The first ES-3A was delivered during 1991 and entered front-line service after two years of testing. The U.S. Navy established two squadrons, each equipped with eight ES-3As, stationed in both the Atlantic and Pacific Fleets to provide detachments of typically two aircraft, ten officers, and 55 enlisted aircrew, maintenance and support personnel (which comprised/supported four complete aircrews) to deploying carrier air wings. (source Wikipedia)
Credits:
helijah