Inclining Experiment

Discussion in 'Stability' started by Umair, Jun 7, 2021.


Inclination experiment for a small boat (10 m), what would you recommend to conduct in?

  1. Sea water

    3 vote(s)
  2. Air

    0 vote(s)
  1. Umair
    Joined: May 2020
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    Location: Pakistan

    Umair Junior Member

    I am going to conduct an inclining experiment for a small boat (10 m) around in length. I need the help of experts to know whether performing the test in sea water would give me satisfactory results? or suggest me to conduct it in air, if yes please guide me how to conduct it in air.

    Also I am not having data for displacements and drafts i-e stability booklet. How can I weight it and also how can I find the LCG?
  2. TANSL
    Joined: Sep 2011
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    Location: Spain

    TANSL Senior Member

    Are you clear about what the inclining test is carried out for?
    That, along with the height of the CoG is what you will find out from the inclining test.
    The weight of the boat, at the time of the test, will be deducted by taking note of the drafts in the bow and the stern at the time of the test. With these drafts, together with the hydrostatics of the boat with the corresponding trim, which you must have previously calculated, you will deduct the displacement (weight) of the boat at that moment.
  3. Heimfried
    Joined: Apr 2015
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    Location: Berlin, Germany

    Heimfried Senior Member

    Without displacement data and proper drawings of the hull shape an inclining experiment in water is useless.
    If you are able to do the experiment in air it will give you the data you need.
    This thread will inform you procedure for an inclining experiment in air
    #35 provides a pdf with explanation of the i e in air (note the faulty formula).
  4. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    If that is all you seek, it is very straight forward.
    You place 4 load cells, 2 aft P&S and 2 fwd P&S.
    You physically weight the boat, and the 4 load cells will give you the weight & the LCG.

    I've done this endless times...
    Last edited: Jun 7, 2021
    DogCavalry likes this.

  5. Don92
    Joined: Feb 2015
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    Location: Glasgow

    Don92 Principal Naval Architect

    I agree entirely with Ad Hoc, tried and test method!
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