The Role of the Gem in Amphibious Support Operations

At a time when shipping must be dispersed to avoid nuclear destruction, the larger ranges required between the supply ship and the shore place a burden on manpower and conventional lighterage that may be beyond their present capability. With the United Kingdom, Russia, and the U.S.A. developing operational overwater GEMs for various purposes, a serious look at the GEM's capability in amphibious support operations is warranted. This paper examines the basic mechanics of ship-to-shore movements of cargo, and attempts to place the GEM in proper perspective with respect to conventional displacement lighterage. The results of a simplified as well as a detailed approach indicate that the GEM, in sizes up to 25 ton payloads, can produce higher degrees of productivity at lower costs than conventional lighters over most of the ranges considered.