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Aggressive Yaw/Roll on Ocean 66SS with following seas

Discussion in 'Ocean Yacht' started by SMR-PILOT, Feb 1, 2015.

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  1. SMR-PILOT

    SMR-PILOT Member

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    Location:
    Santa Marta, Colombia
    So I´ve had this boat for a while now. I removed the jet ski from the bow (the dinghy doesn´t weigh that much), had the tanks at about 40% and had a really rough time last weekend with following seas once again. I was actually running at cruising speed, about 22 knots. Is is safer to run at lower speeds in following seas? this wave caught me off guard and had me roll excessivelly, scaring all my passengers.... original engines on this boat were 12V92s which are heavier than the cats 3412s, I wonder if this has anything to do with this stability issue.
  2. Capt J

    Capt J Senior Member

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    Quite possibly. The Oceans can be a little scary in a following sea. The more weight in the stern of the boat the better, full fuel makes quite a difference. Should try filling the livewell and fish boxes with saltwater (to the top) with the washdown hose and try. You don't want the water sloshing around either.
  3. RT46

    RT46 Senior Member

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    SMR,

    just wondering, did the repower change position of the mains, are they more forward? are the gears longer?

    the less weight on the bow the better.
    What kind of tender do you have?

    are you tanks on center? if so, try moving fuel to keep the weight in the aft tank.
    The same with the water tanks, if on center, try to keep the aft tank full.

    EDIT:
    I just went back and looked at the pics, you have too much stuff on the bow of your boat.
    you could go a lot lighter on the tender also.
    Last edited: Feb 15, 2016
  4. RT46

    RT46 Senior Member

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    are the new Mains higher?
  5. Trinimax

    Trinimax Senior Member

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    Trinidad and Tobago Yacht club
    Hi SMR
    with regards to your running speed. The ocean 43 I run has a dinghy on the bow and even with the tabs full up, the bow doesn't start to rise properly till I cross 21 knots and will rise more as the speed increases. For instance at 18 knots the boat is on plane but runs pretty level with tabs right up. So depending on the size of the following sea, running at higher speeds should improve your performance and reduce the negative effects.

    Hope this helps
  6. docjr03

    docjr03 New Member

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    What was the sea state? Were they big rollers or was the wind high; blowing whitewater off the tops of the waves?
  7. SMR-PILOT

    SMR-PILOT Member

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    Location:
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    about 15 knot winds and big rollers on the starboard quarter, I was also passing through an area with strong currents.
  8. SMR-PILOT

    SMR-PILOT Member

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    Location:
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    Yeah that´s what I thought, I was trying to run ahead of the wave and I was making 22 knots. the wave started catching my starboard quarter so I sped up an turned quickly to port but the wave still had me sway quickly to starboard and then roll heavily to port. Loose objects were all over the place down below. Thanks for your input.
  9. ychtcptn

    ychtcptn Senior Member

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    I ran a few down Easter's in my day and some of them were down right scary going down sea, the JC 31 for example. We found that a big difference was the size of the keel/skeg on some of these boats, less was better. Not sure what the bottom of your boat looks like, but maybe this could be an issue.
  10. ychtcptn

    ychtcptn Senior Member

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    I ran a few down Easter's in my day and some of them were down right scary going down sea, the JC 31 for example. We found that a big difference was the size of the keel/skeg on some of these boats, less was better. Not sure what the bottom of your boat looks like, but maybe this could be an issue.
    Howard White likes this.