Offshore passenger cat hull design

Discussion in 'Boat Design' started by CapeFisher, Feb 2, 2014.

  1. Mr Efficiency
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    Mr Efficiency Senior Member

    A whole bunch of people migrating to the side of the boat might not upset the overall stability calculation, but I'd not want to be carrying the public liability insurance when the thing heels over to 45 degrees and everyone goes aarse over apex ! The cat will have a much smaller heel angle than a monohull of similar carrying capacity. Nothing frightens tourists like a boat deck at a big angle to the horizon.
     
  2. Mr Efficiency
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    Mr Efficiency Senior Member

    OK, thanks for that info, I was wondering about that, but I guess the upside is the boat will pitch less in head seas. That boat is a pretty impressive platform for the job.
     
  3. eastcape
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    eastcape Senior Member

    Thank you, Mr. Efficiency.
     
  4. Ad Hoc
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    Ad Hoc Naval Architect

    Then it would not comply with statutory regulations. Max angle of list/heel under all possible conditions of loading is 10 degree.
     
  5. Mr Efficiency
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    Mr Efficiency Senior Member

    Well, if 10 degrees is the allowable limit, a 24 metre monohull would be restricted to a lot less than 245 paying passengers, would it not ?
     
  6. Ad Hoc
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    Ad Hoc Naval Architect

    Depends how the hull is designed and the layout of the public access.
     
  7. Mr Efficiency
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    Mr Efficiency Senior Member

    It is pretty clear to me that the 'whale watch' industry demands boats that can travel at around 20 knots or thereabouts, these are day tours and whales are where you find them, often a fair way from port, an extra hour travelling out, and another extra hour coming home, are two hours the customers don't get to see the whales. Slower boats are not competitive in that situation. Hell, I even got to see a Southern Right Whale and calf, in a very rare excursion close to the tropics, that a slow-coach boat would have missed, most likely. :D
     

  8. CapeFisher
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    CapeFisher New Member

    Whaling is all about speed and comfort. Most of the cats here run around 28-30kts cruising and some much faster. Our main focus is offshore fishing and naturally were more concerned with fuel consumption with the reduced passenger count. Also we run a longer season and are exposed to more weather, so good sea keeping qualities are a must.
     
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