The US company McDonnell Aircraft received a request in 1942 for a jet fighter which could be operated from U.S. Navy aircraft carriers. The eventual result was the FH-1 Phantom, a twin-engined craft that was only moderately faster than the best propeller fighters of the time. The Navy ordered 100 planes (only 60 were actually built), and the first units were delivered in 1947. They were used to equip one Navy and two United States Marine Corps squadrons. They were the first carrier-based pure jet fighters acquired and put into operational service by the Navy.