 While on station, she acted as an aircraft check point at the point of no return, a relay point for messages from ships and aircraft, as a source of the latest weather information for passing aircraft, as a floating oceanographic laboratory, and as a search-and-rescue ship for downed aircraft and vessels in distress, and she engaged in law enforcement operations.On 24 and 25 August 1951, "Half Moon" assisted the merchant ship "Castello Guadalest" in the North Atlantic at .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.