The USS Eldridge (DE-173) is a Cannon-class destroyer escort that served in the United States Navy. It was laid down by the Federal Shipbuilding and Dry Dock Company in Newark, New Jersey, her hull was launched on 25 July 1943, and commissioned on 27 August 1943.
From then on the Eldridge participated in numerous operations until after World War II where it was put commission in reserve on June 17, 1946. On January 15, 1951, it was transferred under the Mutual Defense Assistance Act to the Greek Navy where it served as HS Leon (D-54). Leon and was used mainly for patrols in the Easter Aegean Sea and for cadet officer training.
The Leon was decommissioned on November 15, 1992 and was later sold for scrap to the Piraeus-based V&J Scrapmetal Trading Ltd in November 1999.
The "Philadelphia Experiment" was an alleged naval military experiment at the Philadelphia Naval Shipyard in Philadelphia, Pennsylvania, sometime around 28 October 1943 in which the USS Eldridge was to be rendered invisible (i.e. by a cloaking device) to human observers for a brief period. It is also referred to as Project Rainbow.
As a result of the experiment, the ship as well as two soldiers from the future, George Gordon Haggard Jr. and Arkady Kirilenko, were temporarily transported to an alternate reality where a war reminiscent of World War II was being waged between the Royal and National Armies.