Hacker News Reader

Comment by nobodyandproud | Hacker News Reader

Nearly 23 years ago: ‘A Boeing aerospace engineer presented a controversial white paper in 2001 at an internal technical symposium. The engineer, John Hart-Smith, warned colleagues of the risks of the subcontracting strategy, especially if Boeing outsourced too much work and didn’t provide sufficient on-site quality and technical support to its suppliers.

“The performance of the prime manufacturer can never exceed the capabilities of the least proficient of the suppliers,” Hart-Smith wrote. “These costs do not vanish merely because the work itself is out-of-sight.”’

https://www.wsj.com/business/airlines/boeing-manufacturing-7...

View on HN

“The performance of the prime manufacturer can never exceed the capabilities of the least proficient of the suppliers”

Software connection: this is known as SLA Inversion [1], the phenomena that you can never be more reliable than your least reliable component. There are ways to get around it, but they involve having multiple redundant but independent paths to achieving a successful result. This is difficult for structural components of an aircraft because each redundant mechanism adds weight and decreases performance & fuel economy.

It's somewhat shocking to me that there are no redundant failsafes to something as critical (and potentially error-prone) as a loose bolt in a door plug, though. Or maybe there were and we'll see compound errors in the final FAA report, which will definitely be interesting to read.

[1] https://sookocheff.com/post/architecture/stability-antipatte...

> This is difficult for structural components of an aircraft because each redundant mechanism adds weight and decreases performance & fuel economy.

All structural (and other flight critical) components in an airliner are redundant. And yes, they add weight, decrease performance, and increase fuel consumption.

As for the door, it is also redundant. We'll have to wait and see to find out what the exact cause was before finding a solution.

The obviously loose bolts are certainly a problem. The process should be one mechanic installs the bolts, then an inspector inspects it and signs off on it.

If you watch "Aviation Disasters" (I watch all of them) there's always multiple causes for each accident, and multiple fixes. One crash happened because a maintenance worker taped over the redundant sensors so the airplane could be cleaned, and forgot to remove the tape. The inspection to ensure the tape was removed also failed.

Famously, the 'swiss cheese' model [0, critical article] - every layer has holes, so layers of safety are required to reduce the chances of holes lining up (leading to a failure dropping though - and resulting in an accident).

[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1298298/

I’m genuinely curious how you would consider the door (plug) redundant. What else is keeping things (e.g., the mobile phone that fell to the ground) inside the airplane?

> It's somewhat shocking to me that there are no redundant failsafes to something as critical (and potentially error-prone) as a loose bolt in a door plug, though.

There were warning lights going off suggesting a depressurisation was going to occur, but these were broadly ignored (though flights were restricted to shorter routes).

Not quite a fail safe but also not an ideal response.

https://www.kptv.com/2024/01/08/watch-live-ntsb-officials-gi...

That's not what those lights mean. The warning was for a malfunction of one of the triple-redundant pressure control systems.

> Homendy said investigators have learned that before the Friday flight, the “auto-depressurization” warning light came on during or after three previous flights, at least one time while the aircraft was in the air, and once while it was on the ground. Each time, the light was checked out, and Alaska Airlines reported the light turning on was a “benign” issue.

Homendy addresses this in the media brief: https://www.youtube.com/watch?v=0jeO5fwRXLo&t=257s

Homendy's remarks were obviously wrong and premature (sadly expected of the "chair" who is an administrator, not the qualified engineer.) The Alaska Air 1282 plane experience 3 different warnings. The system is "semi" triple redundant in that there is a primary system, a secondary system, and a manual system. In this case, the primary system was "failing", and the plane switched over to the secondary system. Alaska has not explained itself here.

However, the most obvious speculation, is that the plane was leaking (badly) and the primary system was probably keeping up with the leak (which is why the problem was intermittent.) But that primary system was likely have to "run all the time" (because it had to keep up with the leak) - and one of two (or both) things likely happened. Either sometimes it could NOT keep up (based on elevation, pressure, and temperature variations), or else the pressure pump was actually overheating (from constantly having to run to keep up with the leak), and occasionally failing. When this happened, the plane control systems would automatically switch to the secondary pump, and light the WARNING LAMP. Given that the problem happened twice in the prior 3 days, the problem was getting worse.

AlaskaAir's response was totally inappropriate, and NOT safety focused. They did not ROOT CAUSE the issue, HOPED it was the lamp, or lamp electricals, replaced those parts, and called it good. And the 4th time was the charm, when the plug failed entirely, there having been 3 prior warnings of an issue in pressurization. In my opinion, inexcusable, and the reason I am no longer flying on AlaskaAir. Though I would further speculate that Boeing's inspection procedure instructions probably do not include inspecting the exit door seals, the door plug seal, or the rear pressure cone. Inspecting those things would be much more expensive than just checking the warning light, and the pump operation. (The pressure pumps operating just fine, and the LAMP just fine as well.)

So Homendy's statement is almost certainly expected to be shown to be misplaced and premature. I was incredibly surprised that she made the statement.

A chain is only as strong as its weakest link.

That's why every critical thing in an airplane is redundant.

> That's why every critical thing in an airplane is redundant

I'm not sure how to understand that claim. Do the emergency doors/door plugs have two bolts? Three bolts? Ten bolts?

If the manufacturer and/or the operator is not capable of making sure that all the bolts are always appropriately tightened, what is that claim actually worth?

> One crash happened because a maintenance worker taped over the redundant sensors so the airplane could be cleaned, and forgot to remove the tape. The inspection to ensure the tape was removed also failed

So from that we learn that failures can stack, just like like redundancies?

> Do the emergency doors/door plugs have two bolts? Three bolts? Ten bolts?

I don't know the design. But I'm sure it is not one where one bolt failing will cause the door to come off.

> If the manufacturer and/or the operator is not capable of making sure that all the bolts are always appropriately tightened, what is that claim actually worth?

The process also has to be redundant. One mechanic tightens the bolts, and an inspector checks it and signs off on it. If there are loose bolts shipped, then the inspector has some 'splaining to do.

> So from that we learn that failures can stack, just like like redundancies?

Zipper failures are not supposed to happen. Any crash is the result of an unexpected zipper failure. The whole airline system is extremely complex, and finding every potential zipper failure is nigh impossible, though everyone involved tries to anticipate every scenario. When a zipper failure happens, then each event in the zipper is corrected.

This is how airline travel, an inherently dangerous activity, has become so incredibly safe.

> This is how airline travel, an inherently dangerous activity, has become so incredibly safe

Indeed. The tragedy with Boeing though is that they seem to have greatly regressed when it comes to safety. We all thought planes plunging down to the ground, doors getting ripped off of the fuselage were a thing of the past but they have reappeared.

> I don't know the design

Doesn't that feel just a little awkward, to first claim "every critical thing in an airplane is redundant", yet when asked for specifics to have to resort to saying you "don't know the design"?

FWIW, I'm sure aircraft are safe. At least, "safe enough" [usually].

Yet we all know they're built by humans working for corporations, and we also know both humans and corporations are sometimes flawed.

> Zipper failures are not supposed to happen

Right. Every so often they do, though, don't they?

They have four bolts. Two at the top and two at the bottom.

> They have four bolts. Two at the top and two at the bottom. reply

So how many have to fail for the door to open?

In other words, if three fail, can one still keep the door shut?

One can keep the door shut, yes. It is kind of a weird system. The plug is actually "held in" by the plug stops in the frame (12 of them). The plug stops align with 12 mating stop-mating-pins and contact (on the plug, e.g. "door"). The way the plug gets into that position is "interesting". It tilts up from the bottom on the two lower hinges. Then it is lifted "up" so that each plug contact point and pin rises "above" the corresponding door stop. Then the door is pushed "in", so that those same contact points are now in a plane "hehind" the door frame stops. Then the door is lowered down, so the pins align with the stops. Normally air pressure would keep the door's pins and contacts aligned with the stops. But on the ground, when there is no pressure, the door needs to be secured from "upward movement". Its really, backward movement (push-in to release the pins from the stops, AND THEN upward movement, so that the pins and contacts then clear the door frame stops. Then in a control removal, the door is pulled out from the top, the pins and contact clearing the frame contacts, and hanging in the air on the hinges, and some straps. Then the door is supported, the straps removed, and the door lowered, or totally removed.

The job of the 4 bolts is to "hold" the already placed and aligned pins/contacts that are in contact with the door frame stop brackets, in the "outward direct contact position. These bolts also serve to prevent the door from translating "upswards as well." The pins also prevent upward alignment, but they are not as strong, they are really for alignment. The contact point bracket (with a pin in the center), and the door frame stop bracket really hold the door against air pressure.

The bolts keep the door from pushing back into the plane (on the ground, with no air pressure), and also present the door from "sliding up" such that the door contacts and the frame contacts would not longer contact.

The alignment and door plug placement (for insertion, and removal) is aided by guide tracks on the panel, and guide track rollers that are mounted to the door frame.

On flight 1282, the door plug's roller tracks were described as badly damaged.

Any one of the door plug "retention" bolts properly torqued would have been adequate to hold the contacts with pins, in position. Any two (one top, one bottom), properly torqued would have been adequate to prevent roller track damage from vibration, door weight, in flight turbulence induced vibration. All four provide dual redundancy. (Two diagonals, or two, one up, one down.) While the NTSB has been totally silent thus far, it seems that the bolts were likely missing in their entirety, or all 4 bolts were so loose, that the bolts backed out until missing, or only one or two "lose" bolts remained. The bolts don't work if there are not tightened to torque spec for holding the door plug contacts in place against the door frame stops.

So, yes, this assembly did in fact have typical critical system redundancy. And it hard warnings on the pressurization system on whole (many possible causes). While Boeing or supplier (or probably BOTH), and the FAA all failed in new plane inspection, AlaskaAir failed with the pressurization warnings. (3 prior faults.) Extremely disappointing how the entire manufacturing chain, and operational chain BOTH failed here for this event to occur.

Really, cannot call this event an accident. An accident is something like the torque wrench being mis-calibrated. (Though that is still a manufacturing or maintenance fail.) But in this case, supplier fail, Boeing fail, FAA fail, AlaskaAir (3 times fail). Pretty despicable really.

That's why there are two wings.

That's not enough, planes should have twin booms. P-38 got it right.

I believe we're going to find that it wasn't a single loose bolt, but that all for bolts were missing, somehow.

No, then the first pressurization would have led to the plug being blown out.

No. The bolts don’t hold the door/plug against the pressure. There are 12 stops and brackets, separate from the bolts, that take the pressurization load and transfer it to the airframe. The bolts are there to simply prevent the door from translating upwards from behind the stops (as it would when opened as a real door).

The bolts could be missing and it could take some time (vibration, landings etc.) for the plug to work its way upwards from behind the stops.

You've got that 100% backwards. The 12 stops stop the door from moving inward, the only thing that stops the plug from moving outward is the bolts. See the widely circulated drawing of how that plug is constructed, I think you have inside and outside mixed up.

Sorry you couldn't be more wrong here. The parent post describes this correctly.

The door rests on the stops (on the inside) which transfer 100% of the pressurization load (from the inside out) into the fuselage. The stops look to be welded or part of the structure. There is no need to prevent movement inward because the force under pressurization is in the opposite direction! This door is apparently a 20 year old design, used on the legacy pre-MAX 737, it was not conceived by idiots.

The bolts don't carry this load at all. Their purpose is to keep the door from sliding upwards vertically up and over the stops.

The operation of the door for maintenance e.g. like opening a window for ventilation, the bolts are removed, the door is then lifted upwards with the help of springs, sliding past the stops and pops out. There looks to be a small strap to help keep it propped open.

Likely the presence of any one of the four bolts that restricts vertical movement would have prevented this, at least until it was discovered at a maintenance checkup.

It's possible the door was sitting on the stops with no bolts and enough landings happened inducing vertical loads to cause it to gradually slip out of place. Similar to how you can hold a mattress on top of your car with friction and your hand for a period of time, it just takes one gust of wind in the right direction and the rest is history.

> The door rests on the stops (on the inside) which transfer 100% of the pressurization load (from the inside out) into the fuselage.

No.

https://www.reddit.com/media?url=https%3A%2F%2Fi.redd.it%2Fq...

The drawing is from the inside of the plane. If it had been the other way around the door could have never gotten past the stops. And since it is from the inside that means that the stops themselves (which are stops, so they're not bolted into the door, just into the fuselage, the plug door is just resting against them) can't hold the door against the fuselage pressure any more than you can push on a rope. For that you need those bolts, they are the elements that provide the tensile strength counteracting the pressure in the cabin. That's also why the bolts coming loose led to pressurization warnings. If there had been no bolts the whole plug door would have come out immediately. The stops ensure that the door sits flush with the outside of the aircraft and it's the bolts that pull the plug door against the stops.

I'm going off what the NTSB said, you're citing Reddit and developing your own interpretation of a diagram you do not understand.

When you pull the door closed, the stops on the door are ABOVE and BEHIND the ones on the fuselage. The door then slides DOWN to lock it into place. So under pressure the tabs on the door push AGAINST the ones on the fuselage. The bolts prevent the vertical motion to unlatch the door and do not carry any pressurization load.

> they are the elements that provide the tensile strength counteracting the pressure in the cabin.

There are NO bolts here carrying tensile loads, shear loads only.

Source: https://www.youtube.com/watch?v=0jeO5fwRXLo

At 1m40s the chairwoman of the NTSB explains why you're wrong. I'll accept your retraction anytime. :)

I'm going by the construction drawing which is 100% unambiguous and not a bunch of words. Reddit has nothing to do with it, that's just one place where this Boeing sourced drawing can be found.

The NTSB comment is just about the fitting guides not about the stops, and yes, they stop the door from moving upwards. There are no bolts through the stops and they do not mesh into any part of the door as far as I am aware, nor does the drawing show anything that they can slot into, it's just a bit of pressure. If it isn't the bolts providing the tension then it would have to be some other mechanism but none is apparent on the drawing. I'm sure the bolts will also stop the door from moving vertically, just as much as they stop if from moving laterally, the key bit is that if they do not engage that the door can slide up and outward and into the airstream on the side of the plane, which is a formidable force. After that it is just a matter of time before the door will escape.

The big question for me is whether all of the bolts had to come loose before the door escaped or whether it was enough for one or two of the four that were loose to come out to do start a feedback loop (door goes off a bit, more air, more vibration and so on). I also wonder if they'll be able to recover the bolts from inside the airframe or whether they've been lost.

> I'll accept your retraction anytime. :)

This is the sort of dumb comment that you may want to take elsewhere.

It is 100% possible that my reading of that construction drawing is wrong, but you haven't shown where or how it is wrong, just that the NTSB person said something that is either incompatible with the drawing or that there is a discrepancy between my understanding of the drawing and reality. If you want me to progress in my understanding you'll have to explain, not demand because nothing the NTSB officer said helps with that understanding other than to contradict, which is a good indication that I'm wrong but not how I am wrong. All she talks about is 'matching circles' but those run in a different direction than against pressure so I really don't see how that matches the drawing. It's possible the stops hook over the corresponding parts in the plug but that's not readily apparent from the drawing at all.

> I'm going by the construction drawing which is 100% unambiguous and not a bunch of words.

It's not a construction drawing, it's a cartoon showing the door in the open position and you are assuming (incorrectly) the operation of the door.

This will be my last comment on this topic because this argument is fruitless and you seem unable to see it any other way. That said:

This is a high res photo of an installed door plug:

https://nitter.privacydev.net/pic/orig/media%2FGDk50Aaa4AEsm...

You can clearly see the "stop fittings" on the door are on the INSIDE and rest on the ones connected to the airframe, preventing outward movement.

When the door opens, it slides up along those two black cylindrical things at the bottom, the stops move past the matching ones on the fuselage, and it hinges outward.

Wow what a great photo, thank you for posting this, I have not seen it. I see two of the bolts near the top, where are the other two?

> It's not a construction drawing, it's a cartoon showing the door in the open position and you are assuming (incorrectly) the operation of the door.

Fair enough.

> This will be my last comment on this topic because this argument is fruitless and you seem unable to see it any other way.

That's a wrong assumption on your end, it's just that I prefer to go by actual evidence rather than a bunch of unsourced claims no matter who makes them.

> This is a high res photo of an installed door plug:

So, finally something useful: the stops apparently hook over the brackets bolted to the airframe, that wasn't obvious from the drawing but I suspected it might be the case (see other comment). So pressurizing the aircraft will provide some holding force (the friction on the stops) even if all of the bolts would be missing or had come loose at any point after assembly.

Thank you for providing the picture.

It's OK to say "I was wrong". No one will think less of you for acknowledging your error and correcting it.

Yes, I was wrong. And I've been wrong before and likely will be wrong again in the future.

You’re wrong. The stops take the pressure load, that’s why there are 12 of them and they are beefy. The bolts simply keep the door behind the stops, that’s why only 4 bolts are needed for that.

I recommend looking up Juan Brown's blancolirio channel on Youtube and watching his videos about the incident and the plug door.

Sorry but you are completely wrong here.

That's possible, but saying it is so will need to come with an explanation of how I'm wrong and how your view matches the construction drawing that I linked because I think that drawing is kind of important, going on the assumption that it really shows the situation in the aircraft. Either there is some trick to the installation process that isn't readily apparent or some other detail that I'm missing.

No, I won’t provide such an explanation or attempt to convince you any further. It’s not “my view” it’s just how it works. Plenty of videos and photos online demonstrating how the door works, you can easily go find them and convince yourself.

Edit: I’m feeling charitable so here’s one, knock yourself out. https://www.youtube.com/watch?v=maLBGFYl9_o

When the door plug is installed, the stop pads on the plug pass the stop pads on the plane and then the door is shifted vertically to align them, with the pads on the plug on the inside of the pads on the plane.

Instead of arguing about it, maybe consider which way the pressure is pushing during various phases of operation and decide how you would design the thing if the highest forces push outward...

> When the door plug is installed, the stop pads on the plug pass the stop pads on the plane and then the door is shifted vertically to align them, with the pads on the plug on the inside of the pads on the plane.

Indeed, picture provided by another poster above shows that is exactly how it works.

And I covered that eventuality in another comment:

> It's possible the stops hook over the corresponding parts in the plug but that's not readily apparent from the drawing at all.

I'd be really surprised if it was just one loose bolt that would allow this to happen, but I don't know. It would be hard to believe they were that stupid, so I'd rather not assume.

I'm not a structural engineer or anything, but I don't see how a single missing bolt would allow this to happen. It would have to be at least the two upper retaining bolts, neither of which were particularly picky about torque and both of which had cotter pins on castle nuts, ideally.

In my humble, ignorant opinion, this. You heard it here on the Internet. :)

Last I heard, though, none of the 4 main bolts were recovered, and they were going to do lab tests to try to determine if they were present to begin with.

When I test-drove my 1980 Datsun, the owner had just been working on the brakes. As I drove with him through the neighborhood, I kept hearing a clunk. I thought it was the transmission. Then at about 40mph, the rear driver's side wheel detached and went flying past my door. The rear of the car skidded on the axle until I managed to get it to a stop.

Turns out the guy's family had come over right as he was tightening the lugnuts and he forgot to finish them. Maybe only one was properly tightened.

He'd wanted $5k for it, but I offered him $2800 as we retrieved the wheel and he accepted.

Right but that's not a single fastener. A single missing wheel bolt or lug nut is not a catastrophic problem. If all of them are loose or missing that can be a problem.

I mean, there's a reason there aren't just two. The other ones aren't just for backup but to reduce the stress on each other. So if you have a situation where you think you only needed two, but only one is tight, the other one shears off. In that case, it's one bolt that broke because one other one wasn't tight.

Speculation: if none of the 4 bolts were tightened, the bolts may have vibrated loose one by one. The door blew out when the last bolt fell out.

Or the wrong bolts were used - bolts that were not strong enough.

Or the particular batch of bolts used were not heat treated, making them not strong enough. (You can't tell if a bolt is heat treated by looking at it.)

Unlike you I have less than no background in this, most especially in aero, but if the faults were as basic as you've described, that would be not failure but outright engineering negligence.

It's not engineering negligence. It's the process that is supposed to implement the design.

That said, it's also a goal of engineering to make the process easier. One such technique is to design things in patterns. Then, if something doesn't fit the pattern, attention is easily drawn to it to investigate the problem. Design things so that when they look right, they are right. For example, look at the line of rivets holding an assembly together. They should form a nice neat pattern.

I try to write software the same way. I lay out the code in patterns. Anything that looks out of place in the pattern draws attention as being a mistake.

> It's the process that is supposed to implement the design

Not sure I understand, are you saying that this is a failure not of engineering but of processes? In that, the original engineering was sound but somebody took shortcuts in the implementation? Or do you mean something else?

Watch Mayday. There are a number of accidents that were caused by a single bolt, but it is usually a systemic series of faults that allowed that to happen as was the case for Flight 17: https://www.avm-mag.com/a-loose-bolt-and-lives-lost-the-cras...

Airbus was a masterstoke of international politics as much as it was of technology in that it involved a high level of international cooperation that was completely successful. (Compare that to the corruption-driven procurement that left Superphenix with broken steam turbines)

Boeing’s outsourcing plan was quite similar in that it discouraged many countries that might have been able to enter the competition for airliners, say Japan, from doing so. Japan very well might have decided to subsidize and otherwise help domestic manufacturers but didn’t feel they had to because they made the tail of the Dreamliner.

From the same article: ‘Airbus CEO Guillaume Faury, in a June interview, said the plane maker faces similar risks with its own suppliers—many of which Boeing shares. But he said Airbus has largely been able to avoid major problems with its quality-assurance approach.

“We are quite intrusive on what suppliers are doing,” Faury said. “We always have to remain very prudent and very humble—you don’t know what could hit you tomorrow.”’

… ‘When it [Spirit] needed to ramp back up, not only did Spirit have fewer people on site, the company had lost years of expertise. There were fewer experienced mechanics, but also fewer experts who could inspect the quality of their work. … Boeing’s demands for lower prices left Spirit strapped for cash as managers panicked over meeting increasingly demanding deadlines. Boeing routinely had employees on the ground in Wichita and conducted audits of the supplier.’

Leadership issue from Boeing : Completely disparaging and underestimating the deep skills of manufacturing and engineering through-and-through.

What was Boeing even auditing? And guess who’s left holding the bag of awfulness?

Can confirm. I worked as Airbus' tier 1 supplier and they were even accompanying us to manage our own supplier, which in hind-sight, ensured that things like this didn't happen.

That sounds a partnership: They’re there to help.

In essence, did Airbus help advise what sorts of corners could/couldn’t be cut?

The way the project was structured, it was in the interest of everyone to succeed since everyone paid for their own development cost and only made money when the planes were sold. Not the easiest client to work for mind you - I've been told that many companies flat out refuse to work with them, but again, thinking back, I think that's what made the project a success, although extremely stressful.

Some customers you can't afford to have and some you can't afford to lose, especially not the ones that help you to perform at (or even above, by educating you) your potential.

Yep - certainly lessons learned through painful experiences.

Supply chain management is incredibly challenging and it's interesting to see one school of thought moving away to vertical integration as an alternative solution and another doing just as well with suppliers (Airbus, Apple, ASML, etc).

this applies to an entire national economy, Silicon Valley was successful due to having hardware and software right next to each other, same thing for US manufacturing in general when we were a powerhouse.

We then let our government get bribed by Wall Street to allow outsourcing everything for a few decades of short term profit. Now China has the manufacturing ecosystem that allows them to innovate more efficiently

Yup. Speaking as an embedded engineer, outsourcing at least some manufacturing to China (or other Far East empires) is often the only road to profitability with modern hardware. Doing so significantly impacts the momentum that can be achieved.

> Doing so significantly impacts the momentum that can be achieved

In a good way or a bad way? I can think of a few success stories that are dependant on China’s manufacturing prowess. I’m typing this on an iPhone.

Both/neither, I would suggest. Offloading manufacturing reduces risk, but requires you to have better oversight in other areas before actually shipping.

From what I've seen, businesses will often hire someone with specific experience dealing with Chinese manufacturers in their specific vertical, for example PCBs/electronics, tooling like injection molds, or textiles.

There is something to what you say, but the continued success of both Apple Silicon and Nvidia processors seems completely opposed to your statement. How do you reconcile those two things?

The cost is a near-monopoly, as the level of strong-arming required is only possible if the loss of business—from shoddy, corner-cutting work—is otherwise catastrophic to the outsourced supplier.

Example: You mention NVidia as a success—and they are—but reliable middle-tier builders like EVGa simply could not remain in business in the graphics card business.

Eventually only NVidia will be supplying their own GPUs and cards.

This in turn significantly drives-up the cost of hiring good local talent if the need ever arises; as TSMC discovered when setting up shop in the US.

How is China's economy doing? Also, the US economy is running near full capacity; what would you have the US move offshore in order to bring manufacturing onshore? Or would you allow more immigration and foreign investment?

The US economy is running at full capacity, but it could be that the some part (20-30-40%) capacity is being used in absolutely poor performance areas.

Why would we think the productivity of those resources would be higher for manufacturing?

I didn’t interpret “poor performance” as “productivity”; rather, as “low-value”.

Basically. If you brought back manufacturing to some parts of America it would likely lead to economic growth. Instead we have the offshoring to cheaper countries.

Why do we assume that? Manufacturing economies were high-growth in the mid-20th century; we don't want to return there.

One reason: Our ability to prototype, build out ideas, and in general innovate is more complicated and less scalable.

The fastest international delivery isn’t comparable to driving 30 minutes to shop for the parts needed for some wild idea (etc.), but that market no longer exists in the US.

In addition to delays, that makes R&D more specialized and therefore more expensive; not to mention the local loss of expertise by the sellers of the components.

Just trying to build some Arduino ideas: I’m looking at $$, planning, and days of shipping. No opportunity to try something out on the spur of the moment.

Our ability to prototype, build out ideas, and in general innovate is more complicated and less scalable.

It's also predicated on people that are intimately familiar with the underlying manufacturing. Lose the manufacturing, and in a generation you're left only with people who know the current designs but lack the knowledge and experience essential to continue innovating.

Exactly as you say: when you no longer have 30-minute access to experimental parts and in-depth advice, your ability to innovate suffers.

Read the book “How Asia Works” by Joe Studwell

Yeah the MAX itself isn't as much of a problem as the outsourcing.

Spirit is a financial tire fire. They've had zero gross margin since the pandemic and they're now burning through half their revenue in interest payments on top of that. Boeing is offloading those losses onto them in order to juice up their own profits. Boeing should probably just be forced to reacquire them.

Clarification for anyone who is as confused as I was: Spirit Aerosystems, not Spirit Airlines. Spirit Aerosystems is the subcontractor that made the door plug. It was spun out of Boeing in 2005 and still has tight employee connections. Spirit Airlines has no connection to Boeing; they actually run an all-Airbus fleet.

There is another effect, if the dependency is strong enough suppliers can intentionally lower the quality to force Boeing to buy them out with much greater profits than they would have made from continuing as a normal supplier. Thus suppliers have an strong incentive to lower quality to unsafe levels and Boeing has a strong incentive to not do anything about it.

Apologies: The actual white paper as well - https://www.documentcloud.org/documents/69746-hart-smith-on-...

Hindsight is 20/20. I'm sure one could go back and read thousands of these internal technical symposium papers criticizing X or Y or Z, and most of those turned out to be unwarranted.

The 'hindsight is 20/20' comment only works when someone points out the problems after the fact. When someone mentions it before it happens the correct comment is 'they were right and we should have listened to them'.

> “The performance of the prime manufacturer can never exceed the capabilities of the least proficient of the suppliers,”

It's also limited by the least proficient of their internal functions. Internal or external makes no difference in that respect.

I see a risk of this thing being "Conways's Airplane" like the law that says your software will be structured like the team that made it.

Yet another example of not just the inability, but the unwillingness to engage in managerial accounting.

These companies primarily focused on financial accounting and even use EPITDA as an internal metric. They do not consider the true costs, such as, people dying or being traumatized by the use of their products. They do not think about the costs of such decisions 20 years into the future. These executives are motivated primarily by their performance with regards to their own personal shares.

Quarterly reports are the rear view mirror. Making projections into the future is the road ahead of you. A focus on short term goals leads blown out windows and aircraft falling from the skies.

This is how the tech industry is managed as well. It is not “enshitification”, it is rather corporate incentive structures and a general level of incompetence. Pure tragedy, the hero CEO brings his own downfall upon himself with only the audience capable of understanding the reasons why.

>These costs do not vanish merely because the work itself is out-of-sight.

This quotation isn't technically true. There are actual costs that do vanish depending on who you contract to. This is completely independent of quality. They are orthogonal.

The sacrifice is characterized as a guaranteed drop in quality if costs are lowered. No. When you sub contract quality is just harder to control. You are rolling the dice. But depending on the sub contractor there can even be an increase in quality along with a cost drop.

For example: iPhones. Subcontracted to china. But pretty high quality. Of course apple had to move over qc to china but there was still overall an up in quality with a cost drop.

Could someone who disagrees with this offer their counterpoint?

Haha. This is an illustration of human bias.

You can't find a counter point on your own so instead of building a conclusion based off of evidence you call out to others to provide you with evidence so you can support your desired conclusion.

A more charitable read of the question could be: GP reads a compelling argument about a topic they have little expertise in, and are curious if there are dissenting opinions.

We can also talk about how much to trust comments on hacker news generally, but multiple data points from any quality of source are better than one.

This is true. I'm assuming disagreement in general because my post has negative karma.

I therefore think it's more realistic to assume that he disagrees. But you're right I could be wrong.

Anyway my comment was very general. And I offered a anecdotal counter point. Falsification only needs a single piece of evidence as proof.

A single example of a sub contractor who is both cheap and high quality will falsify the general quotation here. There is literally no stronger argument in existence. So not surprised that people can't find a counter point as what I offered is literal proof.

Other then dismissing the quality of iPhones coming out of china, At best one can counter by changing the topic of the debate. You could say that in general there's a trend of lower quality associated with lower cost and that while it's not strictly true, it could be generally true. But that's not the argument.

In fact on that topic i am not making such a strong claim that it isn't true. For that topic I literally don't know.

I agreed with your post, but was confused by the heavy downvoting and wanted to understand what I was missing.

Apologies I thought that response was meant for me rather then an actual request to listen to counter examples.

My guess of what may have happened reading between the lines is - Boeing originally possibly instructed Spirit to loosely fit the plug and not secure it because they planned to remove it to fit out the interiors. In this case Boeing would be accountable to secure the plug door after the interior is done to the right specs

Somewhere down the line, Boeing possibly decided not to remove the plug and instead just load interiors through the bigger openings only. They possibly either did not document this change and think through implications and instructions changes for Spirit to secure the door plug instead or did so but Spirit possibly missed. So the bunch of planes may have been delivered with loose plugs that Alaska and United found.

All the implications of outsourcing without sufficient supervision and hand-offs made in the parent point would have a bad effect. The question FAA is probably asking is if Boeing or Spirit has deviated from documented production practice in this area, have they deviated in other areas.

Reply on news.ycombinator.com