Boat Building Forum

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Re: The Long Boat Myth
By:Nick Schade - Guillemot Kayaks
Date: 6/10/2009, 8:49 am
In Response To: Re: The Long Boat Myth (Kudzu)

: I have to disagree with that. If I change beam and the length then I don't
: have a fair comparison. I would be comparing an apple to an orange. By
: changing only one factor, in this case length of the hull, I know any
: change in the resistance numbers are because of the change in the length.
: Nothing else.

I agree with the principle, but if you are not holding displacement constant, then you are changing the most important factor. Changing the length without changing the width or draft will effect displacement.

I would change the length and then adjust where the boat floats until the displacement is matched. With a typical boat this will mean the boat floats higher with a the result that the waterline width and draft change. I don't know how Free!Ship handles this but some Naval Architecture software will automatically find the equilibrium condition for a given displacement and can use that for the drag predictions.

Messages In This Thread

Skin-on-Frame: Fast, Playful SOF *Pic*
Michael Collins -- 6/8/2009, 11:10 pm
Re: Skin-on-Frame: Fast, Playful SOF
Aaron H -- 6/9/2009, 3:36 pm
Re: Skin-on-Frame: Fast, Playful SOF
Michael Collins -- 6/9/2009, 10:39 pm
Re: Skin-on-Frame: Fast, Playful SOF
Aaron H -- 6/10/2009, 6:11 pm
Re: Skin-on-Frame: Fast, Playful SOF
Brian Scaborough -- 6/10/2009, 10:21 am
Re: Skin-on-Frame: Fast, Playful SOF
John D. -- 6/10/2009, 3:02 pm
The Long Boat Myth *LINK* *Pic*
Kudzu -- 6/9/2009, 7:43 pm
Re: The Long Boat Myth
Mike Savage -- 6/11/2009, 7:01 pm
Re: The Long Boat Myth
Johne -- 6/11/2009, 12:08 pm
Re: The Long Boat Myth
Michael -- 6/11/2009, 10:23 am
Re: The Long Boat Myth *Pic*
Allan -- 6/11/2009, 3:54 am
Re: The Long Boat Myth
Bill Hamm -- 6/11/2009, 9:50 am
Re: The Long Boat Myth
Kudzu -- 6/11/2009, 11:56 am
Re: The Long Boat Myth
Michael Collins -- 6/11/2009, 1:58 pm
Re: The Long Boat Myth
Kudzu -- 6/11/2009, 5:33 pm
Re: The Long Boat Myth
Bill Hamm -- 6/13/2009, 1:23 am
Re: The Long Boat Myth
Terry Haines -- 6/18/2009, 11:45 pm
Re: The Long Boat Myth
Bill Hamm -- 6/19/2009, 11:39 am
Re: The Long Boat Myth
John F Monroe -- 6/24/2009, 5:42 am
Re: The Long Boat Myth
Terry Haines -- 6/19/2009, 6:33 pm
Re: The Long Boat Myth
Bill Hamm -- 6/11/2009, 1:26 pm
Re: The Long Boat Myth
Kudzu -- 6/11/2009, 7:42 am
Re: The Long Boat Myth
Allan -- 6/11/2009, 8:02 am
Re: The Long Boat Myth
Kudzu -- 6/11/2009, 9:19 am
Re: The Long Boat Myth
West -- 6/11/2009, 4:23 am
Re: The Long Boat Myth
Allan -- 6/11/2009, 7:45 am
Re: The Long Boat Myth
Ken Brunton -- 6/10/2009, 11:13 am
Re: The Long Boat Myth
Kudzu -- 6/10/2009, 1:40 pm
Re: The Long Boat Myth
Michael Collins -- 6/10/2009, 2:16 pm
Re: The Long Boat Myth
Kudzu -- 6/10/2009, 7:52 pm
Re: The Long Boat Myth
Bill Hamm -- 6/10/2009, 3:44 pm
Re: The Long Boat Myth
Michael Collins -- 6/9/2009, 10:26 pm
Re: The Long Boat Myth
Kudzu -- 6/10/2009, 8:33 am
Re: The Long Boat Myth
Nick Schade - Guillemot Kayaks -- 6/10/2009, 8:49 am
Re: The Long Boat Myth
Kudzu -- 6/10/2009, 1:08 pm
Re: The Long Boat Myth
Nick Schade - Guillemot Kayaks -- 6/11/2009, 10:35 am
Hey Nick
Kudzu -- 6/12/2009, 10:18 am
Single change??
Allan -- 6/12/2009, 6:47 pm
Re: The Long Boat Myth
Kudzu -- 6/11/2009, 12:04 pm
Re: The Long Boat Myth
Glen Smith -- 6/9/2009, 8:16 pm
Re: The Long Boat Myth
Kudzu -- 6/10/2009, 8:17 am
Re: The Long Boat Myth
Nick Schade - Guillemot Kayaks -- 6/10/2009, 8:57 am
Re: Skin-on-Frame: Fast, Playful SOF
Bill Hamm -- 6/9/2009, 1:15 am
Re: Skin-on-Frame: Fast, Playful SOF
Brian Scaborough -- 6/9/2009, 8:32 am
Re: Skin-on-Frame: Fast, Playful SOF
wwfloyd -- 6/10/2009, 7:47 pm
Re: Skin-on-Frame: Fast, Playful SOF
Bill Hamm -- 6/11/2009, 1:00 am
Re: Skin-on-Frame: Fast, Playful SOF *LINK* *Pic*
Tom Yost -- 6/9/2009, 10:24 am
Re: Skin-on-Frame: Fast, Playful SOF
Bill Hamm -- 6/9/2009, 8:28 pm
Re: Skin-on-Frame: Fast, Playful SOF
Tom Yost -- 6/10/2009, 12:41 am
LMAO!
Robert N Pruden -- 6/9/2009, 2:43 pm
Re: LMAO! *Pic*
Tom Yost -- 6/9/2009, 6:13 pm
Re: LMAO!
Bill Hamm -- 6/9/2009, 8:30 pm
Re: Skin-on-Frame: Fast, Playful SOF
Brian Scaborough -- 6/9/2009, 10:40 am
Re: Skin-on-Frame: Fast, Playful SOF
Michael Collins -- 6/9/2009, 11:11 pm
Re: Skin-on-Frame: Fast, Playful SOF
Brian Scaborough -- 6/10/2009, 1:00 pm
Balancing Gear
Michael Collins -- 6/10/2009, 2:01 pm
Re: Balancing Gear
Bill Hamm -- 6/10/2009, 3:40 pm
Re: Balancing Gear *LINK*
Brian Scaborough -- 6/10/2009, 2:27 pm
Re: Skin-on-Frame: Fast, Playful SOF *Pic*
Tom Yost -- 6/9/2009, 11:01 am
I've done that, too, but only with the Guinness.
Robert N Pruden -- 6/9/2009, 2:46 pm
Re: Skin-on-Frame: Fast, Playful SOF
Brian Scarborough -- 6/9/2009, 12:00 am
Rider, Ranger?
Michael Collins -- 6/9/2009, 11:07 pm
Re: Rider, Ranger?
Bill Hamm -- 6/10/2009, 2:27 am