United States 1931 Earle Ovington & Frank Hitchcock PMG Signed Airmail Flight Cover

Cover franked with 5c Air Post, tied by Los Angeles machine (Sep 23), two handstruck cachets "Twentieth Anniversary / First Air Mail Flight / P.O. Department / September Twenty Third" and "Earle Ovington - Santa Barbara CAL / First U.S. Air Mail Pilot", signed "Earle Ovington" and Frank Hitchcock / P.M.G. 1909-1913, no backstamps, an attractive piece of aviation history; Ovington piloted the first official airmail flight in the United States in a Blériot XI on September 23, 1911; Hitchcock was Postmaster General at the time.