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> This offense is unique in that it was neither motivated by greed nor any desire for personal enrichment. How... What? What was it motivated by, if not to sti

• tyingq 5y ago
  "she thought it was "stupid" that the Navy required the tests to be conducted at -100F (-70C)" I'd be curious to know what that requirement is for too, though I'd likely not just ignore it.
  • newacct583 5y ago
    Which is sort of the same thing. "I don't want to run this expensive or complicated test because it's stupid" is certainly a kind of cost cutting.
    • tyingq 5y ago
      Maybe, but not necessarily. I bet many of us paper over requirements we think don't add value, where we can get away with it. Solely because we think it adds no value.
      • alistairSH 5y ago
        While both might be illegal, there's a massive difference between papering over a requirement for a business application and papering over a requirement for a mechanical specification. The former might cost a customer money; the latter puts lives at risk.
        • tyingq 5y ago
          >the latter puts lives at risk Maybe. There are certainly past cases of the military creating unreasonable/unhelpful specifications. Edit: Not justification for what she did. Just curiosity, having spent a fair amount of time in the military.
          • NikolaeVarius 5y ago
            It is not the job of an individual to simply just ignore a spec instead of bringing up a complaint.
            • tyingq 5y ago
              Yes, I'm not justifying what she did. I am, however, curious if the requirement was "stupid" or not.
              • NikolaeVarius 5y ago
                There is always a chance it is, however without some deep knowledge on the reasons for the spec, its impossible to say why a spec exists in the first place. Many of these large scale engineering specs are "take the worst possible situation you can ever think of and design it so that it can survive 1.3x of that". Yes it sounds stupid to the layman, but this is how you make shit that survives everything you toss at it. Ignoring "dumb specifications" is the reason why SpaceX lost a payload. They used non aeronautical grade metal, which did not conform to the requirements for spaceflight, causing a mission failure.
      • NikolaeVarius 5y ago
        Anyone who would paper over requirements that involve lives is a terrible engineer and should be blacklisted from anything resembling engineering.
    • QuarterReptile 5y ago
      It probably significantly improved her return on brain damage.
    • capitainenemo 5y ago
      According to other coverage it was not a failure to run the tests, it was changing failed grades to passes. https://www.wavy.com/news/military/navy/metallurgist-faked-steel-test-results-for-navy-subs-for-decades/ https://www.wavy.com/news/military/navy/metallurgist-faked-s...
  • Nasrudith 5y ago
    I don't know about how cold deep artic waters may be (I doubt that much), but strength-stress curves are likely why. The easiest way to make something last long and not have unexpected accidents is to overrate it big time - such that any wear would need to become blatant. To take an ergonomically silly exampke shovel handle could be a three inch diameter of solid steel that can take five metric tons per square centimeter as pressure without bending. If it wears out enough that it could snap by human body weight it would have to be worn quite a bit.
    • jhgb 5y ago
      Salt water won't go much below zero. At oceanic salinity levels I doubt there's any place with liquid water below -2C.
      • soco 5y ago
        Submarines don't stay all the time under water.
        • jhgb 5y ago
          They're designed to spend as much time under water as possible (i.e., months, basically). That's the whole reason for nuclear power on submarines.
          • soco 5y ago
            The official requirement of the US Navy seems to disagree and I tend to trust they know better than us what they design their gadgets for. The metallurgist also thought they knew better, because they're operating submarines for their lives... oh wait.
            • jhgb 5y ago
              We have no knowledge of what those castings were used for. It's impossible to judge whether the requirement for these parts was excessive/copy-pasted, or not, and if it was, then by how much.
  • cmurf 5y ago
    South pole mean winter low is -76F but -128F has been recorded. While the water isn't going to get that temperature, subs need to surface periodically. I bet they've looked at the probability of needing the ability to operate in extreme cold, and -100F is the compromise.
    • tyingq 5y ago
      I had assumed the tests were related to pressure and depth, where the temp isn't much off of 0C. Not an area of expertise for me though.
    • LeifCarrotson 5y ago
      A submarine cannot surface at the south pole.
      • simcop2387 5y ago
        Yet. Give it time. Though, i believe they just meant the waters surrounding Antarctica.
        • VistaBrokeMyPC 5y ago
          Yet? There's land underneath the ice at the south pole.
          • sfifs 5y ago
            I believe yet refers to https://www.sciencealert.com/scientists-think-earth-s-next-supercontinent-might-look-like-one-of-these https://www.sciencealert.com/scientists-think-earth-s-next-s...
    • yodon 5y ago
      I used to design and build scientific equipment for the South Pole. We had to do all our own materials testing because manufacturers would only specify their products to the bottom of the MILSPEC temperature range and the South Pole goes below that. I remember one spool of cabling in particular - it was beautiful stuff, highly flexible, high current carrying, just what we needed. It stayed awesome right to the bottom of the milspec temperature range, at which point the exterior sheathing went through some kind of phase transition and froze solid, followed by the interior insulation having a different coefficient of thermal expansion than the exterior sheathing resulting in the whole thing shattering itself into pieces just a few degrees below military operating temperatures.
  • ortusdux 5y ago
    There are plenty of things to control for when designing and producing steel. An important consideration for some applications is the brittle to ductile transition temperature. Some steels have a DBTT around 0­°C, which means that they loose most of their impact resistance below that temp. By adjusting the chemistry, processing methods, and post-processing methods, you can adjust the DBTT of steel down below -70°C. My guess is that they were being paid to supply steel with a DBTT below -70°C, and that the contract included proof testing. The standard testing method would be a Charpy impact test at various temperatures. It sounds like they were making complex castings, so they probably had some non-standard testing requirements. More info: https://www.punchlistzero.com/dbtt-ductile-brittle-transition-temperature/ https://www.punchlistzero.com/dbtt-ductile-brittle-transitio... https://knifesteelnerds.com/2018/12/21/why-cold-steel-is-brittle/ https://knifesteelnerds.com/2018/12/21/why-cold-steel-is-bri...
    • tyingq 5y ago
      So sounds like designing for surface collisions (other vessels, icebergs) in a very cold area maybe?
      • ortusdux 5y ago
        The Navy is understandably cagey about how they surface through ice-sheets, but this Smarter Every Day video is the best summary I have seen. https://youtu.be/XFJnWp1tAdU https://youtu.be/XFJnWp1tAdU Basically, some part of the sub needs to be strong enough to reliably break ice at sub-zero temps. The rest needs to maintain its strength at those temps.
      • jeffdn 5y ago
        Yes, U.S. Navy nuclear submarines go under the polar ice caps somewhat frequently -- as did Soviet (and do Russian) nuclear submarines as well. It's a good place to hide from prying eyes, as not only can ships not (easily) follow you there, but the sound produced by all the ice moving and grinding makes passive sonar quite ineffective. The YouTube channel Smarter Every Day recently had a video series on a nuclear submarine under the arctic ice.
  • jjk166 5y ago
    Likely it has to do with the scaling of the actual property being measured. For example with decreasing temperature, steels become less and less able to resist impact damage. Thus getting hit by something small at cryogenic temperatures is equivalent to being hit by something big at normal temperatures; so if you want to test whether a submarine can survive an impact that would be impractical to simulate in a lab, you could instead cool your test sample down a lot and test it with a smaller, cheaper device. My knowledge of shipbuilding is limited but I believe the navy suffered quite a bit during WW2 from certain steels undergoing a transition in the low temperatures of the north atlantic that caused brittle fracture. I would imagine testing at ultra low temperatures accelerates the rate at which such brittle fractures can be detected.
  • belorn 5y ago
    It would be interesting to know how cold the ballast tanks (and connected pipes) gets when the compressed air get released. Air going from high pressure to low can quickly drop the temperature, especially if its already at a fairly low point to start with.
  • s1artibartfast 5y ago
    IT is entirely possible the requirement was stupid, over-specified, and irrelevant, but that is beside the point.
  • albrewer 5y ago
    Brittle fracture toughness for carbon steels (resistance to cracking) gets really bad below about -20 °F. The colder you get, the more things you have to do to keep that toughness up, or else steel will crack like cast iron instead of bending and stretching like it's supposed to. I come from the pressure vessel industry where impact testing is routinely required at temperatures below -20°F, sometimes at -320 °F for cryogenic applications. Fracture mechanics and low temperature behavior of steels is a relatively "new" field in engineering, only emerging sometime in the last 80 years, so I can see why the metallurgist may not have known too much about it. Widespread study was kicked off in the US with the Liberty ship disasters: https://metallurgyandmaterials.wordpress.com/2015/12/25/liberty-ship-failures/ https://metallurgyandmaterials.wordpress.com/2015/12/25/libe... If you want to know more about stuff like that, ask away; it was far and away the most interesting part of my mechanical engineering education and career before I switched over to tech :)
• Nasrudith 5y ago
  Sloth perhaps and seeking the path of least resistance? If they receive no sales commission just check the box and get it done and them out.
  • capableweb 5y ago
    If it was a random employee, then I'd agree with you that it would be possible. But she is/was the director of metallurgy at the foundry, so hard to remove her from any responsibility.
• aritmo 5y ago
  Indeed, it's a very silly statement. As if the specific requirement was not meant to be taken literally but the metallurgist should abide to it anyways. The metallurgist just wanted to save some $$$ by selling rejected/out-of-specs products.
  • Narretz 5y ago
    That's a giant leap in logic. She wouldn't even save money, the company would. I doubt this was the only test they did on the steel. It might have been that from her perspective she got the same steel over and over again, and just didn't do the work, because she was lazy.
• hacknat 5y ago
  It sounds like it was motivated by laziness.
  • LeifCarrotson 5y ago
    I've operated environmental testing chambers for automotive customers. It's comparatively quick and easy to do the +85C high-temperature testing, but it takes a long time and/or an expensive, oversized refrigeration unit for a chamber and the parts in it to reach the target -40C/F low temperature. -70C/-100F would probably take a very, very long time. Even in the brutally suspicious automotive industry, it's common to have an operator manually copy the chamber temperature or thermocouple reading to the test report. Especially if you believed that the test requirement was excessive, there would certainly be a temptation to lie and say that the temperature had reached the target. I wonder how the lie got discovered. Did her successor notice that they were less productive than she had been, because the chamber was slower than what she claimed it could do? Was the chamber incapable of reaching the target temperatures? Did the measured test results come out different?
  • capitainenemo 5y ago
    Other coverage says the tests were run, but fails were reported as passes. https://www.wavy.com/news/military/navy/metallurgist-faked-steel-test-results-for-navy-subs-for-decades/ https://www.wavy.com/news/military/navy/metallurgist-faked-s...
• didntknowya 5y ago
  sometimes people are just lazy
  • capableweb 5y ago
    Then you would just say "No, I won't do that, we can't offer you this service/product" instead of "Yes, I will do that, pay us and we make it happen", and then don't do it.