Acoustic Analysis of Submarines

[Pericles]

You had better equipment in '52 than the RN through WW2. Here is a site that is dedicated to one of the best sub killers. His son died in a British sub in the Med and Capt. Walker died as a result of of overwork. I think you will find the site of interest.

http://www.mikekemble.com/ww2/walker.html

I have a cherished copy of Yankee RN - Commander AH Cherry who was a Wall Street Banker who joined the RN before America entered the war.
http://www.marywardbooks.com/books/Y...Z02.htmregards,

Cherry became Number 1 (First Officer) on HMS Wren in Walker's flotilla

Regards,

Perry

[tspeer]

Originally Posted by Pericles

...Knowing that some of the maddest ideas might work somehow. perhaps the equipment exists...

ASW is actually a huge exercise in applied spectral analysis. MAD is only for pinning down the precise location of the sub once it's been located by sonar. And it's passive sonar that is used for detecting the sub and getting it's general location. I've had the chance to operate the systems onboard an S-3 Viking running a training tape. We hunted phantom subs in California's Rogers Dry Lake. Fun!

[FAST FRED]

ASW is actually a huge exercise in applied spectral analysis. MAD is only for pinning down the precise location of the sub once it's been located by sonar.

The use of passive sonobuoys will find a sub in a wide area , the hassle is "localizing" ,,getting close enough that a torpedo will find it.

This uses a large circle of sonobuoys with PDC (practice depth charges) dropped as the aircraft goes over the top of each buoy (that transmits on its own seperate frequency. The PDC noise will bounce off the bottom AND off the sub hull.

The time delays allow a circle to be drawn around each buoy , where they cross , is the last location of the sub. 3 buoys allow any ambiguity to be resolved. But PDC are active searching , the noise in the sub is huge !!

The MAD gear is only used in the attack phase (short range), where the course and speed are checked and the fish laid in the water in front of the target.

Of course this only works well for diesel subs , as the speed of a nuke will get it out of the entrapment circle at the cost of lots of noise.

At least thats how it was in the 1960's , looking down from a P2V7.

Today I expect the torpedos are lots quicker and can catch a 60K target.

FF

[Guillermo]

Searching Leo's suggested link, I've found this three interesting technical reports:
http://www.dsto.defence.gov.au/publi...hp?record=3919
http://www.dsto.defence.gov.au/publi...hp?record=8027
http://www.dsto.defence.gov.au/publi...hp?record=3824

Highjacking this thread for a while:
Last monday (2008/03/10) I was invited to the launching of the strategic projection vessel "Juan Carlos I" in Ferrol, Galicia.
http://www.navantia.es/irj/go/km/doc...afee00dcbb.xml
http://en.wikipedia.org/wiki/Buque_d...trat%C3%A9gica
The spanish Navantia has sold two of those to the Australian Navy, to become the new Camberra-class of large amphibious ships, as well as the design & engineering for the building of the new breed of Australian frigates.

Cheers.

[brian eiland]

Originally Posted by Pericles

Should we even be discussing this? Walls have ears. Perry

I agree with you Perry, I do not think we should be discussing this here. This sounds very much like a fishing expedition by a Chinese person.

Sorry, but I spent some time with the subs, and I'm old enough to remember the cold war, and I am concerned about our future relationship with China.

(this concern is not just about an aggressive China, but rather her emergence as the second BIG-est energy competitor, and the failure of establishing a realistic negotiation relationship with them)

There was an old saying during WWII;

Loose Lips Sink Ships

http://www.phrases.org.uk/meanings/237250.html
http://www.nh.gov/ww2/loose.html

[yipster]

sure great technology and more but even if walls did not have ears i say with Admiral Hyman George Rickover "sink them all"

Given Rickover's single-minded focus on naval nuclear propulsion, design and operations, it came as a surprise to many when in 1982, near the end of his career, he testified before the U.S. Congress that, were it up to him, he "would sink them all." A seemingly outrageous enigma of a statement – and perhaps one attributable to an old man beyond his time – in context, Rickover's personal integrity and honesty were such that he was lamenting the need for such war machines in the modern world, and specifically acknowledged as well that the employment of nuclear energy ran counter to the course of nature over time.

interesting in this is that via this site i came to a natural fission site. some million years ago uranium was not so depleted as today and there are places found that had natural nuclear fission for thousends of years.

from seawater today's submarine fission plants produce oxigen in abundance and pump hydrogen simply overboard, possible there is a second live for those subs..