McDonnell Douglas was an American aerospace manufacturing corporation and defense contractor created in 1967. The company was formed with the merger of McDonnell Aircraft and the Douglas Aircraft Company in 1967. The company maintained its headquarters at Berkley, Missouri. The company was famous for manufacturing the DC-10 airliner and F-15 fighter jets. The company also manufactured helicopters, manned space craft and computer systems. The company was a major defense contractor to the United States armed forces and also had a missile and rocket program. The company ran into financial difficulties in the 1990s and was merged with Boeing to form The Boeing Company in 1997.