[HN Gopher] The Air Force is having to reverse engineer parts of... ___________________________________________________________________ The Air Force is having to reverse engineer parts of its own stealth bomber Author : alrs Score : 138 points Date : 2021-03-03 20:04 UTC (2 hours ago) (HTM) web link (www.thedrive.com) (TXT) w3m dump (www.thedrive.com) | jaytaylor wrote: | Dupes / other identical submissions: | | https://news.ycombinator.com/item?id=26321523 | | https://news.ycombinator.com/item?id=26322477 | | --- | | As an aside, does it still qualify as a dupe if there wasn't any | significant discourse? | Jtsummers wrote: | Re aside: | | Generally no. Some submissions just don't take due to poor | timing (not lining up with when an interested audience will | catch, upvote, and discuss it). | jb1991 wrote: | This is _exactly_ the sort of problem that Jon Blow talked about | in his talk about preventing the collapse of civilization [0] -- | the human race forgets how it does amazing things. | | [0] https://news.ycombinator.com/item?id=25788317 | Pokepokalypse wrote: | This is not new. | | Older planes and other hardware have LONG had to be reverse- | engineered (including microchips). | dmurray wrote: | Reverse engineering seems like a good skillset for the DoD to | nurture, anyway. Yes, the US is going to be at the cutting edge | of weapons design at least through the medium term, but the | leadership isn't arrogant enough to think that _all_ engineering | innovations will come domestically. If the US acquired a next- | generation Chinese fighter, wouldn 't it be handy if someone had | the expertise to tell you exactly how its parts were made and | machine replicas if needed? | | So, the tinfoil hat interpretation of this story would be, _of | course_ the Pentagon has the original blueprints in | quintuplicate, but it 's identified reverse engineering as a key | strategic advantage China has over the US (pretty reasonable so | far, right?) and has announced this as a way to shuffle some | money into building up domestic RE expertise in the defence | industry. | [deleted] | jandrese wrote: | As someone who works with the government a fair bit, this kind | of forward thinking is extremely unlikely to be the case. This | is the kind of government competence that only exists in the | most wild conspiracy theories. | | The idea that it was made by some long defunct subcontractor | and nobody knows what happened to their blueprints and | production notes is far more likely. Also, even if you had the | blueprints you still need to be able to make the tooling, which | is at least half of this project. | | That said, if some contractor does come through with this and | does a good job (on time, on budget, parts work, etc...) they | could likely find plenty of other programs with similar needs. | In some cases the original contractor does still exist, but | they're asking way too much money to reconstitute an old | production line so a scrappy startup like this could prove | themselves valuable. | nullserver wrote: | My dad was talking to an engineer at one of the major | airlines manufactures apparently some critical part was foam | injection or some such. | | Anyway the process as such did not work as documented. | | You had to add strings to the inside of the mold to get it to | set correctly. This was not written down anywhere. | | Part of it may have been job protection. The union was bad | about that. New hires would not be able to complete the work. | | Always stuck with me that at some point the ability to make | that part would be los-tech. | pjc50 wrote: | Conversely, a lot of management have zero interest in | knowing this kind of detail. It may not be possible to get | the info fed back. People may be punished for not following | the process, even if it's impossible to get the job done by | following it exactly ( this is a very common dysfunction!) | jessaustin wrote: | Yeah this sort of "why didn't the lowest-paid employee do | more work without permission so her boss's boss's boss | wouldn't have to think too hard" suggestion surprises me | a lot more often than it should surprise me. Sure, it | would benefit shareholders, but companies are run by | executives. | hinkley wrote: | The return of guilds. | Pet_Ant wrote: | > Always stuck with me that at some point the ability to | make that part would be los-tech. | | https://www.sarna.net/wiki/Lostech | banana_giraffe wrote: | It's also possible it was "Hey! The foam injection machine | isn't working, I've tried everything", "There's this string | trick I used once, try that", "Great, that fixed it, we | should document that", "Sure, once we get all parts made | that have backed up" | | Or, maybe I'm reading bad practices in my industry to | everywhere else. | nullserver wrote: | From the conversation, admittedly 20 years ago. Not | documenting was highly intentional, and why I was being | informed. | mywittyname wrote: | It makes sense that new employees are trained on the job | from actual line workers, rather than by reading | documentation. | | It is totally possible that the line workers have no idea | what the documentation on the tooling says. | mavhc wrote: | Makes sense in the short term, but not the long term, as | the entire article makes clear | MattGaiser wrote: | I would be very interested in reading case studies where | a company both does documentation well and does not get | bogged down in vast amounts of paperwork. | | As yes, plenty of fixes for things are not written down | anywhere. | nullserver wrote: | Reproducibility. | | Have others come in and follow the directions. | jaxx75 wrote: | If you haven't read it, you'd probably enjoy (and anyone | interested in process) The Toyota Way by Liker. | MattGaiser wrote: | Thanks! | goatinaboat wrote: | _Part of it may have been job protection._ | | Management gets exactly the behaviours from employees that | it rewards and incentivises. | csours wrote: | It might have been protectionism, but also life is just | complicated. Documentation is always incomplete and much of | it is out of date as soon as you write it down. Humans have | so many cognitive biases, we don't even notice half the | things we do. | | Many scientific studies cannot be replicated either due to | errors or ambiguous steps. | | You only have what you test. If you want working | documentation, you have to do a blind test. That can be | pretty dang expensive, and most people don't think that | way. Running production is heavily motivated to just keep | running, and not worry too much about all of the potential | problems - there are just too many potential problems. | ericmay wrote: | Why does it seem to be that we always assume that our own | government is incompetent and unable of forward thinking, but | all other governments (China, etc.) are? | dylan604 wrote: | >As someone who works with the government a fair bit, this | kind of forward thinking is extremely unlikely to be the | case. This is the kind of government competence that only | exists in the most wild conspiracy theories. | | No, but we'll totally sponsor/fund research into things like | mind control and astral projection. Funding something totally | useful like reverse engineering skills is totally anathema. | Just really sad commentary | Jtsummers wrote: | > No, but we'll totally sponsor/fund research into things | like mind control and astral projection. Funding something | totally useful like reverse engineering skills is totally | anathema. Just really sad commentary | | I don't get your point. The government _does_ invest in | reverse engineering, and _much_ more than they invest into | mind control and astral projection. It 's nonsense to say | that investing in useful skills is "totally anathema". | | What GP was saying was _not_ that they don 't invest in | reverse engineering, but they wouldn't try to backdoor it | or secret the experience into the industry with some | project like this. They wouldn't try to "trick" the | industry into developing the experience by putting out | smaller contracts like this. They _do_ invest in it, but | directly. That one program office has put out a contract | for reverse engineering of one system does not mean that | the general capability is ignored, within the government or | the industry. | goatcode wrote: | >This is the kind of government competence that only exists | in the most wild conspiracy theories | | And, possibly, before the 1960s. | TheCondor wrote: | I've heard from various acquaintances that it's not unusual for | the contractor to be required to destroy documentation and | tooling for certain classified projects upon completion. | structural wrote: | It is absolutely standard practice for this to happen. At | contract completion, the contractor must destroy or return | all classified materials: these sorts of designs would | certainly be included. | | It's pretty interesting, but a lot of this stuff is | structured specifically so that the contractor organization | doesn't retain knowledge that it's "not supposed to have", as | wasteful as that ends up being. Even stuff like a list of | personnel who worked on a project or production line might be | included... so that a few years after the project is | completed, the management of the contractor might not even be | able to figure out who to ask, because they've destroyed even | their knowledge of the list of people who worked on the | component's design and manufacturing. | enkid wrote: | Read about the history of NASIC and the other service | intelligence centers [0]. Understanding foreign technology is | one of their core missions. I'm pretty sure they have already | been reverse engineering stuff for a long time. | | [0]https://www.nasic.af.mil/About-Us/Fact- | Sheets/Article/611728... | time0ut wrote: | I don't think we need the tinfoil hat. This sort of thing | happens sometimes. Like the time we forgot how to may part of | our thermonuclear weapons and had to reverse engineer that [0]. | | 0 - https://en.wikipedia.org/wiki/FOGBANK | tablespoon wrote: | > I don't think we need the tinfoil hat. This sort of thing | happens sometimes. Like the time we forgot how to may part of | our thermonuclear weapons and had to reverse engineer that | [0]. | | The really interesting thing about that is one of the main | things they had to reverse-engineer was an _impurity_ in one | of the ingredients that the original designers didn 't even | know they were depending on. | est31 wrote: | Reminds me of how NASA had to design completely new rocket | engines for SLS because while they still had the plans for | the Saturn-V rocket engines, back then plans weren't | followed to such high accuracy as nowadays a 3D model would | be followed. Each engine was custom tailored with small | modifications here and there. The knowledge to custom | tailor them was lost, so they went with designing new | engines from scratch instead. | | https://www.youtube.com/watch?v=ovD0aLdRUs0 | KineticLensman wrote: | > Each engine was custom tailored with small | modifications here and there | | This was true of lots of things outside NASA. This was | one of the problems that killed the UK attempt to | modernise the Nimrod maritime patrol aircraft [0]. They | wanted to fit new wings to the old planes, but only | discovered after the contract had been signed that the | different airframes had not been built identically, but | were different interpretations of a common plan. Each of | the nine planes was in effect a completely new refit | challenge. | | [0] https://en.wikipedia.org/wiki/BAE_Systems_Nimrod_MRA4 | subsubzero wrote: | I was going to comment about fogbank as well, this article | explains the efforts the Govt. tried to reverse engineer the | substance - https://www.washingtonexaminer.com/weekly- | standard/the-fog-o... | | Also it is no longer known how to make the Saturn V rocket | which flew to the moon - | https://www.nytimes.com/1987/05/26/science/hunt-is-on-for- | sc... | cratermoon wrote: | Wikipedia calls it an "aerogel", but rumors have it | originally being closer to ordinary "closed-cell extruded | polystyrene foam", which is often sold under the brand name | Styrofoam. It might be something else entirely now. It's role | is said to be absorbing the x-rays generated by the fission | stage and turning into a plasma to help ignite the fusion | stage. Edit: | https://www.armscontrolwonk.com/archive/201814/fogbank/ | mattnewton wrote: | I wish my tax dollars were going to some galaxy-brain forward | thinking group of men and women capable of making such reverse | engineering challenges for itself; but it almost certainly is | the case that what looks like sheer incompetence is just that. | prox wrote: | Most of the companies are Initech ;) | tablespoon wrote: | I don't think this kind of thing is all that uncommon for | military airplanes that have been long out of production. I | recall reading a decade or two ago that our local air guard | wing had to fabricate some of its own replacement parts for its | F-16s (IIRC, then some of oldest that were still in service). | | I also recall that Lockheed had to take special effort to | preserve production know-how and tooling for the F-22 when they | shutdown production early, so it would be _possible_ to restart | if needed. You can 't capture everything you need to know in | blueprints and documentation. | benzene wrote: | >Long out of production. | | The difference in technology likely plays a large role - | these parts were designed without CAD and modern fabrication | protocols have changed. | | It reminded me of NASA's endeavor to reverse engineer the | Saturn rockets | | https://arstechnica.com/science/2013/04/how-nasa-brought- | the... | [deleted] | hondo77 wrote: | > The difference in technology likely plays a large role - | these parts were designed without CAD and modern | fabrication protocols have changed. | | Actually, the B-2 was one of the first military aircraft | designed with CAD. | | https://www.northropgrumman.com/wp- | content/uploads/B-2-Spiri... | | (search for "NCAD") | jyounker wrote: | Preventing the loss of manufacturing capability is one of the | reasons for offering military aid to friendly countries. We | give them money to buy weapons, but they are obligated to buy | certain weapons systems with that money. | | For example, the Saudi's really don't need all those M-1s | they buy from us (with money we give them), but we offer the | it keeps our production lines open and active. | | It's a devious way of laundering military readiness expenses. | godelski wrote: | Even if you're not innovating everything you want to reverse | engineer enemy systems because you want to discover | vulnerabilities. This is common practice. | Jtsummers wrote: | US DOD and their industry partners definitely has this | capability already. If they're putting this call out there then | there's a real need, not a covert effort to promote the | discipline of reverse engineering. | AnthonyMouse wrote: | Also, to quote Independence Day: | | > You don't actually think they spend $20,000 on a hammer, | $30,000 on a toilet seat, do you? | | The budgets they use for secret reverse engineering aren't | booked as any kind of reverse engineering. | jessaustin wrote: | One fears we'd be shocked by how much is actually going to | General Smith's brother-in-law's toilet-seat dropship | company. We'd like to think that Pentagon auditors could | find that sort of thing, except that Pentagon people tell | us continuously that they are _unauditable_. | | https://www.thenation.com/article/archive/pentagon-audit- | bud... | magtux wrote: | This happens even outside Defense in all specialized industry. I | was once asked if I could reverse engineer a part for a 30 year | newspaper stacking machine in a printing press. Very interesting | stuff and a consequence of being niche. | starpilot wrote: | Also in auto repair. A shop told me they wanted to take a | gasket from the engine, draw the part, then send it to a | machine shop to have it fabricated. | [deleted] | pvarangot wrote: | Large scale printing machine setups are insane. I've seen very | old installations go for prices that are higher or comparable | to a new setup just because you know the throughput and you | know the civil engineering is sound. | foobarian wrote: | Try most web companies :) I'm a week into reverse engineering | ancient URL canonicalization at my new place... sigh | Jtsummers wrote: | Exactly. We're dealing with: | | - Limited production run. These aren't Ford Mustangs or Toyota | Priuses with hundreds of thousands and millions being produced. | There were 21 built over 13 years. This also leads to the | consequence that each one should be considered a bespoke | creation and not a "copy" of the others (even ignoring the 20+ | years of individual maintenance work they've each had). | | - Time. It's been 21 years since the last one was produced in | 2000. Whatever facility produced this has long since lost that | capability. | | - Aging workforce. Whoever designed it is likely retired, and | could even be dead at this point. Certainly the senior | engineers who may have been 40+ when the project started in the | 70s/80s. Even if they weren't retiring and dying, the people on | the project have been doing other things for 20+ years. | lambda2001 wrote: | The last part is extremely true. I have known many engineers | that worked on the B-2 and have since retired. There's very | little chance many of them would come out of retirement and | honestly I don't think the government would pay for that. | azernik wrote: | And even if they did, no one remembers that well the things | they did decades ago. | whalesalad wrote: | The B-2 is ancient, doesn't seem very surprising. | Voloskaya wrote: | It is by no mean ancient. | | The introduction of the B-2 in service was ~24 years ago, this | is one of the most recent jet in the US air force. By military | standard it's definitely young. | | There are only 2 planes in service in the US more recent than | that, the F-22 and F-35 (not counting transport aircrafts). | | Those planes are designed for lifespans of 50-100 years. | whalesalad wrote: | My dad was at the Skunk Works for 20 years. He then went on | to work at Northrop for a good chunk of time as well. | | The B-2 was started in the 70s and the maiden flight occurred | while I was still baking in the womb. | | I realize aircraft can live a long time and can be | retrofitted and upgraded with modern technology - but all | things considered it is old. | | Not saying ancient is bad, either, but as far as | organizations go, org knowledge, handoffs of info and books | and writing etc... I am not surprised to see the need for | reverse engineering. | Daho0n wrote: | It first flew 31 years ago. If that is ancient what is the F-16 | that first flew 49 years ago? | Jtsummers wrote: | I had to check, it's not as ancient as some other bombers with | B-2 first flight occurring in 1989. I met a pilot who flew on | the same B-52 as his father, and his grandfather had flown some | of the first B-52s. This was in the 00s, about 15-18 years ago. | aphextron wrote: | It's impossible to overstate how long these things have been | in service. The oldest B-52 airframes still in active service | were built longer ago than the first flight of the Wright | brothers was when they were built. | rstupek wrote: | And likely to be in service for another 30 years. A 100 | year airframe | [deleted] | feralimal wrote: | Yes, as the US cedes the economy to China, they will also surely | become stronger militarily. And with the US (and other Western | countries) in a perpetual lockdown in the coming years, which | will accelerate the transition - we had better make sure we are | able to copy the tech! | flyinghamster wrote: | This brings up an important principle: the higher the tech, the | shorter its lifespan. A cellphone from the 1980s won't function | anywhere but in a Faraday-caged lab equipped with a suitable cell | site, while 2G and 3G systems are fast disappearing. Only | recently have landline telephone exchanges begun to drop support | for pulse dialing, but otherwise, a rotary-dial desk phone from | 100 years ago would still work today, and DTMF dates to 1963. | projektfu wrote: | I read once that if you tried to build WWII-era aircraft | according to specs and mechanical drawings, they wouldn't fly. | The real design was found in the dies and jigs that were adapted | after many iterations and test flights. | Qw3r7 wrote: | You might have fitting issues with what I like to call "slide | ruler error". | | How things came to be and are, are often at times not | documented. Dimension and tolerancing is lost over time too. | LeonenTheDK wrote: | That's an interesting though, like software documentation that | hasn't been updated over years of patches. | | Do you remember where you read that? Sounds like an interesting | bit of history. | birdyrooster wrote: | Also sounds like a git repository where people were working | on local branches to do production work and then when they | left the company, never pushed their branch upstream. | kelchm wrote: | That's assuming there is a git repo or any kind of version | control at all. | oehtXRwMkIs wrote: | They're not assuming. They're analogizing. | azernik wrote: | A long write-up of an equivalent for the F-1 engine is here: | https://arstechnica.com/science/2013/04/how-nasa-brought- | the... | | The analogy to out-of-date software documentation is very | apt. As problems or inefficiencies popped up in the factory, | they'd change things and just not write them down (because of | deadline pressure, often). If you wanted to build new ones | you'd have to either get the factory workers to show you how | the thing was _actually_ built, or tear down a working | example to reverse engineer it. (Which has been done!) | tpmx wrote: | I only worked tangentially in the field, but I get the feeling | that modern semiconductor manufacturing is sort of the same, | except with more excel sheets and the like? | smhinsey wrote: | If you find this stuff interesting, pick up a book aimed at | hobbyist metal lathes. Just reading a little about how you set | up a tiny home version can give you a whole new level of | understanding and respect for this kind of stuff. Structural | components are different but in that era and even to some | extent today, most precision parts were machined with two | primary tools: the lathe and mill. Today both would be CNC and | you'd add other modern tools but the CNC lathe is still a lathe | and they work the metal in the same fundamental way. | | Due to the dispersed mass production in WW2 it's probably not | totally true that they wouldn't fly without a custom tooling | setup (it'd be a maintenance nightmare if two examples of the | same model from different plants diverged dramatically, altho | of course it happened) but you can be certain that it's of | critical importance. | Aeronwen wrote: | It's because the designs weren't made for mass production. | The given tolerances were nominal and you were supposed to | hand-fit parts together. | | For mass production, they had to be re-tooled with larger | tolerances which also allowed for interchangeable parts. | elevaet wrote: | The only possible explanation is that the Stealth Bomber was | indeed crafted using alien technology. /s | lurquer wrote: | For many reasons - limited production run, secrecy, and age -- | the need in this case for reverse engineering isn't all that | surprising. | | Nevertheless, these things may become more common if we are at | the apex of our civilization. | | I could imagine a RFP in Rome from 300 AD or so soliciting bids | to figuring out how the hell to make an aquaduct, amphitheater, | or even cement! | YesThatTom2 wrote: | Why is the government allowed to reverse engineer AND create laws | making it difficult for citizens to do so? | | Obviously the answer is that it is legal to reverse engineer | something if you own it. | | That said... I think there's an opportunity here: | | EFF and other pro-reverse engineering organizations should sue | and demand that the DOD follow the same laws that citizens | follow. | | If they lose the lawsuit, it be great ammunition (so to speak) | for stopping anti-reverse engineering laws. | | If they win... bonus! | macspoofing wrote: | >Obviously the answer is that it is legal to reverse engineer | something if you own it. | | Or the contract allows it. | Jtsummers wrote: | > EFF and other pro-reverse engineering organizations should | sue and demand that the DOD follow the same laws that citizens | follow. | | They'd have to have standing for such a suit and they have | none. NG and others involved in the design and manufacturing | might have standing, but they're also unlikely to sue. This is | not a novel activity for DOD. | [deleted] | mgarfias wrote: | Somethign I haven't seen mentioned here is that the technology | used to design this thing is waaaaaaaaaaaay old. I know for a | fact it was designed on an IBM mainframe (dad ran the one that | the YF-22 was designed on). I can't remember what CAD package | they used there, but its definitely conceivable that the software | doesn't even exist anymore. How would you go about building a new | one if you can't read the CAD files, if you have them. | | Hell, the building in hawthorne where dad worked isn't even owned | by northrop anymore. Its spacex. | folli wrote: | Reverse engineering the files night be easier than reverse | engineering the airplane. | curiousllama wrote: | Says the guy not constantly surrounded by aerospace engineers | :) | | What are the odds someone said the phrase "those parts? I | could mock up copies in a weekend!" | rlyshw wrote: | I've done installs of video streaming tech on USAF-managed NIPR | net and we've had to reverse engineer some of the mechanisms on | their own network... This does not surprise me at all. | ed25519FUUU wrote: | > _... Air Force's Rapid Sustainment Office (RSO) was looking to | industry for a "cutting-edge, automated 3D scanning system," | specifically intended to replicate aircraft parts that are no | longer in production, including at maintenance depots._ | | You see the real issue? Even if they have the blueprints, it will | be _difficult_ to even manufacture the parts here. | | There's so many more problems like this coming down the pipeline. | We've effectively lost (or rather acquiesced) almost all | manufacturing skill to other countries. This was a result of the | largest corporations taking advantage of labor arbitrage and then | flooding their home market out of business. | | If we really want to reverse this, we need to do what it takes to | bring manufacturing back to the United States. It's a painful | reversal of the open-trade policies of the past. Honestly, Trump | was right to fight so hard for this, even going so far as to | remove us from NAFTA. | | I don't have a good strategy for this, but probably some set of | minimum manufacturing of _everything_ should happen within our | borders, say 10%, and accomplishing that target with a | combination of sticks and carrots. | wwww4alll wrote: | Unfortunately, your assessment is very correct. There will be | no solution and only a slow decline as previous systems become | obsolete and there no on to fix or upgrade to better systems. | | This country is producing more Tik Tok stars than engineers | that can sustain civilization. | austinshea wrote: | What a confident proclamation that is backed up by nothing, | aside from your limited perspective. | wwww4alll wrote: | Name a successful plane developed recently by US military | or commercial enterprises? | robotnikman wrote: | IIRC military hardware (ships, tanks, aircraft, etc) is | required by law to be manufactured within the country, for | obvious reasons. | | Its some of the little manufacturing the country has left | Daho0n wrote: | Yet just landed on Mars, bringing a helicopter. Please don't | spread FUD. | ed25519FUUU wrote: | How much of the spacecraft was _manufactured_ in the USA? Are | we able to create another one without our trading partners? | 1996 wrote: | I don't understand why you are getting downvoted. | | Being unable to manufactures things we did in the past is | extremely worrying | wwww4alll wrote: | Unfortunately, this will result in failure. | | This country simply does not have enough skilled engineers to | design and produce original parts to requirements. Let alone | reverse engineer a worn out part. | | B2 is product of its time and the amount of engineering resources | that went into design and development simply can not be | replicated with current society. | | Tik Tok stars make multi millions of dollars, so why would any | smart person spend years in school and solve complex problems to | build state of art Stealth Plane. | | Boeing can't even produce a simple jet without having it fall out | of the sky few times, 737 Max. | lambda2001 wrote: | I would disagree on this point. I work in aerospace with a a | lot of smart folks. Boeing's 737 issues are a product of many | years of poor management choices, but I don't think represent | the talent of the industry as a whole. | wwww4alll wrote: | 737 Max is just the poster child for issues in aerospace. | There are many other examples, F35, 787, F22, are just recent | examples. | | The flow of smart folks in the pipeline are dwindling. You | may be working with smart folks, but how many are going to | retire in few years? Who are going to replace them? Does the | current education system produce the number and quality of | candidates needed? | aarongray wrote: | Proof the B-2 was built using UFO technology :-P | azernik wrote: | A related story: | | One of the proposals for future upgrades to SLS (ugh) was liquid- | fueled boosters using new-build F-1 engines (i.e. Saturn V main | engines). Unfortunately, the specs were not complete; not only | was lots of stuff different in the factory than in the drawings, | but parts of the engine were literally hand-built. Think API | documentation built on a tight deadline, and published while | software is still under development. | | Luckily, some NASA engineers were already taking one apart and | modeling the parts for previous SLS work. The new Dynetics | version ended up much simpler and cheaper because of new | manufacturing methods, but the reverse engineering process | required to get there was a serious project in its own right. | | https://arstechnica.com/science/2013/04/how-nasa-brought-the... | kgbier wrote: | Here is a relevant lecture on the decay of specialised knowledge | across civilisations. | | https://youtu.be/ZSRHeXYDLko | | Included is an anecdote about Texas Instruments and loss of | knowledge between generations of silicon hardware. | mschaef wrote: | The US nuclear weapons program had to do something similar in the | 2000's with a material known as Fogbank. This is used in the W76 | warhead as an interstage material, and they needed more of it to | keep the weapons in operational state. | | Unfortunately, they'd forgotten the manufacturing process, | decommissioned the plant that made it, and the people that knew | how to do it weren't around any more. They figured it out, but it | doesn't necessarily look easy to do (nor does the material seem | easy at all to make in the first place). | | https://www.armscontrolwonk.com/archive/201814/fogbank/ | | p20 here says more: | https://www.lanl.gov/science/weapons_journal/wj_pubs/17nwj2_... | | Edit: I somehow missed this other thread in this story, despite a | search: https://news.ycombinator.com/item?id=26334367 | [deleted] | workergnome wrote: | My grandfather spent the last part of his career doing this sort | of work--often on classified projects, I'm told. Usually there | was an assumption made on the project about the useful working | life of any part, and the expected duration of the program, and | they made the "right" number of spares. | | Things change, and the factory/tooling/people are long gone. | Also, often the underlying tech isn't available. But the part | needs to weigh the same amount, meet the same guidelines, and fit | in the same hole. | | It's cheaper to pay someone to spend the time to figure out how | to make the replacement then to mothball the entire airplane-- | almost regardless of how expensive it might be. ___________________________________________________________________ (page generated 2021-03-03 23:00 UTC)