Boat Building Forum

Find advice on all aspects of building your own kayak, canoe or any lightweight boats

Re: Other: advice on tandem sea kayak designs
By:Nick Schade - Guillemot Kayaks
Date: 12/5/2013, 4:50 pm
In Response To: Re: Other: advice on tandem sea kayak designs (Allan)

On another forum, I provided an illustration of how two kayaks with the same width could have very different levels of stability. In fact one could have four times the righting moment without changing the width.

I like to say that it is the "Distribution of Width" at the waterline that determines initial stability. Two boats with the same waterline width, but different water plane coefficients, will have different stabilities. Waterplane coefficient is the area of the water plane divided by the area of a rectangle the waterline length and waterline beam. Higher coefficients are closer to a rectangle and have relatively more parts of the boat that are wide than lower coefficients.

Secondary stability is more a function of overall width as well as overall volume and a similar shape coefficient could be described that shows a similar higher stability for boxier shapes.

Messages In This Thread

Other: advice on tandem sea kayak designs
mike_c -- 11/30/2013, 9:18 pm
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 11/30/2013, 10:47 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/1/2013, 12:20 am
Re: Other: advice on tandem sea kayak designs
scottbaxter -- 12/1/2013, 1:24 am
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/6/2013, 10:49 am
Re: Other: advice on tandem sea kayak designs
Marc Upchurch -- 12/6/2013, 12:39 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/7/2013, 11:45 am
Re: Other: advice on tandem sea kayak designs
Marc Upchurch -- 12/7/2013, 12:12 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/8/2013, 12:13 am
Re: Other: advice on tandem sea kayak designs *PIC*
Rob Macks/Laughing Loon CC&K -- 12/1/2013, 11:55 am
Re: Other: advice on tandem sea kayak designs
Ric Moodie -- 12/1/2013, 11:57 am
Re: Other: advice on tandem sea kayak designs
aedie -- 12/1/2013, 2:30 pm
Re: Other: advice on tandem sea kayak designs *PIC*
Etienne Muller -- 12/1/2013, 2:43 pm
Re: Other: advice on tandem sea kayak designs
JohnAbercrombie -- 12/1/2013, 3:23 pm
Re: Other: advice on tandem sea kayak designs
Nick Riccardi -- 12/1/2013, 3:54 pm
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/1/2013, 6:43 pm
Re: Other: advice on tandem sea kayak designs
Nick Riccardi -- 12/2/2013, 10:56 am
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/3/2013, 12:20 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/3/2013, 12:29 am
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/4/2013, 12:24 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 10:11 am
Re: Other: advice on tandem sea kayak designs *PIC*
Rob Macks/Laughing Loon CC&K -- 12/4/2013, 11:13 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 1:23 pm
Re: Other: advice on tandem sea kayak designs
Marc Upchurch -- 12/4/2013, 1:32 pm
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 1:49 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/5/2013, 2:21 am
Re: Other: advice on tandem sea kayak designs
Paul Davies -- 12/4/2013, 3:33 pm
Re: Other: advice on tandem sea kayak designs
Etienne Muller -- 12/4/2013, 3:48 pm
Re: Other: advice on tandem sea kayak designs
Paul Davies -- 12/4/2013, 4:32 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/5/2013, 2:33 am
Re: Other: advice on tandem sea kayak designs
Mike Bielski -- 12/4/2013, 6:57 pm
Re: Other: advice on tandem sea kayak designs
Bill Hamm -- 12/5/2013, 2:14 am
Re: Other: advice on tandem sea kayak designs
Allan -- 12/5/2013, 5:25 am
Re: Other: advice on tandem sea kayak designs
Etienne Muller -- 12/5/2013, 1:52 pm
Re: Other: advice on tandem sea kayak designs
Nick Schade - Guillemot Kayaks -- 12/5/2013, 4:50 pm
Re: Other: advice on tandem sea kayak designs
ancient kayaker -- 12/5/2013, 6:24 pm
thanks for the advice so far!
mike_c -- 12/1/2013, 5:00 pm
Re: thanks for the advice so far! *PIC*
Paul Davies -- 12/1/2013, 7:44 pm
Re: thanks for the advice so far!
Rob Macks/Laughing Loon CC&K -- 12/2/2013, 5:33 pm
Re: thanks for the advice so far!
Paul Davies -- 12/2/2013, 8:28 pm
Re: thanks for the advice so far!
Nick Riccardi -- 12/4/2013, 6:19 pm
Re: thanks for the advice so far! *PIC*
Kyle T -- 12/2/2013, 9:09 am
Re: thanks for the advice so far! *PIC*
Sean Dawe -- 12/2/2013, 12:45 pm
Re: thanks for the advice so far!
Dan Caouette (CSCWC) -- 12/2/2013, 1:16 pm
Re: thanks for the advice so far!
ancient kayaker -- 12/2/2013, 5:08 pm
Re: thanks for the advice so far!
Bill Hamm -- 12/3/2013, 12:35 am
Re: Other: advice on tandem sea kayak designs *PIC*
Sean Dawe -- 12/3/2013, 9:29 am
Re: Other: advice on tandem sea kayak designs
JohnAbercrombie -- 12/3/2013, 2:42 pm