133 years ago today, April 6, 1892 (March 10, 1892, lunar calendar), American aircraft designer Douglas was born. On April 6, 1892, Douglas, an American aircraft designer and founder of the Douglas Aircraft Company, was born. Douglas assisted J.C. Hensack in building the first wind tunnel at the Massachusetts Institute of Technology in 1914 and 1915. Douglas Aircraft Company was founded in 1920. Two of the early Douglas biplanes flew around the world from April to September 1924. After manufacturing the DC-1 prototype and the DC-2 production prototype, in 1935, the DC-3 "military code Dakota C-47" transport aircraft with greater power and better performance were produced. Other commercial aircraft include the four-engine DC-4 model (the military model is called C-54 in the Air Force and R5D-1 in the Navy), and the DC-6 and DC-7 models are more famous. During World War II, Douglas built A-20, A-26 light bombers and SBD dive bombers. Aircraft produced after the war included DC-8, DC-9 and DC-10 jet transport aircraft, as well as A-4 assault bombers. In 1957 he resigned as chairman of the Douglas Aircraft Company. He died on February 1, 1981.