The Department of Defense World Geodetic System 1972

An improved world geodetic system has been developed to satisfy the mapping, charting, and geodetic needs of the Department of Defense. The system, designated WGS 72, represents the culmination of approximately five years of data collection within the Department of Defense and the scientific community. Principal agencies involved in the developmental cycle include the USAF, Defense Mapping Agency, US Naval Weapons Laboratory, and Naval Oceanographic Office. The method of solution for an adjustment of this magnitude is characterized by the formation of a large-scale matrix by combining normal matrices from each of the major data input sets. The scaling and weighting processes for the final matrix are discussed. The resultant ellipsoid parameters, datum shifts and their related accuracies are presented and compared against similar quantities in other recent geocentric systems.