On his third flight, Hartsfield was spacecraft commander of "Challenger" on STS-61-A, the West German D-1 Spacelab mission which launched from Kennedy Space Center, Florida, on October 30, 1985. His crew included Steven R. Nagel (pilot), James Buchli, Guy Bluford and Bonnie Dunbar (mission specialists), and Reinhard Furrer, Ernst Messerschmid, and Wubbo Ockels (payload specialists). The seven-day mission was the first with eight crew members, and the first Spacelab science mission planned and controlled by a foreign customer. More than 75 scientific experiments were completed in the areas of physiological sciences, materials processing, biology, and navigation. After completing 111 orbits of the Earth, STS-61-A landed at Edwards Air Force Base, California, on November 6, 1985. STS-61-A was the final successful flight of "Challenger", as it was destroyed during the launch of its next mission, STS-51-L.