|Occupying force:|| French Frigate Shoals is an atoll with a diameter of 18-miles (29-kilometers). Located 558-miles (898-kilometers) west-northwest of Ford island, Pearl Harbor, it is a 20-mile (32-kilometer) long crescent-shaped reef, 13 sand islets and the 122-foot (37-meter) high La Perouse Pinnacle, the only remnant of its volcanic origins. The total land area of the islets is 61.5 acres (24.9 hectares) and total coral reef area of the shoals is more than 232,000 acres (93.9 kilohectares).
The Navy began using this atoll in the 1930s in training exercises and Consolidated PBY Catalinas operated from it even though facilities were minimal.
In order to prevent Japanese submarines from using the area as a refueling point for flying boat raids on Hawaii, the U.S. Navy sent light minelayers to mine French Frigate Shoals on 4 April 1942.
The Navy decided to build a minor naval air facility to support the staging of aircraft flying between Hawaii and Midway Islands and to serve as an emergency fueling stop and as a link in the radar chain centered in the Hawaiian Islands. Construction was started during July 1942 by the Seabees. The major development centered about Tern Island in the northwest corner of the reef. A ship channel, 200-feet (61-meters) wide, was dredged through the barrier reef, and a seaplane runway, 8,000-by-1,000-feet (2 438-by-305-meters), was cleared in adjacent waters. This runway was also provided with an a 4,000-square-foot (372-square-meter) mooring area. By use of coral dredged from the channel and seaplane runway, Tern Island was increased in area to 26 acres (10.5 hectares) to permit the construction of a 3,100-by-250-foot (945-by-76-meter) coral-surfaced landing field. A parking area to accommodate 24 single-engine aircraft was also provided.
The Navy commissioned Naval Auxiliary Air Facility French Frigate Shoals on 17 March 1943.|