4 ms·

My first job out of college was working for the navy as a civilian engineer. At the time I read through all these and found them on par with the education I got

My first job out of college was working for the navy as a civilian engineer. At the time I read through all these and found them on par with the education I got at my university. With the training found in these books a sailor could understand and repair almost any analog system on the ship. They did not keep up this training for the digital age, and its a shame because on a modern naval ship almost everything is done via computer control and the current training is swap out the digital parts if anything breaks.

vonmoltke 6y ago
> They did not keep up this training for the digital age, and its a shame because on a modern naval ship almost everything is done via computer control and the current training is swap out the digital parts if anything breaks. I have a fair bit of experience with this from the civilian contractor side. The main problem with these modern Line Replaceable Modules (LRMs) and Line Replaceable Units (LRUs)[1] is that they require specialized tooling and equipment to properly troubleshoot, repair/rework, and test. They also each require some parts that are specific to the LRM/LRU. Shipboard technicians could be given the training to do the work (mostly), but there would be no space for all the other physical elements required to actually do it. At first the DOD pushed all this back on the contractors (any failed LRM/LRU was shipped back to the factory), but when I left that world they were moving towards a model where branch depots could receive the failed LRM/LRU, test it, and perform basic repair/rework without contractor intervention; they would only ship the hairy cases back. That's about as good as they can get, because it just in feasible or cost effective to spread that capability out to every base and ship around the world. [1] Those are Air Force terms, but the Navy as similar concepts.
- jki275 6y ago
  Navy CVNs have micro miniature repair shops onboard, and no Depot level repairable leaves the ship without screening by them to see if they can repair it. They have a significant incentive to do so, as the money they save is something they can take credit for, and the ship's budget is significantly helped out by their repairs.
  - dkhenry 6y ago
    Here is what I saw with both this and the Parent's comment about LRU's, and this is in the context of the CVN's where I did my work. Every vendor uses something different ( count how many flat panel computer model's are on a CVN ) so instead of being able to swap the hard drives or PSU on a embedded PC you throw the whole thing out and replace it. Same goes for most control hardware. There may be dozens of independent control systems using pretty much every vendor of controller. I would love to see the IC's be able to rebuild any control system underway and re-program it, like they could do with the old analog based systems.
    - jki275 6y ago
      Oh, nobody would be repairing flat screen monitors (though I replaced CRTs while I was in), but get into radars and fire control systems and servos and such and those definitely get repaired onboard. When the choice is replace a 50 cent resistor or send the module off and wait six months for a spare that costs the ship half a million bucks, you better believe people get the job done. I owned the 2M shop on a CVN for a while. We repaired millions of dollars worth of equipment.
  - jkhdigital 6y ago
    I still list a bullet point on my resume of the approximate dollar value of all the equipment I repaired myself during the ~3 years I was stationed in the calibration lab on a CVN. My favorite is the $20k precision power sensor standard that I troubleshooted down to a single transistor which cost a couple bucks to replace. I’ll add that on my ship, the “screening” you speak of was most often performed by the cal lab, since we were the only ones trained in component-level repair on general electronics. The 2M shop just did the soldering for us ;-)
    - jki275 6y ago
      LOL, the constant AT/ET rivalry.
    - rwmurrayVT 6y ago
      And that's how you retire and go to work at an AIT :-)
jki275 6y ago
Ah but they did! The Data Systems rate covered the digital age up into the late 1990s (there's a series of books for them too -- I was able to find one of them in public view at least[0]). The DS rate did everything from gate level troubleshooting of Navy computers to machine language programming and networking and more conventional IT sorts of things. Unfortunately, the DS rate was decommissioned in 1998 and the vast majority of their responsibilities were shifted over to the FC and ET rates. There was also a DP (Data Processing Technician) rate, which eventually combined with the Radioman rate to become the IT (Information Technician) rate. They're now generally in charge of all Navy computing shipboard. [0] https://babel.hathitrust.org/cgi/pt?id=uiug.30112105115379&view=1up&seq=3 https://babel.hathitrust.org/cgi/pt?id=uiug.30112105115379&v...
saltcured 6y ago
My father taught and did some curriculum development for the Navy electronics school in the 1960s. His prior work out in the fleet was cited for its high quality. His old stories of studying schematics, rebuilding radar repeaters, and performing occult rituals around wave guides seem hard to transplant to a world of synthetic apertures and DSPs. Similarly, I think cryptography tech was then just transitioning from complex piles of discrete components into things more like modern computers full of integrated circuits. As integrated circuits and software eats the world, I think there is less opportunity for a technician in the field to diagnose and correct a problem in the functional paths of such systems. There might be important field-work remaining in the power electronics and environment of the digital systems, but it isn't surprising to me that larger black boxes become the replaceable units. You replace an entire unit with something in-spec. If the software needs tuning, that is going to happen back in a lab somewhere and come out as a new revision of a system, not happen in the field like someone patching a faulty wiring harness.
- madengr 6y ago
  SAR still uses waveguide arrays. My advisor did a lot with SAR in the 60’s, of course it was all analog and optical processing, but you could still get a real-time image to strips of film.

vonmoltke 6y ago

> They did not keep up this training for the digital age, and its a shame because on a modern naval ship almost everything is done via computer control and the current training is swap out the digital parts if anything breaks. I have a fair bit of experience with this from the civilian contractor side. The main problem with these modern Line Replaceable Modules (LRMs) and Line Replaceable Units (LRUs)[1] is that they require specialized tooling and equipment to properly troubleshoot, repair/rework, and test. They also each require some parts that are specific to the LRM/LRU. Shipboard technicians could be given the training to do the work (mostly), but there would be no space for all the other physical elements required to actually do it. At first the DOD pushed all this back on the contractors (any failed LRM/LRU was shipped back to the factory), but when I left that world they were moving towards a model where branch depots could receive the failed LRM/LRU, test it, and perform basic repair/rework without contractor intervention; they would only ship the hairy cases back. That's about as good as they can get, because it just in feasible or cost effective to spread that capability out to every base and ship around the world. [1] Those are Air Force terms, but the Navy as similar concepts.

jki275 6y ago
Navy CVNs have micro miniature repair shops onboard, and no Depot level repairable leaves the ship without screening by them to see if they can repair it. They have a significant incentive to do so, as the money they save is something they can take credit for, and the ship's budget is significantly helped out by their repairs.
- dkhenry 6y ago
  Here is what I saw with both this and the Parent's comment about LRU's, and this is in the context of the CVN's where I did my work. Every vendor uses something different ( count how many flat panel computer model's are on a CVN ) so instead of being able to swap the hard drives or PSU on a embedded PC you throw the whole thing out and replace it. Same goes for most control hardware. There may be dozens of independent control systems using pretty much every vendor of controller. I would love to see the IC's be able to rebuild any control system underway and re-program it, like they could do with the old analog based systems.
  - jki275 6y ago
    Oh, nobody would be repairing flat screen monitors (though I replaced CRTs while I was in), but get into radars and fire control systems and servos and such and those definitely get repaired onboard. When the choice is replace a 50 cent resistor or send the module off and wait six months for a spare that costs the ship half a million bucks, you better believe people get the job done. I owned the 2M shop on a CVN for a while. We repaired millions of dollars worth of equipment.
- jkhdigital 6y ago
  I still list a bullet point on my resume of the approximate dollar value of all the equipment I repaired myself during the ~3 years I was stationed in the calibration lab on a CVN. My favorite is the $20k precision power sensor standard that I troubleshooted down to a single transistor which cost a couple bucks to replace. I’ll add that on my ship, the “screening” you speak of was most often performed by the cal lab, since we were the only ones trained in component-level repair on general electronics. The 2M shop just did the soldering for us ;-)
  - jki275 6y ago
    LOL, the constant AT/ET rivalry.
  - rwmurrayVT 6y ago
    And that's how you retire and go to work at an AIT :-)

jki275 6y ago

Ah but they did! The Data Systems rate covered the digital age up into the late 1990s (there's a series of books for them too -- I was able to find one of them in public view at least[0]). The DS rate did everything from gate level troubleshooting of Navy computers to machine language programming and networking and more conventional IT sorts of things. Unfortunately, the DS rate was decommissioned in 1998 and the vast majority of their responsibilities were shifted over to the FC and ET rates. There was also a DP (Data Processing Technician) rate, which eventually combined with the Radioman rate to become the IT (Information Technician) rate. They're now generally in charge of all Navy computing shipboard. [0] https://babel.hathitrust.org/cgi/pt?id=uiug.30112105115379&view=1up&seq=3 https://babel.hathitrust.org/cgi/pt?id=uiug.30112105115379&v...

saltcured 6y ago

My father taught and did some curriculum development for the Navy electronics school in the 1960s. His prior work out in the fleet was cited for its high quality. His old stories of studying schematics, rebuilding radar repeaters, and performing occult rituals around wave guides seem hard to transplant to a world of synthetic apertures and DSPs. Similarly, I think cryptography tech was then just transitioning from complex piles of discrete components into things more like modern computers full of integrated circuits. As integrated circuits and software eats the world, I think there is less opportunity for a technician in the field to diagnose and correct a problem in the functional paths of such systems. There might be important field-work remaining in the power electronics and environment of the digital systems, but it isn't surprising to me that larger black boxes become the replaceable units. You replace an entire unit with something in-spec. If the software needs tuning, that is going to happen back in a lab somewhere and come out as a new revision of a system, not happen in the field like someone patching a faulty wiring harness.

madengr 6y ago
SAR still uses waveguide arrays. My advisor did a lot with SAR in the 60’s, of course it was all analog and optical processing, but you could still get a real-time image to strips of film.