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Combine gyro and fin stabilizers

Discussion in 'Stabs, Tabs & Gyros' started by Northwind, Jan 20, 2017.

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  1. Northwind

    Northwind Member

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    This is an effort to resurrect a previous post that drifted off topic.

    A group of posters suggested that combining gyro and active fin stabilizers might be the best answer for a large but slow moving boat.

    In my experience, any time you hire two vendors to share a project, each blames the other for problems. So, how would you define and manage a stabilizer project that relies on two different technologies? Any ideas how you would allocate your expectations?

    Thank you.
  2. Capt J

    Capt J Senior Member

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    I don't see the need for both on a slow boat. One system will work to stabilize it.

    The 2 stabilizers are generally on faster yachts, the seakeeper makes the most difference at hull speed. On plane they're marginally effective where the fins are a lot more effective so then you use the fins.
  3. German Yachting

    German Yachting Senior Member

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    Why can't fins be be one solution if they can act as one on a slower boat?
  4. olderboater

    olderboater Senior Member

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    They can be but not the way it appears to be trending. Now one of the reasons I think is to avoid going to larger fins on a faster boat. Fit, draft, and loss of performance would become a factor with larger fins.
  5. Capt J

    Capt J Senior Member

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    They could be. The OP did mention that effectiveness while the vessel is anchored or at rest. Now, zero speed stabilizers work pretty well in this mode, but seakeepers really shine. Now, the OP mentions he wants no hydraulics, well there goes the option of good zero speed stabilizers. Back to the seakeeper it is which is electric and no hydraulic system to install. You do need a seawater cooling pump, but that is what it is and so does a hydraulic system.
  6. K1W1

    K1W1 Senior Member

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    I am of the understanding that the slamming of fins once they clear water and re enter is often too much for the hydraulics

    We have a yacht with a Seakeeper and Humphree interceptors. Initial experiences with it are very good.
  7. Capt J

    Capt J Senior Member

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    On vessels that are really fast, launching the hull out of the water and back into the water can be an issue for fins. More so that it can actually sheer the fin from the shaft it's mounted on. Humphrees so far seem to work well in that application. (Arneson boats, jet boats, etc.)

    On motoryachts and sportfish that cruise around up to 30-35 knots, seems to be no issue for the fin style stabilizers, but may lose speed with them.
  8. Gratton

    Gratton Member

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    Not sure how large you mean by "large but slow moving boat" but I know some Azimut Magellano 53 have both a seakeeper and some fins stabilization.
  9. olderboater

    olderboater Senior Member

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    I believe the Magellano 53 is like I've seen with a lot of boats recently. The fin stabilizers are standard and the gyros are an option ($125,000 or so on the Magellano) but they don't eliminate the fins when they add the gyros as both have their benefits. It's not gyro in lieu of fins, but in addition to.
  10. German Yachting

    German Yachting Senior Member

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    Somewhat on the topic of combining fins and gyros, what’s the benefit of having two gyros installed? For example, the L650 comes with two standard and some sportfishers are being retrofitted with two whereas new build Vikings generally only have 1. Is it more so the engineering being done at the forefront to minimize the need for a second and advances in the technology?
  11. captholli

    captholli Senior Member

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    2 x the spinning mass & inertia seeking the axis of the earth.
  12. Capt J

    Capt J Senior Member

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    More effective. More ability to mount them in different places than just on centerline.