Issued on March 19, 1976, the 13-cent Commercial Aviation stamp celebrates the 50th anniversary of a pivotal moment in American aviation history: the inauguration of contract airmail flights. The Air Mail Act of 1925, also known as the Kelly Act, authorized the Postmaster General to contract with private airlines to carry mail. This legislation was the catalyst that transformed airmail from a government-operated service into a commercially viable industry, which in turn gave birth to passenger air travel. The first of these contract flights, commemorated by this stamp, occurred on February 15, 1926, when a Ford Air Transport plane flew from Dearborn, Michigan, to Cleveland, Ohio. The stamp's design features two important aircraft from this pioneering period: a Ford Pullman monoplane, used on the inaugural flight, and the iconic Ford Trimotor, known as the "Tin Goose," which became one of the first successful passenger airliners. This stamp pays tribute to the entrepreneurial spirit that built the American airline industry, an industry that was quite literally carried on the wings of the U.S. Mail.