March 1, 1913–October 12, 2002

BY NICHOLAS ROTT

WILLIAM (“BILL”) SEARS was born in Minneapolis, son of William and Gertrude Sears (née Rees). As described in his recollections, Bill’s youthful interests included music and literature, but by the time he was ready for college his talents in the mathematical and technical sciences determined his choice. He enrolled as a student in the University of Minnesota and earned his bachelor of aeronautical engineering degree in 1934. After that he moved for graduate studies to the California Institute of Technology in Pasadena, where he became a student of Theodore (“Todor”) von Kármán.

Bill Sears was deeply impressed by Kármán’s scientific powers and also by his warm and humane personality. Bill’s thesis on the theory of oscillating airfoils in an ideal flow, submitted in 1938, turned out to be a classic that summarized and enriched substantially all previous efforts in this important field. In 1940 Bill went on to publish a paper, based on the results of the von Kármán-Sears theory, that pioneered the application of operational methods for the solution of problems arising when an impulsive change occurs in the velocity and the shape of an airfoil (1940). Problems that were reduced to a search for the solution of an