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#51
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On Sun, 30 Jan 2005 20:34:03 -0600, Jim Carriere
wrote: Michael Wise wrote: In article , wrote: Since I am relying on what was taught from basic physics, I will presume that while training might change, objective reality does not. As I have said, I agree on most of what you've said...with the exception that a diesel sub is easier to detect passively when snorkeling than when running on the surface. I don't see any laws of physics supporting that argument. I've heard the same thing (the snorkeling sub is "noisier" in the water than the surfaced one). More hull is in the water, so more noise is transferred to the water and less is transferred to the air. Bingo!!!!!!!!!!! I'm not convinced that there is a great deal of difference, it seems overly simplified to me. I have a feeling that water is better than air at absorbing sound, by which I mean that a surfaced sub probably transfers nearly all of it's engine noise to the water anyway. No, Sir, you have backwards. :-) Water is a most excellent transmitter of sound, while air is the Great Absorber. The speed of sound in water at 15C is 4814 ft/sec. In air at 15C is 752 ft/sec. This is the major reason why all that sound radiated by a submerged hull is so detectable. This is also why the SOSUS network, one of the really Big Secrets of the ASW world, works so well. For a practical application, pick up a piece of accoustic tile. I'll bet you see a lot of air and no water!!!!! ;-) I can understand why someone steeped in active sonar tactics might be skeptical of passive capability. But that skepticism should be a challenge to reconsider. The physics is pretty basic and has not changed, no matter what the personal experience. Bill Kambic |
#52
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"Guy Alcala" skrev i meddelandet . .. For the AIP subs coming into service now, it's a looong time. See http://www.chinfo.navy.mil/navpalib/...propulsion.htm Coming into service now?? The RSwN have been operating AIP subs since 1989. http://www.kockums.se/Submarines/nacken.html Regards, Per Nordenberg |
#53
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Pechs1 wrote:
When the balloon goes up with China, hopefully we will destroy the diesels in port before they end up in the straights. If anybody thinks China is our best buddy, needs to get a clue. P. C. Chisholm CDR, USN(ret.) Old Phart Phormer Phantom, Turkey, Viper, Scooter and Combat Buckeye Phlyer Well until the sweet & sour chicken embargo starts, I will consider them competitors. Not quite "buddies." :-\ China wants to be a bigger player in the Pacific, but I doubt they are ready to get nasty. Besides, we need them to keep a rein on North Korea & to keep making Winchester '97 clones. |
#54
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#55
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On Mon, 31 Jan 2005 19:19:56 GMT, Tiger
wrote: Besides, we need them to keep a rein on North Korea & to keep making Winchester '97 clones. And, soon Winchester 1887 clones!!!!! :-) Bill Kambic |
#56
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On Mon, 31 Jan 2005 20:39:20 GMT, Michael Wise wrote:
No, I was the S-2 tactics instructor. I saw through most of the AW portion to find would what was taught and learn more about the capabilities of the equipment. Does that mean you have not actually operated ASW avionic to detect, localize, and track a sub, but are speaking based on classes you sat in on? You have asked two questions. So you get two answers! :-) I have never flown an operational or training mission in the No. 4 seat. Nor, in the P-3, did I ever sit in either of the acoustic seats and analyze grams. I am not, however, speaking solely from classroom knowledge (although in this case classroom knowledge would be sufficient). The S-2 and (IIRC, the P-3) permitted the aircraft commander to listen to any bouy that was up. We would routinely discuss contacts and their characteristics. And educated CAPC (carrier air place commander) was considered a Good Thing. On multiple occasions we tracked U.S., Allied, and Soviet/Block subs both active and passive (although going active on a Soviet/Block sub required specific clearance from the Flag). I would NEVER claim that I tracked or localized anything. My crew and I did. Bill Kambic |
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#58
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Michael Wise wrote:
In article , Jim Carriere wrote: Since I am relying on what was taught from basic physics, I will presume that while training might change, objective reality does not. As I have said, I agree on most of what you've said...with the exception that a diesel sub is easier to detect passively when snorkeling than when running on the surface. I don't see any laws of physics supporting that argument. I've heard the same thing (the snorkeling sub is "noisier" in the water than the surfaced one). More hull is in the water, so more noise is transferred to the water and less is transferred to the air. I'm not convinced that there is a great deal of difference, it seems overly simplified to me. I have a feeling that water is better than air at absorbing sound, by which I mean that a surfaced sub probably transfers nearly all of it's engine noise to the water anyway. Indeed. Snorkeling or surfaced, it's noise begs for a couple MK-46's. --Mike Or eight Mk 54's at fifty foot spacing... -- -Gord. (use gordon in email) |
#59
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Jim Carriere wrote:
I've said it before, I believe a .50 caliber machine gun on a helo is a better ASW weapon than any air dropped torpedo. Most of the time you find a sub it will be on or near the surface taking a look. The gun will make his life difficult because you will definitely hit him with enough of the bullets. A perfect torpedo shot is pretty rare, and even then it still might miss. Would a fifty be of much concern to a sub?...I know that we had a pair of .303's on Lancasters and they told us that it's value was in keeping the sub's crew from manning their deck gun...do subs even have a deck gun now? I doubt it. -- -Gord. (use gordon in email) |
#60
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