THE 856th RADIO RESEARCH DETACHMENT
Courtesy of William E. Rowe
werowe@digital.net
The U.S Army's 856th Radio Research Detachment (RRD) was originally constituted on
September 4, 1944, as the 3148th Signal Service Platoon .On September 25, 1944, the platoon was activated for service during World War II on New Caledonia. The platoon was inactivated on January
30, 1946, on le Shima. After service during the Korean War, the detachment was redesignated the 856th Army Security Agency Detachment on April 6, 1966 .
Most of the missions of the U.S. Army Security Agency were highly classified during the war effort. Secret cover designations (radio research designations) were used in lieu of the actual unit designations on unit lists and reports. So the 856th Army Security Agency Detachment
became the 856th Radio Research Detachment (RRD) for service in Vietnam
The 856th RRD was the only direct support unit to the 199th Light Infantry Brigade (LIB) to deploy
with the 280-man advance party to Vietnam in November 1966. The 199th LIB, trained for
counterinsurgency warfare, provided security in the III Corps tactical zone around the Long Binh
complex, the Bien Hoa Air Base and other vital areas in and around the city of Saigon.
The 856th RRD at that time was a 51 - man unit; an infantry officer (usually a captain) was the unit's
commanding officer. The unit commander worked in coordination with the 199th's infantry commanders, offering them a means to check their signal security and improve their communications capabilities.
The overall mission of the 856th RRD was to locate enemy radio transmitters (enemy crystal radio sets) by use of triangulation techniques. The unit used three direction - finding tracking teams located at three different listening post sites, usually forming a triangle with one another .They intercepted, located and pinpointed Viet Cong transmitters. This information was then forwarded to the base camp operations center tor interpretation and analysis. If the information was good, an artillery barrage would be called in on the enemy position.
As the result of the unit's Vietnam service. it received the Valorous Unit Award for combat actions
during the Tel Offensive of 1968, three Meritorious Unit Commendations ,three Vietnamese Cross
of Gallantry - with Palm awards. and two Vietnamese Civil Action Honor Medals (First Class).
Three years after Tet, on March 6, 1971 the 856th RRD was inactivated in Vietnam.
-W.E.R.