KATZ, RECONNAISSANCE PIONEER.

Byline: Eric Pace The New York Times

Amrom H. Katz, one of the fathers of space reconnaissance - the use of space satellites to collect intelligence by photography and other means - died Monday at St. John's Hospital in Santa Monica. He was 81 and lived in Los Angeles.

The cause was complications from Parkinson's disease, said his son, Michael, of Santa Monica.

Katz was also an authority on the detection of weapons systems and other military capabilities of Cold War opponents.

From 1941 to 1954, he played a central role in improving photographic reconnaissance equipment and systems at Wright Field, now Wright-Patterson Air Force Base, near Dayton, Ohio, becoming the chief civilian physicist of an aerial reconnaissance laboratory there.

In 1954, Katz joined the staff of the Rand Corp., a research organization based in Santa Monica, and specialized in reconnaissance systems for airplanes and spacecraft; he was a senior scientist at Rand until 1970. Later, he worked for Rand as a consultant.

He went on to become an assistant director of the U.S. Arms Control and Disarmament Agency, and was its ranking expert on determining how fully arms control treaties were carried out. He served with the agency from 1973 until he resigned in 1976.

John Pike, an authority on space policy who is the director of the space policy project at the Federation of American Scientists, an organization that is based in Washington, said Thursday that Katz's ``early studies made possible the reconnaissance satellites that were a mainstay of intelligence collection and treaty verification during the Cold War.''

Most of those studies were carried out at Rand in the 1950s. Pike said they were critically important because they ``identified how one would do photographic intelligence from space.''

William Harris, a Rand consultant who is an expert on arms control treaties, said of Katz: ``In the 1950s and early 1960s, he was really the world's pre-eminent expert on the use of photographic systems in piercing Cold War secrecy. His expertise helped others in the West to construct reconnaissance systems that enabled successive Western political leaders to manage Cold War crises more effectively in the nuclear age.''

Katz was born in Chicago, grew up in Milwaukee, received a bachelor's degree in 1939 from the University of Wisconsin, and did graduate work at the Massachusetts Institute of Technology.

In 1946, he supervised the Army Air Forces' photography of the atomic bomb tests at Bikini atoll in the Marshall Islands in the western Pacific.

During the Korean War, in preparation for the successful amphibious landing of American troops at Inchon, South Korea, Katz devised a plan to measure the height of a sea wall at the harbor without alerting enemy forces of the impending attack. He did it by having airplanes take photographs of Inchon at carefully timed intervals, and then using trigonometry to calculate the height of the wall and to show that it would not be a major obstacle to the Marine Corps landing on Sept. 15, 1950.

In 1957, Katz and a Rand teammate, Merton Davies, advocated the use of cameras and film-recovery systems in space reconnaissance to gather intelligence about the Soviet Union from places where intelligence-gathering had not been possible before. Rand's recommendations were promptly accepted by the Air Force.

Harris said that Katz ``was among the earliest champions of the use of reconnaissance by spacecraft to take the place of inspectors on the ground as the main means of monitoring the implementation of proposed arms control treaties.''

Katz was sometimes a critic of American reconnaissance techniques in the Cold War, too. Harris said that in 1964, Katz ``did a study for Walt Rostow, then the special assistant to President Lyndon Johnson for national security,'' in which Katz ``assessed and summarized Soviet knowledge of U.S. reconnaissance, and he argued that much of what we learned, the Russians wanted us to know; and much of what we didn't learn, they wanted us not to know.''

Over the years, Katz was also quick to discern possible civilian applications of reconnaissance technology - notably in conserving water, forests, and other natural resources and in helping victims of natural disasters.

Besides his son, Katz is survived by his wife of 56 years, the former Louise Klibanow; two daughters, Barbara Katz of Santa Monica and Deborah Kovar of Canoga Park; two brothers, Yale, of Bellingham, Wash., and Matty, of Milwaukee; and six grandchildren.