How to get the LOA of the ship?

[Laranjo123]

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?

[FMS]

Originally Posted by Laranjo123

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?

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.

[gonzo]

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.

[jehardiman]

Originally Posted by gonzo

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.

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.

[Laranjo123]

My prof said there was no ruling for LOA it depends on the NAVAL, it depends on his design? is that true?

[hoytedow]

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:

[DCockey]

Originally Posted by Laranjo123

My prof said there was no ruling for LOA it depends on the NAVAL, it depends on his design? is that true?

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.

[jehardiman]

Originally Posted by DCockey

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.

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.

[Laranjo123]

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

[gonzo]

The first formula doesn't correspond to the second. Please be consistent.

[peter radclyffe]

it may not include spars
http://en.wikipedia.org/wiki/Length_overall

[Poida]

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

[philSweet]

Defining this term accurately is not to anyone's advantage. As long as the def. is murky, it is negotiable. Please cease and desist.