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Sonic Torpedo Defense
dylanduck writes "How do you defend a ship against torpedoes? According to the US Navy, you line the hull with loudspeakers and blast the incoming missile with such a devastating blast of sounds that it explodes." When asked about the possible ecological effects on marine life the military had no comment.
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When asked about the possible ecological effects on marine life the military had no comment.
We care... why? My guess is that a large sonic blast is going to be a lot less harmful than a torpedo detonating. But that's just me.
We need to be cautious, as Britney Spears at 200db could have a devistating effect on the entire oceanic ecosystem.
Everyone on the ship will have all you can eat seafood for weeks.
Bonus if you get some giant squid.
2 years and no mod points. Join reddit. Because openness is good.
To get best results they need gold power cables at 1000 for each speaker :)
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Reading TFA, the concern is not over the effects of sonic blast vs. sinking ship.
The concern is the effect of open-water testing of the sonic blast against simulated or dummy threats in the ocean.
Actually, being an acoustician, I would be willing to bet that they would use a phased array of loudspeakers. With the correct phasing of the speakers, some pre-determined "point" in the water could be driven to very high sound pressure levels, while the remaining ambient noise, while still loud, may not be all that dangerous. This would occur as a transient excitation from the various loudspeakers propagates away from the source and coalesces at the point in the water where the torpedo is located, the point where a very large pressure spike is generated. There are plenty of smart researchers in the navy and I have my doubts that they would use anything other than a phased array. And by the way, this is the same methodology that they use to destroy kidney stones.
Name: Mr. Anon E Mouse; SSN: 555-55-5555
> This is like shooting down missles with lasers; just make a shiny
> missile and the light bounces off without damaging it.
Utterly ineffective. At intensities high enough to be useful the electric field of the laser pulse rips electrons out of the surface of the target. This creates a plasma which absorbs more energy from the pulse, explodes, and blows a piece out of the surface. It makes no difference at all what material the target is made of or how it is polished. This effect has been experimentally verified.
It's also how LASIX works.
> You can probably render the sound blast torpedo killer worthless
> just by skinning the torpedos in cheap appropriately sound
> absorbing material. Perhaps a derivative of foam or rubber.
Failed freshman physics, did you?
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
I bet those of you making the "but what about the animals" comments would care less about the animals if you had friends or relatives serving on a ship that could be a torpedo target.
I love animals, I'm all for ecology and protecting wildlife, etc etc. I own a big chunk of land, and I don't cut a bush or move a bolder without thinking about what it might do to the animals...and 99 percent of the time, I let the animals win. But when the choices are limited to 'humans live but animals die' and 'humans die but animals live', I'll take choice number one every time, and with no regrets what so ever.
I want a new quote. One that won't spill. One that don't cost too much. Or come in a pill.
I am a former sailor in the US Navy, my particular job was working with the Aegis weapon systems. Just because the system is installed on board doesn't imply that it gets used during a simulation or exercise. We have missiles and guns but very rarely ever fire a live round during training. We have electronic counter measures but those do not get set off either. Why waste the equipment and materials if they can be simulated via computer instead? But then how do you know the stuff works? Every bit of equipment has a planned maintenance schedule that is closely followed. This includes tests based daily, weekly, monthly, yearly etc. They are also very aware of the potential dangers, more so than you that is clear. The Navy is very careful about operating withing specific guidelines when it comes to the environment, they observe all of the whale habitats along the US costal waters and any other environmentaly sensative areas.
I've asked him about how powerful the sonar was and to give you an idea how dangerous it is he told me about some standard submarine procedure. Basically, if a submarine comes under threat from enemy frogmen or divers, the defence the sub has is to turn the active sonar on and start pinging. If a diver is underwater and within a couple hundred yards, he will die from the intensity of the sound under water. In other words the sonar is VERY powerful. Trust me a 200db blast will likely give someone a very bad day if they are near by.
and currently stationed by iraq. While I say the more defensive weapons the better, if we have to do it at the expense of making all the whales extinct I say its not worth it. This isnt about saving plankton here, this is about not accidently blowing away the eardrums and thus killing thousands of whales and other marine creatures. There have been experiments with this technology and coincidentally there were massive beachings as the marine mammals could no longer navigate correctly. There are billions of us, I can't say the same for the whales.
http://www.livejournal.com/users/cixel
Just about anyone with a relatively big boat has to repaint the hull with antifoul paint every couple years. Not really that nasty, now, it's simply marine paint mixed with a bunch of (correct me if i'm wrong) aluminium dust. The older stuff used primarily copper, which had a few adverse effects on sea life.
Apparently some of the Cajuns down south use cayenne pepper, and they claim it works the best, but hey, to a cajun, cayenne pepper's good for damn near anything.
The navy these days has actually been using some pretty wierd coatings for ships, although mainly subs, in order to reduce friction.
My other Sig is
Oh, right. Because we would *hate* to have a loud noise in the ocean instead of thousands of gallons of fuel oil or a ruptured nuclear reactor from a sunk ship.
Brought to you by the same retards who nixed nuclear power for environmental reasons, forcing the country to depend on burning coal.
If you are maneuvering at flank speed with active sonar, trying to dodge an incoming torpedo, it's safe to say that stealth is not one of your hallmarks.
Mea navis aericumbens anguillis abundat
I was about to post that there were only two nuclear powered non-carrier surface ships in the Navy (the two my father helped build), but my favorite source indicates there were nine nuclear-powered guided missile cruisers (CGN's), the last of which were decommissioned in 1998.
IIRC, the US built one proof-of-concept nuclear-powered merchant ship (the Savannah) in the 60's, and the Soviet Union built at least one nuclear-powered ice-breaker.
Slashdot: a convenient dumping ground for the trivia that clutters our minds...
P.S. I have to add that pausing to contemplate environmentally safe warfare is laughable; this is a classic case of wanting to treat the symptom instead of the disease.
I'm 90% sure I know what this is for. I'm not a naval warfare specialist, but I am a scientist with an interest in these things.
In the 1990s, the Russians developed the prototype for what would later be termed the Shkval or Squall supercavitation torpedo. Knowing the Russians, the Chinese probably have them too.
Cavitation is a phenomena where a body moving through the water pushes the water out of the way so fast that it creates bubbles around the object (fast = lower pressure = water vaporization = bubbles). You may have heard of propellers cavitating - that's where small bubbles of water vapor form then burst on the low pressure side of a prop blade, causing lots of noise and even damage to the blade when they implode.
Supercavitation, on the other hand, is an intentional phenomena where a blunt-nosed object is shot through the water, creating low pressure vortices on the sides. Air or exhaust gases are injected into these vortices, creating a static "bubble" around the object that drastically reduces friction - perhaps up to an order of magnitude. You have to fire these things at about 50mph or greater to start the supercav effect going, effectively "handing off" the bubble to the torpedo, which then sustains it.
The numbers on these torpedoes are incredible: we're talking about a 300mph torp carrying a 460lb warhead with a range in excess of 7000 yards. That's the tame version - others carry nukes. In other words, carrier-killers.
Supercavitation torpedoes, as you can imagine, are incredibly noisy and easy to detect - you just can't get away from them because they're so fast. This sonic projector essentially sends a high-energy single pulse through the water directed at an incoming torpedo. That pulse probably wouldn't be able to crack a torpedo - you'd probably need on the order of 250-500PSIG overpressure to do that, (scuba tanks contain 2000PSIG regularly). You wouldn't be able to detonate the high explosive, because you need a wavefront speed above the detonation velocity, which for C4 is about 7000m/s (much slower than the speed of sound in water, 1482m/s).
I don't have the time right now to spin the equations, so I could be wrong.
However, you would be able to disrupt and dissipate that bubble around an incoming supercavitation weapon with a high-energy sonic pulse. Break that bubble, and the torp stops dead in the water because it can't reform the bubble around itself. If it mistakes that sudden stop for a ship hull - boom.
'Be always mindful, even when ditch-digging.' --D. T. Suzuki