Allan J Fehn

US Patent:

D2607972, Sep 15, 1981

Filed:

Feb 21, 1979

Appl. No.:

6/013263

Inventors:

Gerald R. Calengor - Duluth MN
Allan J. Fehn - Fridley MN

Assignee:

Surf-Jet Corporation - St. Paul MN

International Classification:

D2102

US Classification:

D21228

US Patent:

40917614, May 30, 1978

Filed:

Mar 23, 1977

Appl. No.:

5/780481

Inventors:

Allan J. Fehn - Minneapolis MN

International Classification:

B63B 120

US Classification:

114290

Abstract:

A modified tunnel hull boat in which there are two downwardly extending sponsons defining a tunnel between their inner walls, the boat having a center rib projecting downwardly from the bottom of the boat into the tunnel and having a lower wall which acts as a planing surface. The distance between the inner walls of the sponsons and the outer walls of the center rib decreases from the bow to an area adjacent the midpoint of the boat fore and aft and then increases abruptly after this point so as to create a venturi throat. The reduced pressure adjacent the venturi throat tends to minimize the effect of head or tail winds upon the attitude of the boat. The amount of lift on the rearward portion of the boat is also increased so that the bow does not rise as much at high speeds. The introduction of air into the tunnel is increased by the provision of two flat portions adjacent the bow which are directed upwardly in a forward direction so as to act as scoops to direct air into the tunnel to increase the lifting effect. Curved strakes of relatively short length are provided adjacent the bow to give additional lift to the bow at low speeds.