Thor Missiles

In 1954, the USAF issued a Request for Proposals for an Intermediate Range Ballistic Missile capable of carrying a thermonuclear bomb 1,500 miles -- the distance from England to Moscow. The Douglas Aircraft Company came up with a design that used the warhead and guidance system already in development for the Atlas missile. For propulsion it used the engine from the Navaho cruise missile, which at the time was "the only one available." Since the missile would be deployed from England, security during transporting was a major design consideration, so the Douglas design was only sixty-five feet long, permitting it to fit inside a Douglas C-124 Globemaster II for tightly controlled movement to and from launch sites. In August 1956, only seven months after Douglas received the contract, the first missile was ready to fly. It was named the Thor.

By September 1957, Thor had successfully flown to a range of 1,250 miles while heavily weighted down by instrumentation. The first operational Thors were deployed in England by the end of 1958 and remained there until August 1963.

The Thor evolved through several 3-stage and 4-stage configuration, for use in many roles, including space exploration, military testing, scientific exploration, and strategic reconnaissance.

Its first application in the area of space exploration was in August 1958 in a failed attempt to launch the first Pioneer lunar probe. During 1962, several Thors were also used for high-altitude tests of nuclear weapons, and were launched from Johnston Island in the south Pacific to detonate above the atmosphere.