With the support of seaplane tenders like Half Moon these missions, called '"Black Cat" strikes, achieved important results in the destruction of Japanese transports.

Steaming out of Morotai on 6 October 1944, Half Moon joined a small convoy en route to Leyte Gulf to assist in the developing operations for the recapture of the Philippine Islands.

Half Moon cautiously slipped out from behind Oabugan Grande Island and was given permission to proceed up the coast of Leyte between, but well to the west of, the two fleets.

She watched the spectacle of Rear Admiral Jesse B. Oldendorf's battleships, cruisers, and destroyers pounding the Japanese ships, and after the battle returned to Hinamangan Bay.

Another fierce air attack, however, soon convinced the commanding officer of Half Moon that San Pedro Bay, further north, offered a more hospitable base for operation.

The convoy, known as "Uncle plus 15", encountered some of the most prolonged and determined air attacks of World War II as the Japanese strove mightily to prevent American reinforcements from reaching Mindoro.

On the afternoon of 31 August 1945 signs of a storm were evident and by 1 September 1945 Half Moon was engulfed in a raging typhoon, with winds up to 120 knots (220 km/h) (222 kilometers per hour) and barometer readings of 27.32 inches (925 millibars).

Barnegat-class ships were very reliable and seaworthy and had good habitability, and the Coast Guard viewed them as ideal for ocean station duty, in which they would perform weather reporting and search and rescue tasks, once they were modified by having a balloon shelter added aft and having oceanographic equipment, an oceanographic winch, and a hydrographic winch installed.

While in Bermuda on a United States Coast Guard Reserve training cruise, Half Moon helped civil authorities in fight a fire aboard the merchant ship Coastal Service at Ordnance Wharf in St. George's, on 14 August 1963.

On 11 January 1967, Half Moon seized four American fishing vessels seven nautical miles (13 kilometers) northwest of Dog Rocks following a shooting incident in which one person was killed and another wounded.

The squadron, which was designated Task Unit 70.8.6, was activated at Pearl Harbor, Hawaii, on 24 April 1967 when its commander, Captain John E. Day, hoisted his flag aboard his flagship, the Coast Guard cutter USCGC Gresham.

The squadron's other Vietnam War duties included fire support for ground forces, resupplying Coast Guard and Navy patrol boats, and search-and-rescue operations.

They departed Pearl Harbor on 26 April 1967 and reported to Commander, United States Seventh Fleet, for Market Time duty on 4 May 1967.

During her tour, Half Moon conducted nine naval gunfire missions along the coast of South Vietnam in support of forces ashore.

Half Moon also served as a home base for 50-foot (15.25 m) U.S. Navy Patrol Craft Fast and participated in search and rescue operations.

[note 1] Half Moon returned from Vietnam to her home port at New York City on 22 January 1968 and resumed her routine Coast Guard operations in the Atlantic.