Gilbert Islands
by Jack McKillop

Physical Description & History

     The Gilbert Islands are a chain of 16 atolls and coral islands in the central Pacific Ocean about 2,391-miles (3,848-kilometers) southwest of Pearl Harbor, Territory of Hawaii and 2,380-miles (3,832-kilometers) north-northeast of Brisbane, Queensland, Australia. The islands extend north to south from 3°24'N, 173°40'W to 2°40'S, 176°51'W. The land area of these islands is 108 square-miles (281 square-kilometers) while the lagoon area is 721 square-miles (1,867 square-kilometers).
     The first European to “discover” the Gilberts was a Spanish explorer in 1606; he saw Makin Atoll. In 1788, a British ship cruised throughout the islands but did not land. During the 19th Century, many ships, including two U.S. Navy vessels, sailed through these islands while sailing in the central Pacific.
     A British protectorate was first proclaimed over the Gilberts by the United Kingdom on 27 May 1892 and in 1915, the Gilbert Islands were proclaimed a colony of the British Empire. On 9 December 1941, the Japanese landed on three atolls and then conducted an air raid on Tarawa Atoll, the administrative center of the islands. They again bombed Tarawa on 24 December and Japanese forces landed the same day. During the summer the Japanese garrisons were reduced because it was felt that there was no danger from Allied forces. That changed on 17-18 August 1942 when U.S. Marine Corps (USMC) raiders landed on Makin and Butariari Islands in Makin Atoll, the northernmost island in the Gilbert Islands. The Japanese then reinforced the garrisons and built defensive fortifications on Makin and Tarawa Atolls.
     During World War II, the U.S. Navy built two air bases in the Gilbert Islands.    
     In 1971, the Gilbert Islands were granted self-rule by the United Kingdom and complete independence in 1979 under the new name of Kiribati. Kiribati encompasses three island groups, the Gilbert, Line and Phoenix Islands. The US relinquished all claims to the sparsely inhabited Phoenix and Line Island groups in a 1979 treaty of friendship with Kiribati.

Abemama Atoll, Naval Air Base

     Abemama Atoll (0°24'N, 173°50'E) is located about 83-miles (134-kilometers) southeast of Tarawa Atoll. The correct name is Abemama but it was known as Apamama to the U.S. military in World War II.
     The atoll is oval shaped, about 15-miles (24-kilometers) long northwest to southeast and 6-miles (9.7-kilometers) wide. Total land area is 11 square-miles (28 square-kilometers). The lagoon area is 51 square-miles (132 square-kilometers). The atoll consists of 11 islands and islets; the largest island is hook-shaped Abemama Island which is about 7-miles (11-kilometers) long and 1,000 to 2,000 yards (914 to 1,829 meters) wide with a total land area of 6.2 square-miles (16 square-kilometers).
     The Japanese first occupied Abemama Island on 31 August 1942 but they departed four days later. In 1943, a small detachment of Japanese troops had reoccupied the island but by mid-October, the atoll appeared to be unoccupied.
     USAAF B-24 Liberators flew their first reconnaissance mission over the atoll on 26 January 1943. This was followed by five bombing missions between 26 May and 19 September 1943.
     In November 1943, a Marine reconnaissance company was tasked with determining the number of Japanese on the island. The company landed by rubber boat  at the southeast corner of the atoll at 0445 hours local on 21 November from the submarine USS Nautilus (SS-168). The Marines found 23 Japanese troops and they were either killed or committed suicide. On 25 November, a Marine battalion landed and occupied the atoll.
     Construction of an airfield began almost immediately on Abemama Island. A 4,000- by 150-foot (1,219- by 46-meter) fighter strip, O'Hare Field (0°29' 27N, 173°49' 44E), was built on the northwest hooked end of the island. The field was ready by 10 December, and the first plane landed three days later. The runway was extended to 6,000-feet (1,829 meters) for bomber operations by 21 December. By March 1944, installations at O'Hare Field consisted of a 7,700- by 200-foot (2,237- by 61-meter) coral-surfaced USAAF bomber strip, with an additional 1,950-foot (594-meter) sand strip; 21,000-feet (6,401 meters) of taxiways, with 100 coral-surfaced hardstands 125- by 150-feet (38- by 46-meters); and Quonset huts for ready rooms and repair ships. Additional construction went into building 19-miles (31-kilometers) of coral-surfaced roads, a 12,000 barrel tank farm, a 5,000-foot (1,524-meter) submarine pipeline and an unloading pier for unloading and making minor repairs to landing ship, tanks (LSTs) and smaller craft. The final aviation facilities were greater than planned but the location proved of strategic importance for bombing missions to adjacent Japanese bases in the Gilbert and Marshall Islands.
     While the airfield was being constructed, Japanese aircraft bombed the island four times with the loss of one B-24 and damage to the hardstands and taxiways.
     The U.S. Army Air Forces’ (USAAF) name for this base was Abemama Airfield. From December 1943 to April 1944, two squadrons of B-25 Mitchells were based here followed by two squadrons of B-24s from January to March 1944 when they tranferred to the Marshall Islands. After the bombers left, a troop carrier squadron was based here from 27 March to 4 August when it transferred to the Mariana Islands.
     U.S. Navy PB4Y-1 Liberators also operated from this base beginning in December 1943.
     Naval Air Base Abemama was commissioned on 15 April 1944 but as the war moved west, the need for this airfield decreased and the base was decommissioned on 16 October 1944.
     Kwajalein Atoll in the Marshall Islands had been captured by early February 1944 and by May, combat aviation units had left Abemama and it became a rear area.
     In 2011, O’Hare Field is named Abemama Atoll Airport.

Tarawa Atoll, Naval Air Bases

     Twelve square-mile (32 square kilometer) Tarawa Atoll (1°26'N, 173°00'E) is a triangular-shaped atoll composed of a series of islands in a reef covering 22-miles (35-kilometers) in length. The 133 square-mile (344 square-kilometer) enclosed lagoon, about 17-miles (27-kilometers) long and tapering from 8-miles (13-kilometers) to less than a-mile (1.6-kilometers) in width, is open to the west, though partially barred by a section of the submerged reef. The 18-mile (29-kilometers) long northeast side consists of 42 islands and islets oriented northwest to southeast and the 12-mile (19-kilometers) long base has five islands running west to east. The western side of the atoll is 13-miles (20-kilometers) long and is barred by a coral reef. The U.S. Navy build naval air bases on two of the islands, Betio and Bonriki.
     Betio Island is the largest island in the atoll and was the administrative center of the British Gilbert Islands. The island is 2.2-miles (3.5-kilometers) long, 800-yards (732-meters) wide at the west end which tapers to a point at the east end. Total land area is 291 acres (118 hectares).
     After landing on Makin Island to the north on 10 December 1941, a detachment of Japanese troops landed on Betio but after rounding up a few Europeans, they left. They returned two weeks later on 24 December and captured seven coastwatchers. On 3 September 1942, the Japanese returned again and searched all of the islands and islets and captured 17 coastwatchers and five Europeans. On 15 September 1942, Japanese Special Naval Landing Force troops arrived with construction troops to build one of the most strongly defended islands of its size in the world. Over 500 pillboxes, bunkers and shelters were built of coconut logs, steel and concrete. A 4,400- by 150-foot (1,341- by 46-meter) coral runway airstrip was also built running east to west on Betio.
     USAAF B-24 Liberators flew their first reconnaissance mission over Tarawa on 26 January 1943. These missions continued until a bombing mission was flown on 23 April against gas storage and barrack areas. At least 12 other bombing missions were flown, the majority in November.
     In 17 September 1943, a three-carrier task force attacked Tarawa, Makin, and Abemama Atolls followed by aircraft from six heavy and five light aircraft carriers on 18 and 19 November.
     By November 1943, the Japanese garrison consisted of almost 4,700 men. The U.S. Marine Corps’ (USMC) 2d Division landed on Betio on 20 November 1943 and after a brutal four day battle, the island was declared “secured.”
     The early completion of an operational airstrip using the Japanese airfield was the primary objective. By 18 December, a fighter airstrip running east to west and named Hawkins Field (1°21' 22N, 172°55' 48E) was usable; two days later the first unit of the garrison air force, U.S. Navy Fighting Squadron One (VF-1), took off from two escort carriers with 44 F6F-3 Hellcats and landed on the airfield. The fighter strip was 4,000-feet by 150-feet (1 341 by 46 meter) and had 18 hardstands. PBY-5 Catalinas and PV-1 Venturas soon followed.  
     The length of the Hawkins Field runway was marginal for bombers so a second airfield was built on Bonriki Island, the largest island in the atoll, to accommodate USAAF B-24s and B-25 Mitchells. The Navy named this airfield Mullinix Field (1°22'54"N, 173°08'49"E) but the USAAF called it Bairiki Airfield. The completed bomber strip was 7,050-feet (2,148-meters) long with a surfaced width of 200-feet (61-meters), and had 27 hardstands.
     In December 1943, two squadrons of B-25s arrived on Hawkins Field followed in January by a B-24 squadron. These units moved to Bairiki Airfield in January 1944.  Hawkins was then used by Navy PBM Mariners, PBY Catalinas, PB2Y Coronados and PV1 Venturas.
     In December 1943 and January1944, Japanese bombers bombed Tarawa 14 times. The number of aircraft involved in these raids varied from one to 15, but normally not more than five or six appeared.
     Besides the two landing fields, the Navy Seabees built all the necessary housing and living facilities for 1,300 men of the unit which operated the field, a 100-bed Quonset-type hospital, ammunition and bomb storage, a control tower, an aviation-gasoline tank farm of 500,000 US gallon (416,337 Imperial gallon or 1.893 billion liter) capacity and ready tank storage of 20,000 US gallons (16,653 Imperial gallons or 75,708 liters). They also moved 30,000 cubic yards (22 937 cubic meters) of coral fill in the construction of a 2,200-foot (671 meter) causeway at the western end of the Hawkins Field.
     Naval Air Base and Marine Corps Air Base Betio were established on 1 April 1944 and served as the principal base for bombing and harassment raids on Japanese bases in the Marshall Islands and Nauru Island. The NAB and MCAB portion of the airfield was disestablished on 9 December 1944, as the progress of the war moved the advanced bases further afield from Betio. Hawkins Field was turned over to the USAAF Air Transport Command on 1 June 1945.
     After the war, Hawkins Field was abandoned and there are few traces of it visible from above while the former Mullinix Field is now Bonriki International Airport.