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Low Frequency Active Sonar Gains US Gov. Approval

Posted by michael on from the can-you-hear-me-now dept.

burntout writes "According to bbc online the US government has finally approved the use of low frequency active sonar. Apparently the navy has been granted an exemption from the marine mammal protection act for this, which is apparently 'necessary because of new superquiet Chinese, Russian, and German subs'."

14 of 68 comments (clear)

  1. Germans? by nosferatu-man · · Score: 3, Funny

    We taught them a lesson, in 1918,
    and they've hardly bothered us since then. - tl

    --
    To spur "enterprise Linux," Big Bang, the distributed two-phase commit.
  2. This is an overhyped issue... by duffbeer703 · · Score: 3, Informative

    Active sonar is only used in emergency situations.

    Using an active sonar array advertises your position to any other submarines in 30-90 nm radius.

    The most common use for active sonar is to acquire a definitive lock on a target after torpedoes have been launched.

    --
    Conformity is the jailer of freedom and enemy of growth. -JFK
    1. Re:This is an overhyped issue... by heikkile · · Score: 5, Funny
      Using an active sonar array advertises your position
      to any other submarines in 30-90 nm radius

      Who cares! Once they are within a micrometer, or even a whole
      meter from you, you are toast anyway!

      --

      In Murphy We Turst

    2. Re:This is an overhyped issue... by Yunzil · · Score: 3, Insightful

      Active sonar is only used in emergency situations

      Not entirely true. :)

      Sometimes it doesn't matter if you advertise your position. Active detective ranges are so much longer than passive detection ranges that sometimes it's possible to just ping like hell and hold the threat at standoff range until you are ready to kill them.

    3. Re:This is an overhyped issue... by gonar · · Score: 3, Informative

      actually, on normal targets passive detecion range is much greater, but less precise. you know where he is, but not quite precisely where.

      however, today's submarines are sooooo quiet, that they make less noise then the ocean background.

      active is great for very high precision location at relatively short ranges.

      if you are banging out active pings, your nice quiet enemy, just outside your active detection range knows where you are and can fairly easily maneuver around you.

      the counter tactic to this is a team of subs, some pinging and some passive, with the passive guys in the gaps trying to catch the sneaky bastards....

      --
      The difference between Theory and Practice is greater in Practice than in Theory.
  3. Visual scan for marine mammals... by alwayslurking · · Score: 3, Funny

    ...how very sophisticated. Guess the Navy can add whale-watching trips to their recruitment literature now.

  4. re: overhyped issue by burntout · · Score: 4, Informative

    . . . good point DuffBeer; however, if you had read the article, you might have noticed that this is towed array sonar, based on ships. The issue here is not stealth, it is detection.

  5. Sonar and whale strandings by Peter+T+Ermit · · Score: 5, Interesting

    Though this issue is a bit overhyped, once in a while, the Navy does kill a few whales. For instance, in March, 2000, 17 beaked whales died due to getting battered with sonar. (Link to NOAA press release here.)

    1. Re:Sonar and whale strandings by JabberWokky · · Score: 5, Funny
      And the Army probably mauls a few dozen rabbits, groundhogs and skunks under tanks and troop carriers. The Air Force nukes its share of birds with high powered radar.

      And a van full of PETA demonstrators recently hit a deer while driving to some protest.

      --
      Evan

      --
      "$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
  6. 235 decibels or greater ! by UranusReallyHertz · · Score: 3, Interesting

    Holy sheeet! Anyone know how much juice that must take? http://www.fas.org/irp/program/collect/lfa.htm The shallow-water acoustics problem has risen in importance due to the increased salience of regional conflicts where the US Navy may to encounter slow, diesel submarines close to shore. The shallow-water, slow submarine is significantly more difficult to detect and classify acoustically than the cold war threat, due to the complex propagation, high clutter, and low target Doppler. Effective sonar performance requires new processing algorithms which cannot be implemented on current Naval platforms due the high processing requirements. A Hybrid Digital/Optical Processor (HyDOP) is to demonstrate the feasibility of using embedded scalable high performance digital and optical processing to solve this problem. This requires application of computationally intensive algorithms which cannot be implemented in real time using conventional processors. A high-speed optical correlator being developed by the Naval Research Laboratory (NRL) will act as a coprocessor to an Intel Paragon XP/S-25 computer.

    --
    Smoking is an expensive, slow, and unreliable method of suicide.
  7. War is good... by noxavior · · Score: 5, Insightful

    To provide excuses for any action. Destroying the world's most peaceful creatures because we want to kill each other is ironic and disgusting.

    --
    Karma:This parrot is dead! (and so is the joke.)
    1. Re:War is good... by Daniel+Dvorkin · · Score: 3, Interesting

      We aren't the only animals with hands, nor with big brains, but we're the only ones who have both hands and the brains to use our hands to develop much in the way of technology. (As one of the Leakeys pointed out, many other animals make tools; the critical distinction between us and them is that we _use tools to make tools_. After that, there are no limits.) But we're not the only violent animals, nor in fact are the only ones who fight wars -- read up on baboons some time.

      Look, I'm not defending killing whales, nor bombing wedding parties. But the idea that the rest of nature is gentle and peaceful and we're the only ones who destroy each other and/or our environment is romantic foolishness.

      --
      The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
  8. Extremely sad by MrIcee · · Score: 5, Interesting
    This is on our front pages of todays paper here in Hawaii. This is a blow for the island and the marine creatures that surround it.

    Yes... it causes whales and dolphins to die. Much of the experiments were carried out in the water around Hawaii, thanks to the military idiots that abound here.

    And yes, they know that it cause havoc with the animals. It's sad, because whales travel thousands of miles each year to give birth to their babies off the coasts of our islands. Not only will this dissrupt their normal cycle of life, but also will drive them away (which also hurts our tourist industry as well as our scientific industries who try to study the whales).

    But, like everything else... our government has it's preverbal head up it's ass and only thinks of itself with it's MIGHT MAKES RIGHT mentality.

    I think personally, it is time for Hawaii to secceed the US... kick out the military, and bring back a balance to life on these beautiful islands.

    1. Re:Extremely sad by p3d0 · · Score: 3, Insightful

      Can you imagine a sound so loud that it kills you? It's mindboggling. Not a nice way to die. I have heard estimates as high as 235 decibels. That's a hundred thousand times louder than pressing your ear up against a jumbo jet engine.

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....