The Douglas C-133 Cargomaster is an American large turboprop cargo aircraft built between 1956 and 1961 by the Douglas Aircraft Company for use with the United States Air Force. The C-133 was the USAF's only production turboprop-powered strategic airlifter, entering service shortly after the Lockheed C-130 Hercules, which is designated as a tactical airlifter. It provided airlift services in a wide range of applications, being replaced by the C-5 Galaxy in the early 1970s.