Ashley Chadbourne McKinley (June 23, 1896 – February 11, 1970) was an accomplished American aerial photographer and colonel in the U.S. Army Air Corps who helped pioneer aviation at subzero temperatures. He accompanied Richard E. Byrd as an aerial photographer on his expedition to the South Pole. Early career McKinley joined Battery A of the Missouri National Guard on June 21, 1916, and served on the Mexican Border until December 21 of the same year. Following the United States' entry into the First World War, he enlisted in the United States Army Signal Corps on August 7, 1917, and became a dirigible pilot. He was commissioned as a 1st lieutenant in the Officer's Reserve Corps on December 7, 1917, to date from November 27. He was placed on active duty on December 16, 1917. During World War I, he commanded a balloon observation company. He later taught aerial photography and surveying. He was promoted to the rank of captain on November 20, 1918, shortly after the armistice. Interwar period Due to the post war draw down, McKinley's appointment as captain was vacated and he was made a 2nd lieutenant in the Army Air Service on September 21, 1920 (to rank from July 1, 1920). He was promoted to 1st lieutenant on April 12, 1921. On April 3, 1926, McKinley resigned from the Army to begin an aerial surveying and photography service. In 1928–1929, he was a photographer for the Byrd Antarctic Expedition. He was one of four men (along with Richard Byrd, Bernt Balchen and Harold June) aboard the first aircraft to fly over the South Pole on November 29, 1929. He was decorated with the Distinguished Flying Cross by Secretary of War Patrick J. Hurley on July 9, 1930. World War II In 1941, as the United States prepared to enter the Second World War, McKinley rejoined the Army Air Corps as a major. He was in charge of the cold-weather operations of the Army Air Force at Ladd Field in Fairbanks, Alaska. McKinley was the first person to suggest that U.S. aircraft be constructed to operate in subzero temperatures and that the Air Force should build a facility to test aircraft in subzero temperatures. He was transferred to Eglin Field for the construction of the facility. He had risen to the rank of colonel by the war's end in 1945. Post war McKinley transferred from the Army to