MIL-STD-2401

Abstract

This standard specifies the requirements for use of World Geodetic System 1984 (WGS 84), the defining and derived parameters for WGS 84, and methods for transforming between WGS 84 and other geodetic systems. <br>This standard applies to all DoD systems and products which require use of a World Geodetic System. A world geodetic system is a consistent global coordinate system which allows an unambiguous representation of positional information. Navigation solutions from the NAVSTAR Global Positioning System (GPS) and the Navy Navigation Satellite System (NNSS) are referred to this system. A WGS 84 ellipsoid provides a reference surface upon which coordinates are calculated and is particularly applicable to inertial systems. A WGS 84 Earth Gravitational Model (EGM) provides necessary force models for accurate global operation of strategic weapons, navigation, and satellite systems. Many MC&G products produced by other agencies and governments (and DMA products not yet placed on WGS 84) are not referred to the WGS 84. Parameters to transform these products to WGS 84 are part of this standard. <br>This standard is UNCLASSIFIED. The procedures and processes presented in this standard may be used for classified processing with the addition of appropriate security provisions. <b><u>Intended Use:</u></b> To provide a reference for development of systems which must operate in the DoD World Geodetic System 1984. Geodetic heights (h) are purely geometric and independent of the effects of variation in the earth gravity. This height is directly obtained through satellite positioning, but is not generally available in local datums. It is not possible to transform between vertical datums as no information exists on the relationship of the various MSL determinations. In practical applications, the difference between orthometric height and elevation is ignored. <br>