Since the early 1980’s there have been several variants of the SH-60 Seahawk. The SH-60B replaced the SH-2 in the anti-submarine warfare (ASW) role. Later the SH-60F and HH-60H succeeded the SH-3 in the ASW and search and rescue missions. An extremely adaptable design, the Seahawk today is the dominant naval helicopter, appearing in a half dozen variants performing virtually all naval rotary wing missions. This flexibility has led to a reorganization of the Navy’s helicopter units, producing two communities of squadrons: “Helicopter Maritime Strike” flying the MH-60R on ASW, maritime surveillance, and attack missions, and “Helicopter Sea Combat” flying the MH-60S on ASW, combat search and rescue, vertical replenishment, and troop transport.