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Underwater ears everywhere

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Re: Underwater ears everywhere

#131

Post by diracs_stache »

a_bonobo wrote: post #93

There's an interesting link between K-129 and the current 'boom' around deep sea mining: https://en.wikipedia.org/wiki/Project_Azorian The cover-story to build the Glomar Explorer to recover K-129 was that Howard Hughes thought that it was economically feasible to mine manganese nodules from the deep sea. A lot of engineering research started that year (1974) that now, 2023, bears fruit in several large companies try…

The Norman Polmar book on the topic is fairly interesting. Also, I've really turned into my dad reading Cold War non-fiction in bed.

Re: Underwater ears everywhere

#132

Post by romwell »

542458 wrote: post #120
tommiegannert wrote: post #94

Reminded me of this story: https://en.wikipedia.org/wiki/Toshiba%E2%80%93Kongsberg_scan... Toshiba wasn't allowed to export a 9-axis (C)NC-machine to the Soviet union, because it could (and would) be used to create ultra-silent submarine props, in the 80s. Asianometry video about it: https://www.youtube.com/watch?v=uaRyqAVIkwI

It’s kinda wild that the two executives committed fraud to export weapons technology to a major military adversary in contradiction of international agreement… and ended up with 10 and 12 month sentences. That seems really light to me!

The country that issued the sentence is the same country that profited off of the exports and whose government is heavily involved in business deals[1]... so yeah.

Also, the punishment would be not to the executives, but to the company involved (Toshiba) and imposed externally. However:

>In response to the affair, Toshiba carried out lobbying activities in Congress between 1987 and 1989 to ease the sanctions. The amount of money invested by Toshiba, the number of lobbyists, and the scale of its activities were said to be the largest ever.

So, business as usual.

[1] https://en.wikipedia.org/wiki/Government-business_relations_...

Re: Underwater ears everywhere

#133

Post by AlbertCory »

js2 wrote: post #87
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.

I found I'm alarmingly ignorant of the development of radio.

People had household radios in the 20s. Marconi was still alive then. From this admittedly unscientific book, he seems to have been resolutely ignorant of other people's work in the field.

Re: Underwater ears everywhere

#134

Post by rpaddock »

In World-War-One J.H. Rogers demonstrated and patented a method for communication with submarines via special antennas. Anyone have anymore information on these types of systems?:

"James H. ROGERS Underground & Underwater Radio ( Static-free Reception & Transmission Underwater & Underground )" http://rexresearch.com/rogers/1rogers.htm

Re: Underwater ears everywhere

#135

Post by polynomial »

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…

reactor plant noises?

Would like to hear more about this! Assuming the reaction itself is silent (?) what kinds of sounds is the reactor making and what are the challenges in quieting them?

Re: Underwater ears everywhere

#136

Post by kayodelycaon »

wongarsu wrote: post #125
bee_rider wrote: post #113

Earlier quoted context omitted.

Sonar would tell you that there was a boat down there, but not necessarily who was driving it, right?

You can also track the path of the boat, to figure out which port it came from and where it went afterwards. You can also correlate it with AIS, a mandatory tracking signal for ships (used for collision avoidance etc). Of course the ship could have turned it off, but if I owned a bunch of spy satellites I would pay very special attention to any ship that appears on satellite images but doesn't have a corresponding AI…

If the ship is small enough, it wouldn't be required to have an AIS beacon. From an article someone else posted, the suspected ship is a 50-foot recreational sailboat.

Re: Underwater ears everywhere

#137

Post by Eisenstein »

romwell wrote: post #132
542458 wrote: post #120

Earlier quoted context omitted.

It’s kinda wild that the two executives committed fraud to export weapons technology to a major military adversary in contradiction of international agreement… and ended up with 10 and 12 month sentences. That seems really light to me!

The country that issued the sentence is the same country that profited off of the exports and whose government is heavily involved in business deals[1]... so yeah. Also, the punishment would be not to the executives, but to the company involved (Toshiba) and imposed externally. However: >In response to the affair, Toshiba carried out lobbying activities in Congress between 1987 and 1989 to ease the sanctions. The amo…

You know, lobbying wouldn't be so bad if our government officials just ignored them when they were advocating against the public interest.

Re: Underwater ears everywhere

#138

Post by flacebo »

tommiegannert wrote: post #94

Reminded me of this story: https://en.wikipedia.org/wiki/Toshiba%E2%80%93Kongsberg_scan... Toshiba wasn't allowed to export a 9-axis (C)NC-machine to the Soviet union, because it could (and would) be used to create ultra-silent submarine props, in the 80s. Asianometry video about it: https://www.youtube.com/watch?v=uaRyqAVIkwI

When the company I work for was buying a brand new swiss grinding machine (which enables the manufacturing of some extremely precise parts), I had to fill and sign a very strange statement about:

- the exact kind of goods that we will use the machine for

- certify that we will not use it in any nuclear explosive activity, or unsafeguarded nuclear fuel-cycle activity, or the use of nuclear, chemical or biological weapons

- that we won't transfer the manufactured goods or the machine outside of specific countries without the consent of some kind of swiss economic affairs office.

I got the same kind of vibes.

Re: Underwater ears everywhere

#139

Post by Eisenstein »

polynomial wrote: post #135
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…

reactor plant noises? Would like to hear more about this! Assuming the reaction itself is silent (?) what kinds of sounds is the reactor making and what are the challenges in quieting them?

In order to generate electricity from heat, one generally must transform the heat into mechanical energy first. This is most often done creating steam and using it to spin a turbine. I assume that this is the process that is noisy.

Re: Underwater ears everywhere

#140

Post by Eisenstein »

KennyBlanken wrote: post #76
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. Yep; a fanatical obsession with reducing plant noise is why US subs were so quiet compared to everyone else. The author knows fuck-all about what he's talking about going on about cavitation. It's also why diesel hybrid subs from Sweden are nearly undetectable. There's virtually no plant noise - probably just a coolant pump or two - while running on…

Since you are appealing to qualifications, I am genuinely curious what your qualifications are. I have never heard of the author before but I have also never heard of you, so it would be interesting to get your technical background to compare.
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