 In the postwar years his interest had turned towards sailing.This resulted (in 1949) in a sentence in a politically motivated process to a prison term under false charges of espionage and "trying to escape to the West" and subsequent long term harassment.In 1953, drawing on his professional background in aerodynamics, Czeslaw Marchaj designed modifications (within class rules) to his Finn class racing boat and subsequently sailed it to a surprising win in a multiday Warsaw-Gdańsk river regatta.