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    Re: paragraph on gyros
    From: Lu Abel
    Date: 2012 Aug 17, 13:06 -0700
    This sounds to me a bit like "marketing to a not very knowledgeable reporter"   

    Most oceangoing liners use fin-type stabilizers projecting from the side of their hull.  These are not just fixed fins.  Rather a signal from a (small) gyro is used direct electric motors to move the fin so it will resist the roll that the ship is about to take.

    This article seems to say "hey, you don't need fins, just make the gyro big enough."  True, but the larger the gyro, the less space you have for useful stuff like passengers or cargo. 

    There are some experiments going on with very high speed gyros as energy storage mechanisms.   I think there is at least one European city that is experimenting with powering its public transit buses using gyros instead of batteries.   I believe they have to be "charged" about every half hour (but that can be done more rapidly than charging a storage battery).   It's possible that such a very high-speed gyro could also be used for direct gyroscopic stabilization of a ship.   But gyro-controlled fins are a long-time, proven technology.  And I don't believe they require much power as compared to the ship's propulsion itself.   So gyro-alone stabilization will have an uphill fight to replace a low-cost, proven technology.

    From: Robert Wyatt <chupacerveza@gmail.com>
    To: NavList@fer3.com
    Sent: Friday, August 17, 2012 11:17 AM
    Subject: [NavList] paragraph on gyros

    A very brief reference to gyros in Sea Magazine:

    Gyros Deliver Stability

    Posted: August 1, 2012
    By: Roger McAfee
    It sure does. Gyro stabilizers operate on the principle that a spinning mass resists efforts to move it in any direction. As kids, we used to play with a spinning top. Once the top got spinning, the surface on which the top was spinning could be moved, tilted and angled, but the top continued to spin in a vertical position. This is a gross oversimplification of modern gyro stabilizers, but it makes the point. In 1922, a 120-ton gyro stabilizer was installed on an oceangoing passenger liner, Hawkeye State, operating between Baltimore and Honolulu. Modern gyros can be fitted on outboard-powered boats as small as 40 feet.
    Unlike fin stabilizers, gyros work whether the vessel is at rest or under way, and there are no through-hull fitting requirements.

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