Re: [PSUBS-MAILIST] Calculating Hull Speeds

["Joop Dresscher" <jadresscher@chello.nl>]

 

http://www.users.globalnet.co.uk/~fsinc/yachts/spreads/fred.htm shows the steep peek in wavedrag

http://www.zwakenberg.de/hulldrag/ also has some stuff

thats why i'm making this http://foxxaero.homestead.com/indrad_062.html

 

happy holliday's all

yipster

 

 

----- Original Message -----

From: David Buchner

To: personal_submersibles@psubs.org

Sent: Friday, December 24, 2004 3:38 PM

Subject: Re: [PSUBS-MAILIST] Calculating Hull Speeds

On Tuesday, Dec 21, 2004, at 16:57 US/Central, SeaLordOne@aol.com wrote:

The wires are pretty slow lately, so perhaps I will toss in one of those Boating 101 facts not everyone may know.  There are two basic hull types: planing hulls that can ride over the water, and displacement hulls that cut through the water. If you have a planing hull, more power can get you more speed.  But if you have a displacement hull, like submarines do, your speed (on the surface) is limited by your length.

Just wanted to say that this was fascinating -- definitely one of those non-intuitive things.

And ask a question that'll reveal me to be a bit thick:

Where does the extra power go, if it wouldn't make you faster?