Division of the Air Force Special Weapons Center. ("Special weapons" is a euphemism for nuclear and thermonuclear bombs.) Allen specialized in the military effects of high altitude nuclear explosions and participated in several nuclear weapons test series. He was scientific director of a major experiment that utilized a large series of high-altitude rockets to measure the characteristics of electrons trapped in the geomagnetic field after an exoatmospheric nuclear burst. Allen was assigned in December 1961 to the Office of the Secretary of Defense, Space Technology Office, in the Directorate of Research and Engineering, Washington, D.C. From June 1965 to February 1973, he was assigned to the Office of the Secretary of the Air Force, initially in Los Angeles, California, as the deputy director for advanced plans in the Directorate of Special Projects. Allen next moved to The Pentagon in June 1968 as the deputy director of space systems, and in June 1969, he became the director. He returned to Los Angeles in September 1970 as the assistant to the director of special projects and in April 1971 became the director of special projects, with additional duty as the deputy commander for satellite programs of the Space and Missile Systems Organization. After serving briefly as the chief of staff for the Air Force Systems Command at Andrews Air Force Base, Maryland, Allen was appointed in March 1973 as a deputy to the Director of Central Intelligence for the Intelligence Community in Washington, D.C. In August 1973, Allen became the director of the National Security Agency (NSA) and the chief of the Central Security Service at Fort George G. Meade, Maryland. Allen's tenure as the NSA director was noteworthy in that he became the first director to ever testify publicly before Congress. In August 1977, he was named commander of Air Force Systems Command. Allen served as the Vice Chief of Staff of the United States Air Force from April 1978 until he became the Chief of Staff of the Air Force in July 1978. His nomination was unusual in that he had never served in an overseas or combat assignment, and most of his positions were in specialized technical activities, rather than in the usual command structure of the Air Force. Also, he was the last chief of staff with a bomber background; all subsequent chiefs of staff except General Norton Schwartz have been fighter pilots, and this trend is reflected