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Re: Odd Question
By:David Bryson
Date: 5/12/1999, 9:55 pm
In Response To: Odd Question (K. Morton)

> I have an odd question. Does anyone know the theoretical speed of a CLC
> chesapeake 17 paddled by moderately fit person in calm conditions with no
> currents. I have 3hrs for a return trip across a channel 5 miles wide to
> visit relatives. I could just run out to the local lake and time myself
> but it seems I always get side tracked or forget to check the time.

The theoretical speed (in knots)of any displacement hull type of boat is about 1.4 * (LWL)^.5 or said in english: 1.4 times the square root of the water line length. So, if the CLC 17 has a 15 ft waterline (i'm guessing) take the square root which equals 3.8 knots (nautical miles per hour) Multiple that by 1.4 adn you get 5.4 knots. This is as fast as you will ever go - unless you can surf down a wave. It is just impossible for the hull to push through the water any faster no matter how much energy you apply.

This is why longer boats are faster boats up until you can no longer apply the necessary energy. An aircraft carrier is one of the fastest displacement boats in world for this reason. 1.4*(900ft)^.5 = over 40 knots.

However, you will never maintain this type of speed in reality. You could maintain 1.0*(LWL)^.5 or about 3.8 knots for a reasonably short period of time.

But my guess is that you would be lucky to keep up 0.8*(LWL)^.5 or three knots for several hours. Waves, wind, tracking, all bring this number down further.

Messages In This Thread

Odd Question
K. Morton -- 5/12/1999, 6:12 pm
Re: tangental answers
lee -- 5/14/1999, 3:06 pm
Re: Odd Answer
Mike Scarborough -- 5/13/1999, 8:24 am
Re: Odd Question
David Bryson -- 5/12/1999, 9:55 pm
Re: Hull Speed
Nick Schade - Guillemot Kayaks -- 5/14/1999, 9:15 am
Re: Hull Speed
David Bryson -- 5/14/1999, 7:17 pm
Re: Odd Question
Jim -- 5/13/1999, 12:53 pm
Narrow hulls
Brian T. Cunningham -- 5/13/1999, 1:20 pm
Re: Odd Question
Robert Woodard -- 5/12/1999, 6:59 pm
Re: Odd Question
J . P. Scheib -- 5/14/1999, 3:39 am