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Underwater ears everywhere

computer.rip

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Re: Underwater ears everywhere

#81

Post by shoo »

batch12 wrote: post #79

> This website is begrudgingly generated by the use of software. Letters to the editor are welcome via facsimile What does this mean? Is it a reference I'm missing, a vague disclaimer for generated text, or am I reading too much into the footer?

facsimile refers to communication by fax machine, an ancient method of written communication over telephone lines that was popular pre-email, and is still popular in remaining pre-email societies such as federal government departments and japan.

> begrudgingly generated by the use of software

read the top of https://computer.rip/

Re: Underwater ears everywhere

#82

Post by jtwaleson »

batch12 wrote: post #79

> This website is begrudgingly generated by the use of software. Letters to the editor are welcome via facsimile What does this mean? Is it a reference I'm missing, a vague disclaimer for generated text, or am I reading too much into the footer?

I think it just means the author does not like software too much and can be reached via fax.

Re: Underwater ears everywhere

#83

Post by nickelpro »

stuff800 wrote: post #62

> Instead, the battle of submarine silence has mostly revolved around obscure technical problems of fluid dynamics, since one of the loudest noises made by submarines is the cavitation around the screw. Cavitation is loud, but usually only happens if they're running full out. What they're really listening for now are reactor plant noises. > I don't know if this is true today, but at least years ago the low-noise desi…

Huh, I wouldn't classify any of those propulsion trains as pump-jets (and I never heard them called that aboard said vessels ;-P), but wikipedia seems to agree with you.

They're ducted propulsors, a direct evolution of the classic submarine prop that integrates a pressure-increasing shroud and stator vane assembly. A "pump jet" classically involves some sort of centrifugal pump element or at least a vectoring mechanism.

You typically wouldn't call a ducted fan (ex, on the X-22 [1]) a jet, but I guess in the water we do.

[1]: https://en.wikipedia.org/wiki/Bell_X-22

Re: Underwater ears everywhere

#84

Post by zoltar »

vGPU wrote: post #80
supernova87a wrote: post #46

An almost mandatory entertaining article, whenever topics about cables, ocean floor, submarines come up: https://www.wired.com/1996/12/ffglass/ "Mother Earth, Mother Board" (stories about laying undersea cable and the history of wiring the Earth up" (or unpaywalled: https://archive.is/ICkHe )

[flagged]

He didn't take credit for making the wire, so no.

Re: Underwater ears everywhere

#85

Post by AlbertCory »

A question about ELF and VLF for whoever knows:

I just finished reading Thunderstruck (Erik Larson, author of Devil in the White City), which I don't recommend. It ineffectively juxtaposes the story of Marconi with Hawley Crippen, a murderer in London whose case became famous around 1910. (I say "ineffectively" because their stories really don't intersect, IMHO) The book goes on and on about all the demos and tests he ran for years and years, to the point of being eye-glazingly boring. All that aside...

Anyhow: at the very end, the author tells us that Marconi discovered near the end of his life that higher frequencies obviate the need for the gigantic transmitters and receivers he'd been using. Yet he never tells us what frequencies Marconi was using! Does anyone know?

Re: Underwater ears everywhere

#86

Post by namibj »

nickelpro wrote: post #83
stuff800 wrote: post #62

> Instead, the battle of submarine silence has mostly revolved around obscure technical problems of fluid dynamics, since one of the loudest noises made by submarines is the cavitation around the screw. Cavitation is loud, but usually only happens if they're running full out. What they're really listening for now are reactor plant noises. > I don't know if this is true today, but at least years ago the low-noise desi…

Huh, I wouldn't classify any of those propulsion trains as pump-jets (and I never heard them called that aboard said vessels ;-P), but wikipedia seems to agree with you. They're ducted propulsors, a direct evolution of the classic submarine prop that integrates a pressure-increasing shroud and stator vane assembly. A "pump jet" classically involves some sort of centrifugal pump element or at least a vectoring mechani…

I counter (ultra) high bypass turbofan.

Re: Underwater ears everywhere

#87

Post by js2 »

AlbertCory wrote: post #85

A question about ELF and VLF for whoever knows: I just finished reading Thunderstruck (Erik Larson, author of Devil in the White City ), which I don't recommend. It ineffectively juxtaposes the story of Marconi with Hawley Crippen, a murderer in London whose case became famous around 1910. (I say "ineffectively" because their stories really don't intersect, IMHO) The book goes on and on about all the demos and tests…

I loved Devil in the White City so it's too bad to hear that you didn't find Thunderstruck very good.

Marconi was working on developing microwave transmission at the time of his death. Microwave antenna are small but are only good for line of sight transmission.

Re: Underwater ears everywhere

#88

Post by dumpsterdiver »

vGPU wrote: post #80
supernova87a wrote: post #46

An almost mandatory entertaining article, whenever topics about cables, ocean floor, submarines come up: https://www.wired.com/1996/12/ffglass/ "Mother Earth, Mother Board" (stories about laying undersea cable and the history of wiring the Earth up" (or unpaywalled: https://archive.is/ICkHe )

[flagged]

Jesus man, will you ever get over Trump or is this going to be your entire discourse from now on?

Edit: Btw, I upvoted you, because I want your words to be seen.

If you have nothing else to contribute aside from, "fuck this politician who is long out of power", then you aren't really contributing.

Re: Underwater ears everywhere

#89

Post by Doxin »

stuff800 wrote: post #62

> Instead, the battle of submarine silence has mostly revolved around obscure technical problems of fluid dynamics, since one of the loudest noises made by submarines is the cavitation around the screw. Cavitation is loud, but usually only happens if they're running full out. What they're really listening for now are reactor plant noises. > I don't know if this is true today, but at least years ago the low-noise desi…

> What they're really listening for now are reactor plant noises.

Which is why old timey diesel electric submarines still sometimes have the edge over modern subs. No plant noises at all if they are running silent.

This leads to some hilarity in joint naval exercises every now and then. e.g. when HNLMS Walrus managed to "sink" among others the USS Theodore Roosevelt before getting away, to great consternation of the Americans.

Re: Underwater ears everywhere

#90

Post by defrost »

Doxin wrote: post #89
stuff800 wrote: post #62

> Instead, the battle of submarine silence has mostly revolved around obscure technical problems of fluid dynamics, since one of the loudest noises made by submarines is the cavitation around the screw. Cavitation is loud, but usually only happens if they're running full out. What they're really listening for now are reactor plant noises. > I don't know if this is true today, but at least years ago the low-noise desi…

> What they're really listening for now are reactor plant noises. Which is why old timey diesel electric submarines still sometimes have the edge over modern subs. No plant noises at all if they are running silent. This leads to some hilarity in joint naval exercises every now and then. e.g. when HNLMS Walrus managed to "sink" among others the USS Theodore Roosevelt before getting away, to great consternation of the…

C'mon though, which US joint exercise partner hasn't 'sunk' a USS craft at one time or another yet?

Not to mention the actual real sinkings that are a standard feature of pretty much every RIMPAC nav-mil-cosplay LARP event:

* https://gcaptain.com/australian-sub-sinks-us-navy-ship-pract...

* https://www.businessinsider.com/us-australia-japan-practice-...

* https://news.usni.org/2020/08/31/video-rimpac-2020-exercise-...

The thing about ships from the Netherlands though, they pretty much sink themselves locally:

https://en.wikipedia.org/wiki/Shipwrecks_of_Western_Australi...

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