How to get the LOA of the ship?

Discussion in 'Boat Design' started by Laranjo123, Sep 26, 2011.

  1. Laranjo123

    Laranjo123 Previous Member

    Hello i just want to ask about how to get the LOA of the ship? Is there any formula existing for this? Is there any percent to where i can use?
     
  2. FMS
    Joined: Jul 2011
    Posts: 611
    Likes: 22, Points: 18, Legacy Rep: 227
    Location: united states

    FMS Senior Member

    Your question is too general to make sense.
    Length overall will be defined by the requirements of and limitations imposed upon the boat in question.
     
  3. gonzo
    Joined: Aug 2002
    Posts: 16,817
    Likes: 1,726, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    LOA is the measurement between verticals of the whole ship including appendages, etc. You don't use a formula but a measuring tape or other device.
     
  4. jehardiman
    Joined: Aug 2004
    Posts: 3,776
    Likes: 1,171, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Gonzo is absolutely correct here, LOA is independent of all other parameters.

    Now, if you are concerned with Length on WaterLine (LWL), there are some rules of thumb if you know the ship type and tonnage.
     
  5. Laranjo123

    Laranjo123 Previous Member

    My prof said there was no ruling for LOA it depends on the NAVAL, it depends on his design? is that true?
     
  6. hoytedow
    Joined: Sep 2009
    Posts: 5,857
    Likes: 400, Points: 93, Legacy Rep: 2489
    Location: Control Group

    hoytedow Carbon Based Life Form

    No matter what the design or who designed it, the terminology holds true..
    LOA is total length of boat including any fixture/attachment projecting beyond hull itself.
    LWL is length of boat at the waterline at rest or moving, variable with load/hull type/speed etc.
    Beam is width of hull.

    See sketch:
     

    Attached Files:

  7. DCockey
    Joined: Oct 2009
    Posts: 5,229
    Likes: 634, Points: 113, Legacy Rep: 1485
    Location: Midcoast Maine

    DCockey Senior Member

    Depends on the constraints and objectives for the design, and how the design was generated.

    For example, if a vessel will need to go through locks then it's LOA has to be short enough to fit into the lock.

    If there are no constraints on LOA and the designer starts with a set design LWL, then LOA will be the result of various decisions made during the design process.
     
  8. jehardiman
    Joined: Aug 2004
    Posts: 3,776
    Likes: 1,171, Points: 113, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Absolutely true.

    Laranjo123, often the naval architect is given a "design box" which he cannot excede. This may include maximum LOA, maximum Beam, maximum Draft, maximum Air Draft, maximum Tonnage, etc., and any combination of these.

    So a designer who is given the task to make a 7,000 TEU container ship may be limited by a maximum terminal crane reach of 110 feet, which sets the beam. For arrangement and powering reasons he wants a LWL to Beam of ~10 for a LWL of 1100 feet and a LOA of ~ 1155 ft. If he then gets a operational limit, such as a requirement to transit the Panama canal, he may have reduce LWL because of the 1,000 ' LOL limit of the locks and increase Draft to make up for the lost tonnage.

    LOA often depends on the design brief, not any particular relationship between hull dimensions.
     
  9. Laranjo123

    Laranjo123 Previous Member

    What I did was LOA/LBP=loa/lbp big letters are for parentship and small letters for models. like 46/41 = LOA/ 40 is this correct i'm just using my parentship's length ratios?..
    BTW thank you for sharing your exp. I really appreciate your helps. hehe
     
  10. gonzo
    Joined: Aug 2002
    Posts: 16,817
    Likes: 1,726, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    The first formula doesn't correspond to the second. Please be consistent.
     
  11. peter radclyffe
    Joined: Mar 2009
    Posts: 1,454
    Likes: 72, Points: 58, Legacy Rep: 680
    Location: europe

    peter radclyffe Senior Member

  12. Poida
    Joined: Apr 2006
    Posts: 1,188
    Likes: 51, Points: 48, Legacy Rep: 497
    Location: Australia

    Poida Senior Member

    The plot thickens.

    LOA according to Gonzo means the total length of a boat and you simply measure it.

    Peter Radcliffe points us to a Wikki page that confirms this.

    Where are all these formulas coming from?

    One confused Poida
     

  13. philSweet
    Joined: May 2008
    Posts: 2,697
    Likes: 461, Points: 83, Legacy Rep: 1082
    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    Defining this term accurately is not to anyone's advantage. As long as the def. is murky, it is negotiable. Please cease and desist. :D
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.