Donald Kent "Deke" Slayton (March 1, 1924 – June 13, 1993) was a United States Air Force pilot, aeronautical engineer, and test pilot who was selected as one of the original NASA Mercury Seven astronauts. He went on to become NASA's first Chief of the Astronaut Office and Director of Flight Crew Operations, responsible for NASA crew assignments. He died from a brain tumor on June 13, 1993, aged 69.