The US Navy transferred the local islanders to the island of Fedarai for the duration of the hostilities. Arriving next was Service Squadron 10, termed by Admiral Nimitz as his "secret weapon". Its commanding officer, Commodore Worrall R. Carter, devised the mobile service force that made it possible for the Navy to convert Ulithi to the secret distant Pacific base used during the major naval operations undertaken late in the war, including Leyte Gulf and the invasion of Okinawa. Service Squadron 10 converted the lagoon into a serviceable naval station, creating repair facilities and re-supply facilities thousands of miles away from an actual naval port. Pontoon piers of a new design were built at Ulithi, each consisting of the 4-by-12-pontoon sections, filled with sand and gravel, and then sunk. The pontoons were anchored in place by guy ropes to deadmen on shore, and by iron rods driven into the coral. Connecting tie pieces ran across the tops of the pontoons to hold them together into a pier. Despite extremely heavy weather on several occasions these pontoon piers stood up remarkably well. They gave extensive service, with little requirement for repairs. Piers of this type were also installed by the 51st Battalion to be used as aviation-gasoline mooring piers near the main airfield on Falalop.