HS-4 was the first anti-submarine warfare (ASW) helicopter squadron of the U.S. Navy to deploy aboard an aircraft carrier, the escort carrier Rendova (CVE-114). In 1954/55 HS-4 was deployed on the Essex-class aircraft carrier Princeton (CV-37). Afterwards the squadron converted to the Sikorsky HSS-1 Seabat helicopter and first deployed aboard the Boxer (CV-21) in 1956. This was followed by a cruise aboard the Princeton again in 1958. HS-4 could be identified at that time by the tail code "TA" (1955-1960). In 1961, it became the first ASW squadron in Commander Naval Air Forces Pacific (COMNAVAIRPAC) to achieve around-the-clock ASW capability, earning HS-4 the title "Black Knights".
From 1960 to 1968 HS-4 made six deployments aboard the Yorktown (CV-10) to the Western Pacific as part of Carrier Anti-Submarine Air Group 55 (CVSG-55) (tail code "NU"). In 1964 the squadron converted to the Sikorsky SH-3A Sea King. HS-4 was initiated into combat during its 1966 cruise to Southeast Asia. While operating in the Gulf of Tonkin, HS-4 pilots and aircrew rescued 24 downed airmen under hostile fire, a record for an ASW squadron in a single deployment. In 1968 HS-4 aboard Yorktown was part of the Task Force sent to the Sea of Japan at the beginning of the USS Pueblo incident.