THUNDERBIRD. 

 Photo by 

 Kenneth G. Ollar, 

 courtesy Stefan Thordason. 



pect that it was to be made of plywood, though we are told fiber glass may 

 now be used on top of plywood. 



The enthusiasts who have written about the boat seem to think that 

 Seaborn's Thunderbird, as the 26-foot class of sloops came to be called, 

 comes very close to achieving what Seaborn first called impossible. During 

 the Tacoma Yacht Club's 1958-59 winter racing season, under the capable 

 Douglas Sherwood, the first Thunderbird won several races, including those 

 in light, medium, and gusty winds. In one race, according to Frank C. 

 Beesom,* "she was clocked M better than 10 knots under reefed main and 

 spinnaker on a consistent semi-plane." Seaborn credits the good sailing per- 

 formance of the Thunderbird to three things: ( 1 ) the hydrofoil keel ("in the 

 shape of a symmetrical hydrofoil in vertical section, producing a highly 

 favorable ratio of lift over drag . . . blunt on the leading edge and feathered 

 to a trailing edge" ) , ( 2 ) the hard chines, and ( 3 ) the lightweight hull. 



* "Are You Ready for Your First Cruising Boat," by Frank Carter Beesom, Popular Boating, 

 July 1961. 



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THE SAILBOAT CLASSES OF NORTH AMERICA 



