At Cadillac, 1948 was the "Year of the Tailfin". The 1948 Cadillac Series 61 four door sedan was an American Automobile with one of the first tailfins.
After World War ll Cadillac designers Earl Mitchell and others took a look at the Lockheed P-38 "Lightning" pursuit fighter. Designers and engineers played with ideas for a postwar styling inspired by the planes design features.
Features that include pontoon front fenders, pointy front, cockpit like curved windshield and tailfins. It was the fin that had the most lasting impact.