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The mysterious world of measurements…

Discussion in 'General Yachting Discussion' started by Pascal, Feb 19, 2025.

  1. Pascal, Feb 19, 2025
    #1
    Pascal

    Pascal Senior Member

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    Amazing how boat measurements seem to work…

    An Ocean Alexander 116 UHV just docked in front of us and out of curiousity I looked it up. It s listed by OA at 116’ with a beam of 25’ and a GT of 199.

    we are 110’ with a beam of 22’ but are 211 GT! Oh and our COD shows a length of 97’…

    go figure…
  2. Capt Ralph, Feb 19, 2025
    #2
    Capt Ralph

    Capt Ralph Senior Member

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    Have you measured your hull yourself? That 110' may not include the elevator and maybe the pulpit if molded with the hull.
    Sales folk luv LOA but not a true molded hull length.
    That OA's COD may have different numbers also vs real molded hull data.
    Gross tonnage is internal volume. These numbers can be adjusted also. ie; your enclosed bridge vs a canvas covered flybridge.

    Another example, that real pointed nose on the ole Fountains was usless but still LOA and priced that way.
  3. Pascal, Feb 19, 2025
    #3
    Pascal

    Pascal Senior Member

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    Hull is 110, plus a 6’ in platform
  4. Capt J, Feb 20, 2025
    #4
    Capt J

    Capt J Senior Member

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    Gross tonnage is also effected by areas that have doors or hatches to the exterior and all sorts of other tricks they use on commercial boats to keep tonnage down. Most of those 100-150' dinner party boats are 99 GRT. LOL
  5. Pascal, Feb 20, 2025
    #5
    Pascal

    Pascal Senior Member

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    Do you mean like these huge windows in the hull?
  6. captholli, Feb 20, 2025
    #6
    captholli

    captholli Senior Member

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    Google "tonnage doors on yachts"
  7. BlueNomad, Feb 22, 2025
    #7
    BlueNomad

    BlueNomad Senior Member

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    If either/both are classed yachts, the rule length may be 96% of the length on a waterline at 85% of the least moulded hull depth, measured from the top of the keel ;)
  8. German Yachting, Feb 24, 2025
    #8
    German Yachting

    German Yachting Senior Member

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    I’m struggling to find the OA model you are mentioning. If it is a new one, the 98’ are 208gt and the larger ones at a 116’ range are between 270-299 that have the 25’ beam.