countering resistance to my clauses.

 

[Tidge]

So, basically you are advocating that ANY design that is not 100% perfect is a bad design, ignoring the fact that many of the envelope conditions a design engineering team are not always perfectly defined. Have you ever heard that saying perfect is the enemy of good? Have you ever thought that, according to your mind set, SpaceX would not have achieved hundreds of successful reuses of booster rockets? Simply because the initial attempts failed badly?

So many words have been put in my mouth! I've been a part of huge design & manufacturing projects that built exactly one and achieved (and in some cases exceeded!) their minimal design requirements. Few of them were "perfect", but we planned and designed for contingencies. We did low-level testing of foundational technologies of these complicated systems before trying to build a "minimal viable product".

Sydney, I think you missed the main thrust of Tidge's comment in your quote.

20 planes built and (presumably flown to be parked on a field) BEFORE testing had assured design and components were safe for life, health, safety was a "HUGE AND VERY LIKELY WASTEFUL EXERCISE."

Yes. this was my point. Aside from the cost of raw materials and assembly, there is now minimally going to be extra inspection costs, as well as likely rework. I'm not involved with aeronautics, but I do understand the implications to design verification when the units-under-test undergo special handling, especially after an "attributable (or not attributed) cause" event.

Maybe the project saved enough (time, money, runway fees, whatever) to justify building a large number of airplanes that will suffer from component failures... but I can't imagine that those savings could possibly manifest unless the understanding of the failures is done, as suggested by @Bev D . I stand by my parallel path suggestion, if for no other reason than projects love things being done in parallel. Let me know if I am "utterly wrong" about this vis-a-vis commercial airline design and development.

 

[Bev D]

@Tidge you are not wrong. Every major industry has deadline pressures. I can’t tell you how many times I’ve heard “if launch and imperfect design 6 months early we will get 6 earlier months of revenue”, or the “we will beat our competitor to teh market that’s what’s matters. Of course quality failures eat up a LOT of that ‘early’ and not ‘extra’ revenue as well the affect on Customer trust. Launch dates in automotive are pretty hard and fast: Job 1 is actually the first sellable vehicle off the assembly line; it is not quality. The pressure to launch makes many people make dumb decisions. The challenger, 737 max, starliner, …on and on.

However, personal comments and discussion regardign what happened at Boing from a process perspective are useless at his point. Everyone is not wrong in that everything is possible bu we cannot know the truth now. This is beginning to sound like my team is better than your team.

 

[Wes Bucey]

However, personal comments and discussion regardign what happened at Boing from a process perspective are useless at his point. Everyone is not wrong in that everything is possible but we cannot know the truth now. This is beginning to sound like my team is better than your team.

Why are the comments and discussion useless, Bev? I have been following the Boeing lapses for over 30 years since my own run-in in the 1990s. The corporate ethos there has remained ingrained despite turnover in the executive suite. Boeing is a case study in the consequence of ignoring "slow and steady wins the race" from the cautionary tale of the hare and tortoise race.

In my original post, I posed a simple statement:
"I wonder how my Quality colleagues around the world would conduct THEIR root cause investigation and remedial/preventive action."

 

[Bev D]

My comment is about speculation about what Boing might have done wrong (shortcuts, etc.) there is way too much we don’t know. My point was in fact to redirect the discussion to the (physical) causal investigation process.

 

[Wes Bucey]

My comment is about speculation about what Boing might have done wrong (shortcuts, etc.) there is way too much we don’t know. My point was in fact to redirect the discussion to the (physical) causal investigation process.

In my opinion, speculation about errors of commission and/or omission are valid subjects as PART of a root cause investigation. Some examples I have seen or found in some.cases:
Reliance on test results in metallurgical samples from vendor labs labs later found to be easily discoverable with random exams of duplicate analysis reports;
Omission of steps in written assembly procedure;
Incidents of installation of parts in wrong orientation (missed in design FMEA);
Concentrating on material spec failure when true problem was error in load factor in design.

Obviously there are others - I have had a long career.

My point is nothing is off the table in an investigation if investigators start with a new FMEA, setting priorities for order of tests , but not stopping after they find a single cause, perhaps omitting a more frequent and hazardous cause in the next test.

 

[ChrisM]

"isolated incident" is fancy talk for "we don't know the cause but we think it is very rare and it will never happen again so we can just continue on our merry way".

.....and this is a key point. If you could fully investigate and find the root cause of something that is an "isolated incident" to date, there would be more confidence in knowing the amount of action needed to be taken to prevent recurrence. For example of it was because one "rogue" part that was under-size crept through all the inspections and go/no-go checks, what could be done to prevent recurrence and what are the chances of an under-size part being manufactured again anyway? If a part has cracked in service it is essential to find out why; was the stress under-estimated, were the design calculations incorrect so that insufficient material was specified, was there a material flaw etc etc.
"We think it is very rare" is an opinion only; where is the evidence to back this up?