Trimaran design help needed 40' LOA

[eightwgt]

I am looking for help for a power trimaran of the ILAN type hull.
Design Criteria :

40' LOA
Shallow draft
Low resistance hull
Narrow overall beam
outboard powered (for shoal draft situations / beaching)
Cold molded construction
Sleeps 4-6 (yes I know it will be tight)

Please email me at eightwgt@aol.com

Tom

[Eric Sponberg]

Tom,

What type of help do you need? Are you designing this boat yourself, or do you want someone to design it for you? Are you looking for a custom design or a stock design?

Eric Sponberg

[eightwgt]

Eric

I want help, or someone to design. I am a capable designer, and have maxsurf and autocad however I have no experiance with this type vessel

Tom

Most objects like this are cats.

A power tri is generally a narrow hull with "training wheels" and there has to be some very special circumstances for this configuration to be optimum.
Usually the short side hulls produce more drag than if they were in an equivalent single side hull, because they are at a higher Froude number.
You may want to look at some papers from ASNE or the various "Fast" symposia. Doctors has a good one in Fast '99 or 2001 on the number of hulls debate.
There is also a very big book resently published on multihulls by a group of Russians. It is fairly expensive, but quite complete.

[eightwgt]

Well since posting I have decided on a cat for many reasons. I am trying to find a design that may easily be converted to a power cruiserthat could be powered with 2 50 Hp 4 stroke outboards and get a cruisinf speed of about 12-15 knots
ANY suggestions ??

[Guardian]

Quote"There is also a very big book resently published on multihulls by a group of Russians. It is fairly expensive, but quite complete." /Quote Do tell what is the name of this book ? and where can I/ we get it ?


Thanks,
-Mike

[Leo Lazauskas]

The program "Michlet" will allow you to get some estimates of (calm-water) resistance of trimarans. See:

www.cyberiad.net/michlet.htm

Michlet will also allow you to optimise for drag (and for other factors).

All the best,
Leo.