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Virtual Earth Exposes Nuclear Sub's Secret

NewsCloud alerts us to a story a few months old that has been getting a lot of play recently. A Seattle blogger, Dan Twohig, was browsing in Microsoft's Virtual Earth when he accidentally came across a photo of a nuclear sub in dry-dock. Its propeller is clearly visible — this was a major no-no on the part of someone at the Bangor Sub Base. The designs of such stealth propellers have been secret for decades. Twohig blogged about the find and linked to the Virtual Earth photo on July 2. The debate about security vs. Net-accessible aerial photography has been building ever since. The story was picked up on military.china.com on Aug. 17 — poetic justice for the Chinese sub photo that had embarrassed them a month before. On Aug. 20 the Navy Times published the article that most mainstream media have picked up in their more recent coverage. Twohig's blog is the best source to follow the ongoing debate. No one has asked Microsoft, Google, or anyone else to blur the photo in question. Kind of late now.

6 of 355 comments (clear)

  1. Re:Slashdot by jmauro · · Score: 4, Interesting

    Or it's a fake plant to hide the real propeller design.

  2. Re:Link to base since the blog is hosed by BCW2 · · Score: 4, Interesting

    Think again! 99.9% of the Navies of the world don't have sonar good enough to even get a sniff of one of our boats. The best the Soviets ever had was 2 generations behind! There is supposed to be a canopy over the the screw before the dock is pumped out. If you ever go to Groton for a launch you might notice that the boats are launched without a screw, it is installed later alongside the pier. Of course there are 2 different screws for each class of boats. A speed screw is used on the first few to generate top performance numbers then removed. A silent screw goes on all operational boats. The difference? Shape, pitch, and number of blades.
    I rode a Fast Attack in the Cold War, so I might know more than someone who hasn't been there.

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  3. Re:Is it really so secret? by ScrewMaster · · Score: 4, Interesting

    It was a machine tool made by a subsidiary of Toshiba (Toshiba Machine Co.) and a Norwegian numerical controller that were sold to Russia. This page has a good writeup. The sale was made in direct contravention to Japanese export controls with full knowledge of the people running the company. If the numbers are to be believed, Toshiba Machine's 17 million dollar sale cost the U.S. thirty billion in lost military superiority. This technology is important, actually.

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  4. Re:The US Navy Is Not Such A Secret by Jarjarthejedi · · Score: 5, Interesting

    "In a war against a major enemy, carriers will probably be useless..."

    And where did that factoid come from? One would imagine that a ship with the capability to strike at extremely long distances is always useful, if you can hit your enemy before their weapons can reach you you have an advantage. As for carriers being vulnerable to subs that's only partially true. Certain types of submarines, especially advanced nuclear subs (and diesel ones, so long as they don't surface anywhere near the carrier group and have enough battery power to get in and out) could conceivably slip through the defenses around a carrier and then it's aircraft would be useless. Given that the last major (that I know of) engagement between large groups of submarines and carriers was WWII, and that was clearly decided in favor of the carrier groups (53 u-boats sunk to less than 10 of the CVE mini-carriers) I'd say a generalization like 'Subs counter carriers' is kinda...wrong. A carrier battle group at war would typically have at least 1 radar plane (Orion?) on CAP. If the sub surfaces nearby radar has a chance of picking it up. In addition the carrier's escorts have darn good sonar and wouldn't be too hesitant to use it.

    So basically, 1 lone carrier vs sub is an easy win for the sub, unless the carrier sees it coming from a long way off and launches anti-sub efforts. 1 carrier battlegroup is at least a match for any similar number of warships, including subs, and very good at other tasks such as beach assault, long range support etc. A carrier battle group is currently the most versatile type of navy imaginable, as such it may not be the best way to counter all threats (a pair of destroyers working in tandem with some anti-sub helicopters would be cheaper and pretty effective against small numbers of subs). It's a Jack of All Trades, master of none type of thing, a Carrier group is good at anti-surface ship, anti-sub, and anti-land combat.

    Sneaking up on a ship which is fully prepared for war is a lot harder than some things would lead you to believe. Just because you're underwater and pretty quiet doesn't mean your undetectable, and if you're too quiet you can be detected that way (one possibly problem with modern US subs is that they're actually quieter than the surrounding ocean and could *conceivably* be detected that way). No amount of noise-reduction is going to save you if even 1 enemy ship is using active-sonar, you're going to be detected unless it's a cloak-and-dagger fight which is something aircraft carriers rarely engage in, they're more 'Hey look, I'm right here, I don't need to hide because I'm that much better than you' style fighting, and in that arena (when radars are at full and sonars are active) subs lose all stealth benefits, and an unstealthed sub vs a carrier group is just asking for trouble.

    So to sum it up, no, a carrier battle group is not useless. Subs are easily countered (unless you're trying to be stealthy as well) and missile blocking is what Aegis (common in CBG's) class destroyers were partially built for. Aircraft carriers are built for show, and are good against weaker enemies, but also against equals, it's against stronger enemies (few and far between at this moment) that they begin to look impossibly weak and fragile.

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  5. Re:Probably not significant by Anonymous Coward · · Score: 4, Interesting

    My guess is that a quiet high-thrust propeller would spin slowly and have many, very wide and heavily-curved blades. Let's see if somebody who knows more agrees.
    This is basically the case and you can prove it by looking at any modern airliner. A modern high-bypass turbofan jet engine is really just a turbine-driven ducted propellor, and the propellor geometry is much like what you describe, with a whole ton of blades spinning at a reasonable speed.

    Next time you get on a 777, just think, you are riding on one of the most advanced propellor aircraft in the world.
  6. Re:The US Navy Is Not Such A Secret by Comatose51 · · Score: 4, Interesting

    Hate to break it to you but the Swedish sub, Gottland has managed to "sink" the USS Reagan before in a war game simulation. The US Navy's defense against diesel electric sub is not that perfect.

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