navy

11 Articles

Retrotechtacular: The Deadly Shipmate

November 27, 2024 by 33 Comments

During World War II, shipboard life in the United States Navy was a gamble. No matter which theater of operations you found yourself in, the enemy was all around on land, sea, and air, ready to deliver a fatal blow and send your ship to the bottom. Fast forward a couple of decades and Navy life was just as hazardous but in a different way, as this Navy training film on the shipboard hazards of low-voltage electricity makes amply clear.

With the suitably scary title “115 Volts: A Deadly Shipmate,” the 1960 film details the many and various ways sailors could meet an untimely end, most of which seemed to circle back to attempts to make shipboard life a little more tolerable. The film centers not on the risks of a ship’s high-voltage installations, but rather the more familiar AC sockets used for appliances and lighting around most ships. The “familiarity breeds contempt” argument rings a touch hollow; given that most of these sailors appear to be in their 20s and 30s and rural electrification in the US was still only partially complete through the 1970s, chances are good that at least some of these sailors came from farms that still used kerosene lamps. But the point stands that plugging an unauthorized appliance into an outlet on a metal ship in a saltwater environment is a recipe for being the subject of a telegram back home.

The film shows just how dangerous mains voltage can be through a series of vignettes, many of which seem contrived but which were probably all too real to sailors in 1960. Many of the scenarios are service-specific, but a few bear keeping in mind around the house. Of particular note is drilling through a bulkhead and into a conduit; we’ve come perilously close to meeting the same end as the hapless Electrician’s Mate in the film doing much the same thing at home. As for up-cycling a discarded electric fan, all we can say is even brand new, that thing looks remarkably deadly.

The fact that they kept killing the same fellow over and over for each of these demonstrations doesn’t detract much from the central message: follow orders and you’ll probably stay alive. In an environment like that, it’s probably not bad advice.

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Retrotechtacular: A Closer Look At The VT Proximity Fuze

June 9, 2023 by 16 Comments

Here at Hackaday, our aim is to bring you only the freshest of hacks, which carries the burden of being Johnny-on-the-spot with our source material. So if something of obvious interest to our readers goes viral, we might just choose to skip covering it ourselves, figuring you all have probably seen it already. But, if we can dig a little deeper and bring extra value over and above what the viral content provides — well then that’s another story.

That’s pretty much the story behind the excellent video recently released by [Real Engineering] about “The Secret Weapon That Changed World War 2.” It concerns the VT series of proximity fuzes — it’s a legitimate alternate spelling of “fuse” if a somewhat archaic one — that were used for artillery shells and spin-stabilized rockets in World War II. The video gives an excellent overview of the development of the VT, which was used primarily in anti-aircraft artillery (AAA). The details about the development of the American VT fuze are excellent, although curiously there’s no mention that British experiments with a radio proximity fuze were part of the goldmine of information brought to America at great risk by the Tizard mission in 1940. While there has been plenty of contention about the exact role the British work played, it’s fair to say that it at least informed the development and fielding of the American VT fuze.

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Reactivating A Harris RF-130 URT-23 Transmitter

April 8, 2023 by 13 Comments

If you enjoy old military hardware, you probably know that Harris made quite a few heavy-duty pieces of radio gear. [K6YIC] picked up a nice example: the Harris RF-130 URT-23. These were frequently used in the Navy and some other service branches to communicate in a variety of modes on HF. The entire set included an exciter, an amplifier, an antenna tuner, and a power supply and, in its usual configuration, can output up to a kilowatt. The transmitter needs some work, and he’s done three videos on the transmitter already. He’s planning on several more, but there’s already a lot to see if you enjoy this older gear. You can see the first three below and you’ll probably want to watch them all, but if you want to jump right to the tear down, you can start with the second video.

You can find the Navy manual for the unit online, dated back to 1975. It’s hard to imagine how much things have changed in 50 years. These radios use light bulbs and weigh almost 500 pounds. [Daniel] had to get his shop wired for 220 V just to run the beast.

It is amusing that some of this old tube equipment had a counter to tell you how many hours the tubes inside had been operating so you could replace them before they were expected to fail. To keep things cool, there’s a very noisy 11,000 RPM fan. The two ceramic final amplifier tubes weigh over 1.5 pounds each!

The third video shows the initial power up. Like computers, if you remember when equipment was like this, today’s lightweight machines seem like toys. Of course, everything works better these days, so we won’t complain. But there’s something about having a big substantial piece of gear with all the requisite knobs, switches, meters, and everything else.

We can’t wait to see the rest of the restoration and to hear this noble radio on the air again. You can tell that [Daniel] loves this kind of gear and you can pick up a lot of tips and lingo watching the videos.

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Gladys West Modelled The Earth So That We Can Have GPS

August 3, 2021 by 19 Comments

The name Gladys West is probably unfamiliar, but she was part of creating something you probably use often enough: GPS. You wouldn’t think a child who grew up on a sharecropping farm would wind up as an influential mathematician, but perhaps watching her father work very hard for very little and her mother working for a tobacco company made her realize that she wanted more for herself. Early on, she decided that education was the way out. She made it all the way to the Naval Surface Warfare Center.

While she was there she changed the world with — no kidding — mathematics. While she didn’t single-handedly invent satellite navigation, her work was critical to the systems we take for granted today.

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Who Flew Across The Atlantic First? The Airborne Boats Of 1919

July 22, 2021 by 47 Comments

Aviation history is a bit strange. People tend to remember some firsts but not others and — sometimes — not even firsts. For example, everyone knows Amelia Earhart attempted to be the first woman to fly around the globe. She failed, but do you know who succeeded? It was Jerrie Mock. How about the first person to do it? Wiley Post, a name largely forgotten by the public. Charles Lindbergh is another great example. He was the first person to fly across the Atlantic, right? Not exactly. The story of the real first transatlantic flight is one of aviation hacking by the United States Navy.

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Hackaday Links: February 16, 2021

February 16, 2021 by 12 Comments

This is it; after a relatively short transit time of eight months, the Mars 2020 mission carrying the Perseverance rover has almost reached the Red Planet. The passage has been pretty calm, but that’s all about to end on Thursday as the Entry Descent and Landing phase begins. The “Seven Minutes of Terror”, which includes a supersonic parachute deployment, machine-vision-assisted landing site navigation, and a “sky-crane” to touch the rover down gently in Jezero crater, will all transpire autonomously 480 million km away. We’ll only learn about how it goes after the eleven-minute propagation delay between Mars and Earth, but we’ll be glued to the NASA YouTube live stream nonetheless. Coverage starts on February 18, 2021 at 11:15 AM Pacific Standard Time (UTC-8). We’ve created a handy time zone converter and countdown so you don’t miss the show.

As amazing as the engineering on display Thursday will be, it looks like the US Navy has plans to unveil technology that will make NASA as relevant as a buggy-whip company was at the turn of the last century. That is, if you believe the “UFO Patents” are for real. The inventor listed on these patents, Dr. Salvatore Pais, apparently really exists; he’s had peer-reviewed papers published in mainstream journals as recently as 2019. Patents listed to Dr. Pais stretch back to 2004, when he invented a laser augmented turbojet propulsion system, which was assigned to defense contractor Northrup Grumman. The rest of the patents are more recent, all seemingly assigned to the US Navy, and cover things like a “high-frequency gravitational wave generator” and a “craft using an inertial mass-reduction device”. There’s also a patent that seems to cover a compact fusion generator. If any of this is remotely true, and we remain highly skeptical, the good news is that maybe we’ll get things like the Epstein Drive. Of course, that didn’t end well for Solomon Epstein. Or for Manéo Jung-Espinoza.

Of course, if you’re going to capitalize on all these alien patents, you’re going to need some funding. If you missed out on the GME short squeeze megabucks, fret not — there’s still plenty of speculative froth to go around. You might want to try your hand at cryptocurrency mining, but with GPUs becoming near-unobtainium, you’ll have to get creative, like throwing together a crypto mining farm with a bunch of laptops. It looks like the Weibo user who posted the photos has laptops propped up on every available surface of their apartment, and there’s also a short video showing a more industrial setup with rack after rack of laptops. These aren’t exactly throw-aways from some grade school, either — they appear to be brand new laptops that retail for like $1,300 a pop. The ironic part is that the miner says this is better than the sweatshop he used to work in. Pretty sure with all that power being dissipated in his house, it’ll still be a sweatshop come summer.

A lot of people have recently learned the hard lesson that when the service is free, you’re the product, and that what Google giveth, Google can taketh away in a heartbeat, and for no discernable reason. Indie game studio Re-Logic and its lead developer Andrew Spinks found that out last week when a vaguely worded terms-of-service violation notice arrived from Google. The developer of the popular game Terraria was at a loss to understand the TOS violation, which resulted in a loss of access to all the company’s Google services. He spent three weeks going down the hell hole of Google’s automated support system, getting nothing but canned messages that were either irrelevant to his case or technically impossible; kinda hard to check your Gmail account when Google has shut it down. The lesson here is that building a business around services that can be taken away on a whim is perhaps not the best business plan.

And finally, we watched with great interest Big Clive’s secrets to getting those crisp, clean macro shots that he uses to reverse-engineer PCBs. We’ve always wondered how he accomplished that, and figured it involved some fancy ring-lights around the camera lens or a specialized lightbox. Either way, we figured Clive had to plow a bunch of that sweet YouTube cash into the setup, but we were surprised to learn that in true hacker fashion, it’s really just a translucent food container ringed with an LED strip, with a hole cut in the top for his cellphone camera. It may be simple, but you can’t argue with the results.

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The Mark 14 Torpedo — When Just About Everything Goes Wrong, Even The Testing

May 13, 2020 by 70 Comments

I am a fan of the saying that those who don’t know history are doomed to repeat it. After all, humans have been building things for a number of centuries and we should learn from the engineers of the past. While you can learn a lot studying successes, sometimes — maybe even most of the time — we learn more from studying failure. The US Navy’s Mark 14 torpedo certainly has a lot to teach us.

The start of the story was the WWI-era Mark 10 torpedo which was fine for its day, but with faster destroyers and some additional data about how to best sink enemy ships it seemed necessary to build a new torpedo that would be faster, carry more explosive charge, and use a new method of detonation. Work started in 1931 with a $143,000 budget which may sound laughable today, but that was a lot of coin in the 1930s. Adjusted for inflation, that’s about $2.5 million.

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