Maps and topographic information are basic to military operations, and the changing nature of warfare creates requirements for new types of mapping. During the late 1950s and early 1960s when the American advisory role was becoming established in Vietnam, the old French maps, drawn during French colonial rule in Indochina, were still the best available. But these maps were out of date and failed to meet the accuracy requirements of modern weapons systems.
The U.S. Army Map Service (later the U.S. Army Topographic Command) made cooperative mapping agreements in 1956 with the Republic of Vietnam, on the basis of which joint large-scale mapping programs were undertaken. These operations included cartographic aerial photography as well as the survey of geodetic ground control needed to position large-scale maps, and the collection of information on geographic names and natural and cultural features to be symbolized on the maps. The steady increase in Communist activity in Vietnam was a major obstacle to the completion of the field survey work, and the project had to be abandoned in 1962.
Despite the problems, the Army Map Service and U.S. Army, Pacific, were able to produce in the years 1959 to 1965 1:50,000 and 1:250,000-scale maps of the Republic of Vietnam. This marked the first time that the American military mapping agencies had completed large- and medium-scale mapping of an area in advance of a major commitment of combat forces.
When American participation in the Vietnam War reached a full combat role, requirements for new maps increased accordingly. During the first year of the buildup, 1965-1966, the large-scale coverage of Vietnam, both north and south, was updated on the basis of new aerial photographs taken from 1965 to 1966.
It soon became evident to American operational planners that standard military 1:50,000-scale topographic maps were not adequate for the unusual battle in Vietnam. Tactics developed in previous wars had to be blended with new concepts such as the use of the helicopter as a weapons system, and with more detail and greater reliability in the positioning and identification of features. A new development, the pictomap, represented the first attempt to deal with the problem of feature identification. Drawn at a 1:25,000 scale, the pictomap, which is a photomap with the imagery reproduced in approximate natural color and the major features also annotated in color, made excellent use of aerial photography and constituted an efficient map supplement.
As the American buildup continued through 1968, there was an increase in requirements for the normal topographic support to meet local operational needs. Included were topographic and geodetic surveys for artillery use; cartographic and reproduction work, including map revisions and production of photomaps; and maintenance of operational stocks and maps. To provide these specialized services, Army topographic companies were sent to Vietnam. Army surveyors completed major ground control projects in selected areas for the production of very large-scale coverage. The resulting geodetic control, plus low-level photography procured by the U.S. Army, is being used by various agencies for military purposes and for internal development demands. Work of the Army topographic units included overprinting 1:50,000-scale maps with intelligence information and producing special planning photomosaic, large-scale stereo compilations, and 1:10,000-scale photomaps of selected urban areas.
The excellent state of mapping readiness for operations in Vietnam existed because of long-range topographic planning and the availability of trained topographic troops for prompt deployment. The contributions of these topographic units were a very basic factor in allied military successes. The range of changed tactical operations necessitated maps drawn at larger scales.