2008-03-06 12:42 AM
2008-03-06 05:29 AM
2008-03-06 05:47 AM
2008-03-06 05:53 AM
2008-03-06 06:11 AM
2008-03-06 10:09 AM
Peter wrote:In addition to your submarine propeller question to Dwight I also would like to ask Dwight if you also know how to analyze submarine propeller sound? We had an infamous submarine visit here close to Stockholm in the eighties, and we sill don't know if it was a US or Russian sub. The marine have some recorded sound but they are not clever enough to figure out who came to see us.
Thank you Dwight,
Now both Raul and I have the the section fairing lines
to make this kind of blade.
As usual, you have taught me something. This time about propeller blades.
Now I wonder if you know something about submarine propellers.
They are different from normal surface boat and ship propellers
Thanks,
Peter Devlin
2008-03-06 07:29 PM
2008-03-06 08:07 PM
2008-03-07 09:06 AM
Dwight wrote:Haha! You're the man!
Depends who is listening.
The Americans make out the Russians to be bad guys, so of course they want to be superior - making less sound, but the movieHunt For Red October, a tome of science and accuracy, indicates that sonar is inexact.
The American submarine, buoyed as it is by the hubris of inherant technological superiority probably is quieter. There's probably an undertone of "nyah nyah" in the American sound. "Throb… nyah… throb… nyah…raspberry sound… ruskies go home!!!"
The Americans teach their sonartechs to listen for steam jets, cracking donkey thigh bone piston rods and the clank of rolling vodka bottles.
Of course i am joking. The Americans have a greater tax base, a larger population and less domestic problems at home. They have more money to make a quiet submarine including rubber propellors. You don't see any web site where appealing American women doctors are signing up to be brides in Russia, do you?
There was one thing that told me volumes about the technical differences between these countries. At Expo 86, a "transportation" theme fair we held here in Vancouver, the Soviets [at that time] sent a spacecraft for exhibit. Looking at the command station, there was a fine, hand-tooled cowhide document pouch holding a large TIN [!] of Estonian bacon, a big hunk of dense black bread [floating zero-gravity CRUMBS], and a GLASS bottle of vodka. Their Soyuz [?] boosters deliver a higher payload than the American Apollos - and their use to launch tins and bottle while the Americans made powdered tang and the tiny calculator tells me that they can use brute force to get things done whereas a quiet submarine propulsion system is a matter of finesse.
2008-03-07 09:43 AM
2008-03-09 05:55 PM
Dwight wrote:Reminds me of a story ...
Depends who is listening.
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they can use brute force to get things done whereas a quiet submarine propulsion system is a matter of finesse.