Hobie Cat makes a pedal system for their kayaks that is like a set of wings
flapping under the boat. I've never tried it myself but it looks like an
interesting idea.

http://www.hobiecat.com/kayaking/index.html

- Scott

"Bob La Londe" wrote in message
...
I have wondered about the efficiency of peddle power.

Glen-L has a nice design for a peddle powered boat, and there are numerous
peddle powere ABS plastic boats available for sale at moderate prices both
on-line and in the local big box stores.

They all have one thing in common. They use a paddle wheel for
propulsion.
I can see the obvious simplicity in design. A chain from the pedals to
the
drive axle and its ready to go. In almost all other craft though a
propeller desing seems to be more efficient.

From big ships to small pleasure craft the propellor seems to be the rule.
For a small peddle powered craft would a prop design make the best use of
the available power as well? How in the world woudl you go abotu figuring
out the optimum size and pitch prop for an application like that?