|
|
From: SnJ - (no email)
Date: Tue Oct 02 2001 - 09:45:31 EDT
I have a question about this too. I have long known that LWL determines
maximum speed.
So what happens with a multihull? Does that mean a 36 foot catamaran's hull
speed is double that of a mono hull, and a Trimaran is triple the hull speed
of a monohull? Or is there some other act of physics involved?
Just curious.
>From: "mike senko" <>
>To: "Roger Crawford" <>
>CC: "liveaboard list" <>
>Subject: Re: lv-ab: Increasing speed
>Date: Mon, 1 Oct 2001 16:11:55 -0700
>
>Roger,
>
>Why do longer water line boats go faster?
>
>Wave making resistance is a constant.
>
>It takes more speed to build up the troughs that the longer water line boat
>cannot climb over (in flat water).
>
>Some designers think of it as "suction". The stern wave sucks the boat back
>and will not allow it to climb over the bow wave unless there is a LOT more
>horsepower available. So the shorter waterline boat will encounter its
>stern wave sooner and at a lower speed than the longer water line boat.
>
>Mike
> ----- Original Message -----
> From: Roger Crawford
> To: ; Live Aboard
> Sent: Monday, October 01, 2001 11:47 AM
> Subject: lv-ab: Increasing speed
>
>
> A few years ago when I owned a trimaran and was a member of "the Amatuer
>Yacht Building/Designing Group, one of their members claimed that by
>putting an half a wing at the top part of each side of the rudder (outboard
>rudder) just under water that it would kinda fool the boat into thinking it
>was longer and subsequently you would go faster. I tried it and I swear it
>worked. I think. My current boats rudder protrudes from the water under the
>counter. I could do the same thing and add a couple of feet to the water
>line length of my boat and the concurrent increase in speed. Anyone tried
>this or have any opinions. I don't think I ever heard (or at least
>understood) the physics behind why longer waterline boats go faster.
>
> Roger
> SV Yonder
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp
___________________________________________________________________________
|| The Live-Aboard List : send a "subscribe" or "unsubscribe" request ||
|| in body of message to: ||
|