Back of the postcard. Some of the wording is not readable. It looks like the postcard was sent to a woman, Miss Stewart of California, from Paul Smith.
Howard Hughes (wearing hat) receives congratulations from Mayor Fiorello La Guardia at Floyd Bennett Airport in Brooklyn. The gentleman wearing a polka dot bow tie, standing behind the mayor is Grover Whalen. Mr. Whalen was president of the 1939 New York World's Fair.