MGM-5 Corporal - Design and Development

Design and Development

The Corporal was first developed in White Sands Missile Range, New Mexico drawing on the technical experience and expertise that the Americans acquired from the German V-2 rocket program after the Second World War. After being sold to Britain in 1954, it became the first U.S. guided missile destined for service in a foreign country to be used by a foreign power. Subsequent test-firing by British and German Corporal regiments/battalions took place in the Scottish island of South Uist, where a special Royal Artillery "Guided Weapons Range" was built at West Gerinish in 1957-58. It was fired towards the tracking station built on the lonely island of St Kilda

For what was the front line of nuclear defense, the Corporal missile was notoriously unreliable and inaccurate.* It used a liquid-fueled rocket burning red fuming nitric acid and hydrazine; this required elaborate and time-consuming preparation immediately before launch, making its tactical responsiveness questionable. For guidance, it employed commands sent through a reworked World War II-era radar system. Until 1955, its in-flight accuracy was less than 50 percent, with only modest improvements thereafter. The first year of British test firings in 1959 yielded a success rate of only 46 percent, a dismal record which raised questions among military planners of its operational effectiveness in Germany.

• While this may have been true of the first deployed Corporal missiles, the later generation Corporal Type IIB were surprisingly accurate for their time.

Guidance consisted of a complex system of internal and ground guidance. During the initial launch phase, inertial guidance (internal accelerometers) kept the missile in a vertical position and pre-set guidance steered it during its launch. The ground guidance system was a modified SCR584 pulse tracking radar which measured the missile's azimuth and elevation, as well as its slant range. This information was sent to an analog computer which calculated the trajectory and any necessary correction to hit the target. A Doppler radar was used to accurately measure the velocity and this information was also used in the trajectory calculation. The Doppler radar was also used to send the final range correction and warhead arming command after the missile re-entered the atmosphere. Transponder beacons were used in the missile to provide a return signal.

Corporal Missile Battalions in Europe were highly mobile, considering the large number of support vehicles and personnel required to support the transportation, checkout, and launch of this liquid-fueled nuclear-tipped (or conventional HE) missile. In Germany, frequent unannounced "Alerts" were performed—necessitating assembling all personnel and moving vehicles and missiles to a pre-assigned assembly point. From there the battalion would move to a launch site—usually somewhere in a remote forest—set up the missile on its launcher and go through a detailed checkout of the various systems. This was not a trivial operation as these electronic systems were all vacuum tubes. A mock firing would be performed and the entire battalion would be gone as soon as possible in order to not be a target of counter-battery fire. The deployment in the field during an Alert was amazingly swift due to the highly trained crews.

One outstanding Corporal Missile unit, the 1st Missile Battalion of the 38th Artillery (1/38th) was stationed in Babenhausen Kaserne. Its fire mission was to protect the Fulda Gap from an armored invasion by the Soviet Union and Warsaw Pact nations. Eventually the Corporal IIB was overtaken by advances in technology and in 1963 they began to be deactivated—replaced by the Sergeant missile system.