At the time the British Army was going to buy the American MIM-46 Mauler for air-defense. Mauler ran into problems in 1963, so the Ministry of Defence started giving money to Sightline. Sightline was supposed to be a backup in case Mauler failed. This eventually happened, and Sightline was eventually developed as "Rapier". The missile was 1966 for testing. Full versions of Rapier were tested in 1968. A contract was given in 1969 for the missile to begin being made. Rapier began being used in 1971 with the British Army, and 1974 with the Royal Air Force Regiment.