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Acoustic Switches, Oil Spills and Wikipedia Experts

By: Steve Maley (Diary)  |  May 25th, 2010 at 07:01 PM  | 

RESIZE: AAA

The Daily Beast’s Rick Outzen is like a dog with a bone. Rick (along with a legion of other self-imagined experts on the ‘net) is getting a lot of mileage out of the notion that an acoustic switch (see diagram below the fold) might have averted disaster on the Deepwater Horizon:

We know that the Deepwater well lacked the remote-control, acoustical valve [sic] that experts believe would have shut off the well when the blowout protector [sic] failed. The acoustic trigger costs about $500,000.  [emphasis added]

“Experts believe”? Link, please?

The blind/shear rams, the ‘business end’ of the BOP failed, presumably jammed; how would an alternate switching device have closed them? We have all seen the video of the ROV attempting to operate the rams manually (well, sort of) to no effect. Does your “acoustical valve” work by magic?

As far as I can tell, the acoustic switch has only been tested in simulation, never in a real emergency. All deepwater contractors are required to use redundant shut-in systems on their rigs, a system that has proven itself reliable for years, up until the Deepwater Horizon. blowout. The reason that one failed has yet to be determined.

The environmental lawyer in the linked video refers to the acoustic switch as a “fail-safe”. Ain’t no such thing, sport, and that’s the kind of thinking that gets people in trouble.

Cross-posted at VladEnBlog.

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COMMENTS

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  • mark1957

    just use his sonar powers to trigger the switch, another method would be to use a giant clam to pinch the pipe shut.

  • Next93

    One of my most reliable idiot-detectors is watching for the use of the term ‘failsafe’; it’s almost always used incorrectly by non-engineers holding forth on politically significant engineering issues.

    For the record, a failsafe system is one that literally fails in a safe condition – power and/or control must be functioning in order to enter and remain in an unsafe state.

    Classic examples are the Otis elevator brake (tension on the cable opens the brake, if the cable snaps the brakes retract and stop the elevator) and the Westinghouse pneumatic railroad brake (pressure in the lines is necessary for the car to move).

    However, just because a system has a failsafe design does NOT mean that it can’t suffer a catastrophic failure of a critical part (that’s known as a single- node failure).

    • JoeG

      Fail safe just means that the most likely failure is in a safe state. It in no way means all failures result in switching to a safe state.

      • Next93

        You’re not the idiot in that conversation. What they’re describing is a fault-resistant design, but to call it “failsafe” is flat-out wrong.

        Personally, I think that sort of design thinking is delusional. The very fact that the system is in a failure mode means that it’s operating outside design parameters – something that the designer’s deemed as “unlikely” (iif not outright impossible) has already happened, and at that point, all bets are off. You’re operating in a regime in which your carefully thought-out scenarios of “likely events” means exactly jack.

        I should have pointed out that there are a lot of applications where failsafe simply isn’t possible – any system in which active control is needed to return from an inherently unsafe state. The flight control system on the space shuttle is a prime example – during launch and re-entry a loss of control means a loss of vehicle, and there’s no way around that. You deal with that sort of thing by designing in redundancy (the shuttle has 5 flight computers and two different software versions). Even then, there’s going to be scenarios where the system simply can’t survive (like Apollo 13).

        Bottom line is, there’s always going to be risk in anything but the most simple design. Once you’ve done your best to design a safe system, you need to have a plan in place to minimize impact if the worst happens, and that’s the part that the government (not BP) failed at.

  • ss396

    An acoustic switch would need to transmit a signal clearly enough, directionally enough, and powerfully enough to (a) not be confused by the sensor with background sea noise, refraction noise off the seabed, impulse noises from the drilling activity, etc., and (b) still not harm the whales. We could have done it if it hadn’t been for them danged whales! I blame them.

    • roscopico

      Yeah, yeah, Giant polar bears. And the smoke monster. Whatever it was, it’s bound to be back soon just to make Obama look bad because it’s racist.

      That’s why we need to stop all drilling, mining, space exploration, commuting, swimming, and everything else.

      I saw a car accident once, and for the life of me I can’t figure out why they still let us drive.

  • loupgarou1317

    Boys and Girls, it just goes to show why the IDIOTS that design the things do NOT work on them!! I have been a mechanic for over 15 years in both general (cars and light trucks) and specialized (airport Ground Equipment/Fuel Delivery) and there is no such thing as a “fail safe”…….You try to make it as hard as possible for them to break it and THEY STILL DO ANYWAY!!! Well though, this just shows that if you do not know what you are talking about………….JUST SHUT THE FRAK UP!!(Sorry, It just gets on my nerves when those that think they know try to act like they know everything.)

    • JoeG

      The people who are “experts” here are not designers nor maintenance workers.

      They are simply armchair experts.

      • Adjoran

        That implies people who are well-read on the subject, although lacking direct experience in the field.

        This isn’t the case here. These “experts” are people who read something on the interwebs and believed it, and people who are either advocates of a political position or trying to sell something.

        In fact, this is the most common way “knowledge” is spread on the Left.

  • Richard Mullins

    and this all sort itself out. The whole thing is complex and the interference from these wanna-be experts and our federal government is getting in the way. I have a link on the Houston Chronicle on what BP is looking at on the cause. It’s very complex.
    BP tells what it’s looking at as cause of Spill

    These morons shouldn’t even be talking about something that they no nothing about.

  • kdoc

    Call Jack Bauer. Now that he’s no longer fighting terrorists, he can singlehandedly dive down to the wellhead and shut it off. That’s if he has to do it while holding his breath. If you give him some oxygen, he could reconnect the pipe and bring it back to the surface to allow the oil to flow freely into tanker ships.

    At least my solution is as plausible as anything the guvmint can come up with.

    • Raven

      Either you think Jack Bauer is better than he is or you’re getting them mixed up…

      • http://itsaboutfreedom.proboards.com Conservative Phantom

        Jack Bauer is a fictional character who does the impossible while Chuck Norris is a real person who merely thinks he can do the impossible.

        Everyone knows, though, that only Ted Nugent can actually pull off the impossible.

        • Raven

          He wouldn’t have to pull it off.
          And we’d all breathe a sigh of relief, too.

  • Deskpilot

    With each passing day, the hydrological condition of the water in the Gulf are changing. As a US Navy trained submarine hunter, I can tell you that sound does not travel in the vertical column of water very well (no pun intended). An acoustic pulse transmitted vertically, in an attempt to reach over 5k ft of water would have to have a tremendous amount of power behind it in order for even the faintest signal to reach that deep.
    Additionally, the variation of temperature changes as the signal descends, the water.oil mix condition would also dramatically effect the quality and characteristic of the acoustic pulse. The concentration of the oil itself would severely degrade the pulse.
    As an analogy, take your favorite 4 D Cell MagLite(R) and shine it to the bttom of your pool. OK its gets there, but widely diffused. Now imagine trying to shine it through a 5k ft column of bicycle reflectors. How far would that light get?

    • http://www.thehayride.com MacAoidh

      …is supposed to be effective in the midst of an explosion.

      Explosions have properties within the realm of acoustics, do they not?

  • Adjoran

    “In theory, theory and practice are the same. In practice, they aren’t.”

  • Warrior

    Obama has already given us the hope and change solution…

    • earlgrey
  • http://www.800cart.com Ron Robinson

    When I was a youngster in Oklahoma, I helped a lot at my Dad’s engineering biz – running blueprints and speccing vales, etc. – for the gasoline refineries and natural gas plants, etc he built. Got out in the oil patch a little. Learned to pull sucker rod, etc. You can learn a lot that way.

    Just enough to be dangerous.

    And the liberal bureaucrats ‘governing’ this disaster know much, much less (except that they can get porn and meth from some of their regulants [regulees?])

    So glad that you are giving us the real story here – you posts are informative and highly interesting to a guy like me! Keep it up!

  • dennism

    …called the device a “blowout protector” too and I started screaming at the screen that he was an idiot until they flashed a banner below his jowly face that said he was an ex-president of Shell Oil.

    Then realization washed over me like a viscous sludge… he’s trying to create equivalence in my brane and muddy my perception. He wants my unconsciousness to connect blowout preventers and pocket protectors. He’s saying ” hey, Dennism, it’s not there to PREVENT damage, it’s there to PROTECT against it.” I ain’t buying.

    Rhetoric is such great fun.

  • dennism

    …called the device a “blowout protector” too and I started screaming at the screen that he was an idiot until they flashed a banner below his jowly face that said he was an ex-president of Shell Oil.

    Then realization washed over me like a viscous sludge… he’s trying to create equivalence in my brane and muddy my perception. He wants my unconsciousness to connect blowout preventers and pocket protectors. He’s saying ” hey, Dennism, it’s not there to PREVENT damage, it’s there to PROTECT against it.” I ain’t buying.

    Rhetoric is such great fun.