Foilcat- Dave Carlson

Hydrofoil!

The Foilcat "Kangalope", a Hobie 18 fitted with surface-piercing foils, has been tested extensively in Florida since late 1997. It has been sailed on the foils 50 different days, in North Florida, off the beach at Daytona, at Ft. Lauderdale and Miami, even at Rick's Place in the Keys. The Foilcat "Jackalope", built on a Hobie 16, was first in the water at the Miami Boatshow in February 1999, and has been out foiling ever since. This foiling was great fun, as can be seen from the photos at Lake Santa Fe in North Florida, but it was also directed at improvement of speed and behavior of the rig.

We are currently working on modifying the major aluminum lifting foil shape, to replace the Clark-Y flat bottomed lifting foil currently in use. We anticipate that this may lead to a commercial product with better behavior.

What is sailing a Foilcat like?-- Getting a thoroughbred racehorse galloping at its top speed- a tall horse way off the ground going way too fast! Normal beach cats are fast too- but now they feel more like small, short-legged ponies! These Foilcats need 11 knots to climb up out of the water and fly BOTH hulls. They need wind of sustained 13 knots to foil continuously. Technically, the realistic goal is something like 1.5 times windspeed for this and all other foiling boats. In a breeze, it surely felt like 28+ knots (31+ miles per hour) to me, based on many years of water skiing!

Cheetalope is an A-Class wooden Catnip design built by Cal Fuller in 1971. She weighs 200 pounds and sails beautifully off the foils. I have added a surface-piercing foil set that rotates easily down into foiling position, and is fastened to aluminum tubing that inserts into the crossbar. Little modification to the boat in needed. I'm using the same modified stock fiberglass Hobie rudders with the single fin as on Kangalope and Jackalope. The much lighter weight allows the rig to come out of the water and have sustained flights lasting several minutes. The aluminum surface-piercing foil assembly weighs fifteen pounds each side. I've sucessfully foiled with this rig about fifty times.

One big advantage of surface-piercing foils is that when foiling, the boat does not crash and then pitchpole like T-foilers sometimes do. With loss of wind at speed, these surface-piercing foilers just settle back into the water at about ten MPH and then immediately pick up to full speed when the wind returns.

 

And now for some pictures.. Click to enlarge..

photos taken during recent development/testing of the hydrofoils

Side view of small foil set
Front view of small foil set
(Pictures added 9-22-02)

(Pictures added 5/30/2001)

 

Visit the Hobie Fleet 153 Homepage, featuring some more photos of the foilboats.

look here for more info on foiling in general

 

Footnote: Catcobbler

"Catcobbler" is the business name I used in the 1980's when making the first commercial Quick Fit Rudder Cam Pins for Hobie 16s. The name at least still lives: Perhaps it will live again soon as a source for Foilcat Kits!

Dave Carlson
731 NW 91st St
Gainesville, FL 32607, USA

dacarls@gmail.com