Bismarck Archipelago
by Jack McKillop

Physical Description & History

     The Bismarck Archipelago is a group of islands in the western Pacific off the northeastern coast of New Guinea between 1°00'S and 6°20'S, and 145°E and 154°E. The total area of these islands is 19,173 square-miles (49,658 square-kilometers). The main islands are New Britain (the largest), New Ireland, New Hanover, the Admiralty Islands, the Vitu Islands, the Saint Matthias Group and about 200 others.
      In 1884, the German New Guinea Company raised the German flag over Kaiser-Wilhelmsland (New Guinea), the Bismarck Archipelago and the German Solomon Islands (the northern Solomon Islands: Bougainville, Buka, Choiseul, Ontong Java and Santa Isabel). On 1 April 1899 the German government formally took control of these lands, and the area became a protectorate until it was occupied in September 1914 by the Australians during World War I. After the war, the League of Nations established mandates whereby territories controlled by Germany and the Ottoman Empire were given to Allied nations. The islands of the Bismarck Archipelago were one of the mandated territories given to Australia in 1920 as the Australian Mandated Territory of New Guinea.
     During World War II, the U.S. Navy built two bases in two of the island groups, the Admiralty Islands and the Saint Matthias Group. The Admiralty Islands (2°05'S, 146°52'E) are a group of 40 volcanic islands located north of New Guinea, about 240-miles (386-kilometers) northwest of Rabaul, New Britain Island. Total land area is 810 square-miles (2,098 square-kilometers). The two largest islands are Manus (the largest) and Rambutyo and there is about 16 smaller islands including Los Negros Island which is separated from Manus by a narrow passage.
     The Saint Matthias Group (1°37'S, 149°47'E), also known as the Mussau Islands, are two small volcanic islands and several coral islets located about 70-miles (113-kilometers) northwest of New Hanover Island. The two islands are Mussau, the largest, and Emirau.
     In 2011, the Bismarck Archipelago is part of the Independent State of Papua New Guinea. Manus Island is part of Manus Province and Emirau Island is part of New Ireland Province.

Emirau, Naval Advance Base

     Naval Advance Base (NAB) Emirau (1°39'S, 149°59'E) was built on Emirau Island in the Saint Matthias Group. This island is 8-miles (13-kilometers) long and 4.5-miles (7.2-kilometers) wide at the center of the island for a total land area of 20 square-miles (52 square-kilometers). The island is located 231-miles (3,722-kilometers) northwest of the Japanese bases at Rabaul on New Britain Island while Truk Atoll in the Caroline Islands is 632-miles (1,017-kilometers) north.
    Two battalions of the 4th Marine Regiment invaded this unoccupied island on 20 March 1944 to close off the approaches to the Japanese bases at Kavieng, New Ireland Island from the north. Several days later the Seabees arrived and began construction of two air bases for the shore-based bombers in the coming attacks on Truk Atoll, Yap Islands, and the Palau Islands in the Caroline Islands. In addition to landing fields, the island was to be developed as a naval base, a motor torpedo boat (PT) operating base, and a minor repair base. NAB Emirau was commissioned on 28 April 1944.
     The two parallel airfields, Inshore and North Cape (1°39' 05"S,  149°58' 03"E), were both heavy bomber strips, 7,000- by 150-feet (2,134- by 46-meters), and coral surfaced, as were the warm-up areas at each end of the fields. Inshore Field had 35 double hardstands capable of parking 210 fighters or light-bombers; there were 42 hardstands on North Cape Field, with space for parking 84 heavy bombers. Both fields had all necessary facilities for operations, including a control tower, field operations building, field lighting, and a dispensary. All buildings used for supplies and servicing were of prefabricated steel or wooden frame.
     A tank farm for aviation gasoline was installed with three 10,000-barrel and nineteen 1,000-barrel tanks, two tanker moorings with anti-torpedo nets, two sea-loading lines, and a gravity distribution system to six truck-filling points. In connection with this farm, an adequate reserve of more than 40,000 barrels was maintained in drums. The ammunition and bomb dump provided covered storage, steel magazines, and revetments.
     Three hospitals were built on the island. The naval base hospital, with a capacity of 100 beds, and an Army hospital, with beds for 160, were both located in the southwestern tip of the island. 
     The anchorage in Hamburg Bay (1°39'S, 149°57'E) accommodated five capital ships; Purple Beach, on the Bay, with three finger piers and one 77- by 120-foot (23- by 36-meter) slip were sufficient to handle seven landing craft, tanks (LCTs). On this beach were also eight pier cranes, refrigerators with a capacity of 42,400 cubic-feet (1,201 cubic-meters), six 40- by 1,000-foot (12- by 305-meter) warehouses, and approximately 400,000 square-feet (37,161 square-meters) of open-storage space, which permitted the handling of 800 tons (726 metric tonnes) of cargo a day. An LCT floating drydock was also maintained in the Bay. All other beaches on the island were unsuitable for efficient cargo handling; however, five beaches on the western coast were improved to accommodate thirteen LCT's.
     Communication facilities consisted of two wooden transmitter buildings with concrete floors, two 16- by 32-foot (4.9- by 9.8-meter) revetted wood-frame power plants, and two Quonset-type receiver stations.
     The naval base was established at the southwest tip of the island. Facilities constructed for its operation consisted principally of wooden frame, canvas-covered structures, replaced later by Quonset-type buildings, when urgent airfield facilities had been provided.
     Quarters and messing for 560 officers and men, engine overhaul and repair shops, a magazine, a total of 350-feet (107-meters) of coral-fill piers, a signal tower, and all the necessary utilities for a PT base, were erected on the island of Eanusau (1°41'S, 149°54'E), just off the southwest tip of Emirau. The small-boat pool was also installed there, consisting of a camp for 250 men and 15 officers, four Quonset-type dry-storage buildings, shops, a sick bay, an armory, a generator plant, ships' service, a personnel pier, and a signal tower. Connecting the various activities and camps were a total of 40-miles (64-kilometers) of 40-foot (12-meter) wide coral-surfaced, all-weather highway.
     For the rest of the war, Navy and Marine aircraft based on Emirau attacked the major Japanese base at Rabaul, New Britain Island while the U.S. Army Air Forces used it to bomb Truk Atoll in the Caroline Islands.
     As the war moved west, the need for bases like this diminished. The PT-boats ceased operating on 24 November 1944 and their base was rolled up in early December. The remaining facilities were dismantled and the naval base was disestablished in March 1945.
     In 2011, the Saint Matthias Group is a province of Papua New Guinea.

Manus, Naval Operating Base

     Manus and Los Negros Islands comprise the major islands of the Admiralty Island group, which includes some 16 small islands and atolls and three first class harbors.
     Manus Island (02° 05' S, 146° 58' E), the largest island in the Admiralty Islands, is 50-miles (80-kilometers) long and 20-miles (32-kilometers) wide for a total area of 633 square-miles (1,639 square-kilometers). A 2,355-foot (718-meter) high mountain range extends over the entire length of the island. Manus is located 247-miles (347-kilometers) west of Kavieg, New Ireland Island, and 200-miles (322-kilometers) west of Emirau Island.
     Los Negros Island (02°02' S, 147°25' E) is located off the eastern coast of Manus Island and the two are separated by no more than a narrow, creeklike strait that in some places is only 100-yards (91-meters) wide. Its horseshoe curve from the east encloses the natural Seeadler (German for sea eagle) Harbor, which finds further protection in a string of small islands running parallel to the northern shore of Manus. The harbor is approximately 6-miles (9.7-kilometers) wide and about 20-miles (32-kilometers) in length and affords anchorage for large vessels.
     A Japanese Army battalion occupied Manus Island on 8 April 1942 and over the next two years, the Japanese built three airfields, one on Manus and two on Los Negros. Lorengau Airfield
(2° 01' 13"S, 147° 15' 59"E) was located at Lorengau on the north coast of Manus Island parallel to Seeadler Harbor. The small Japanese airfield, with a single runway running north-northwest to south-southeast, was 3,500- by 375-feet (1,067- by 114-meters) with 20 fighter revetments along the southern end of the runway. A road connected the strip to a nearby jetty to the east, that continued to the town of Lorengau.
     On 15 March 1944, elements of the U.S. Army’s 1st Cavalry Division landed 3,000-yards (2,743-meters) west of Lorengau Airfield on the north shore of Manus Island. The north coastal area of Manus was cleared by May.
     The Japanese airfield on Manus, Lorengau, was evaluated and was found not to meet the requirements of American forces for airfield development, and was not used as a major airstrip.
     The principal installation on Manus Island was Naval Operating Base (NOB) Manus. Facilities were made for a supply depot, which was to serve shore based activities in the Admiralty Islands as well as all forces afloat in the area. The Seabees erected 128 storage buildings, 50 refrigerators, each containing 6,800 cubic-feet (193 cubic-meters), open-storage areas, 5-miles (8-kilometers) of access roads, a tank landing ship  (LST) landing beach, and two major piers, one 800-feet (244-meters) and the other 500-feet (152-meters) long. Ultimately, the storage floor space was extended to give the equivalent of 180 storage buildings. This was accomplished by lean-to additions that were located along the Lorengau airstrip.
     A major development undertaken at NOB Manus naval base was the construction, operation, and maintenance of a water-supply system, capable of producing 4 million US gallons (3.3 million Imperial gallons or 15.14 megaliters) per day.
     The administration area for the entire NOB Manus base was located at the mouth of the Lorengau River on Manus. Facilities included 48 Quonset huts for officers, a 2,000-man mess hall, ten Quonset huts, signal towers for base communications, all utilities, and a timber pier.    Original plans contemplated two separate hospitals, but these were consolidated into one 1,000 bed unit. Facilities included 42 Quonset huts, a 1,000-man mess hall, eight wards, five operating rooms, storage facilities, administration, dental, and laboratory installations, and all utilities. A receiving station was also established, containing facilities for 5,000 men in 292 Quonset huts, with frame galleys and mess halls.
     The Japanese had built two airfields on Los Negros Island, Mokerang and Momote. Mokerang Airfield (1°58' 44"S, 147°22' 13"E) was the first built and was located at the tip of Los Negros on the prewar Mokerang Plantation. The second airfield was Momote Airfield (2°03' 43"S, 147°25' 27"E) known to the Japanese as Hyane Airfield. This airfield was located at the eastern side of Los Negros, spanning from Hyane Harbor to the Bismark Sea. Momote Airfield was 4,100- by 300-feet (1,250 by 91-meters) with three taxiway areas, and 12 revetments under construction.
     On 29 February 1944, Navy Task Group 76.1 comprising nine destroyers and three high speed transports, landed elements of the U.S. Army’s 1st Cavalry Division on Los Negros at Hyane Bay near Momote Airfield. Two Australian heavy cruisers, HMAS Australia (D84) and HMAS Shropshire (83), and four USN destroyers of Task Force 74 provided cover and bombard Japanese positions on Los Negros and Manus.
     With the capture of these two islands, the island of Los Negros was turned into a major installation. NOB Manus and Naval Air Facility (NAF) Manus Island were established on 18 May 1944. Construction of a major naval and air base, capable of service, supply, and repair to forces afloat, air forces, and other Allied units in the forward area, was begun. The first job was to rehabilitate Momote Airfield. The condition of the airfield was such that 14,000 cubic-yards (10,704 cubic-meters) had to be filled and graded before matting could be laid, as local coral material proved unsuitable as surfacing. When completed, the airfield was 7,800- by 150-feet (2,377- by 46-meters), with taxiways and hardstands for 90 fighters and 80 heavy bombers, a 17,000-barrel aviation-gasoline tank farm with fuel jetty for small tankers, bomb storage revetments, roads, operations buildings, and personnel facilities.
     Three Royal Australian Air Force fighter squadrons, No. 76, 77 and 79 were tasked to provide close air support for ground troops, air defense of the air bases and shipping escorts. The first squadron had arrived at Momote by 29 March with Kittyhawk fighters. The first U.S. Army Air Forces (USAAF) B-24 Liberator squadron arrived on 13 April.
     Mokerang Airfield was also improved. When finished the airfield had a bomber runway, 8,000- by 200-feet (2,438- by 61-meters), a taxiway, 8,500- by 125-feet (2,591- by 38-meters), with hardstands and service areas for 50 bombers. The first U.S. Army Air Forces (USAAF) B-24 Liberator arrived on 21 April. The original taxiway was later enlarged and two additional taxiways built. Other installations included a 30,000-barrel tank farm, Quonset-hut shops, and personnel facilities. A second runway was later added. This airfield was completed on 22 April and four squadrons of B-24 Liberators of a second bombardment group arrived on 13 May.
     By August 1944, the two USAAF B-24 groups had left Los Negros Island for Wakde Island in the Netherlands East Indies (NEI, now Indonesia) (q.v.).
     NAF Manus (Lombrum Seaplane Base) (2°02' 21"S, 147°22' 29"E)  was the main seaplane  base for the area. This base was near Lombrum, Los Negros Island with the seaplane anchorage and landing area located in adjacent Seeadler Harbor. The base was established to furnish operational, service, and repair facilities for seaplanes. Installations included a 50- by 250-foot (15- by 76-meter) concrete seaplane ramp, one steel nose hangar with a concrete deck, an 8,000 barrel aviation gasoline tank farm, a pontoon pier for small boats, four 40- by 100-foot (12- by 30-meter) prefabricated shops, Quonset-hut shops, and camp facilities.
     On 25 March 1944, Navy Patrol Squadron Thirty Three (VP-33), equipped with PBY-5A Catalinas, was relocated to NAF Manus. There it conducted daylight searches toward Truk Atoll and Woleai Atoll in the Caroline Islands; bombing missions against Woleai and Wakde Island in the NEI; air-sea rescue missions around Truk, Woleai and Yap Island in the Caroline Islands; and coverage for the invasion of Hollandia in the NEI. On 18 September 1944 VP-52 with PBY-5 Catalinas began operating from NAF Manus Island, with rotation of detachments to Treasury, Green and Emirau islands.
     In addition to the air bases, a number of other facilities were built in the Hyane Harbor area of Los Negros (2°03'S, 147°26'E), including a 500 bed evacuation hospital for the Army. Waterfront construction consisted of two cargo-ship wharves, a repair pier with fixed crane, and a fuel pier, 800-feet (244-meters) long, to serve major ships. Facilities at the pontoon assembly depot involved a pontoon pier, four prefabricated steel buildings for warehouses, shops, and offices, structural steel factories, and a personnel camp of 40 huts with all utilities for 50 officers and 500 men. The depot could assemble 900 pontoon cells per month.
     An aviation supply depot was established as the central procurement, storage, and issuing agency for all such material and equipment in the Southwest Pacific area. For this activity, 24 steel warehouses were built, each 40- by 100-feet (12- by 30-meters), and 83 Quonset huts for administration and personnel. Facilities for an aviation repair and overhaul unit were set up, consisting of 25 steel buildings, 40- by 100-feet (12- by 30-meters), for shops, a personnel camp for 1,000 men, roads, and all utilities. The section base at Hyane Harbor was provided with facilities for small-boat repair, including a wharf, personnel camp, and shops.
     Two additional locations on Los Negros were selected for development, one at Papitalai Point and one at Lombrum Point. The major project at Papitalai, a tank farm with sufficient storage of fuel and diesel oil to supply a large base and major units of the fleet, was begun on 23 June. Lack of suitable coral for surfacing again proved a handicap. Material for tank foundations had to be ferried across the harbor, and roads deteriorated to such an extent that corduroying was the only solution. However, the schedule to complete 235 tanks by 15 August was met despite the difficulties encountered, and work continued until 63 tanks were erected, each having a 10,000 barrel capacity. A two-way pumping system and a drum-filling plant completed the farm, which was split into sections, making it possible to operate from any single unit or series of units.
      In addition to the seaplane repair base at Lombrum Point described above, a landing-craft repair base was built consisting of six warehouses and shops, two Quonset huts for administration buildings, and frame quarters and messing facilities, with all camp utilities. A 250-ton (227-metric tonne) pontoon drydock was provided for docking landing craft, tanks (LCTs), medium landing ships (LSMs), and smaller landing craft. Facilities at the ship repair base combined docking, repair, and supply services equivalent to those furnished by auxiliary ships. Docking equipment consisted of a 100,000 ton (90,718 metric tonne) sectional dock capable of handling battleships, a 70,000 ton (63,503 metric tonne) sectional dock capable of handling most major ships, and an 18,000 ton (16,329 metric tonne) steel floating dock.   
     Two additional air bases were constructed on the nearby small islands of Ponam (1°54' 49"S, 146°53' 04"E) and Pityilu (1°57' 43"S, 147°13' 25"E) located off the northern coast of Manus Island. At Ponam a fighter base, to provide minor repair and overhaul facilities for carrier-based planes, together with housing facilities for pilots and crews, was established. Installations consisted of a coral surfaced airstrip, 5,000- by 150-feet (1,524- by 46-meters), a 5,000-foot (1,524-meter) taxiway with a parking area 6,000-feet square (557-meters square); 34 Quonset huts for repair shops and operations; a 1,500-man camp; and an 8,000-barrel tank farm with sea-loading line for aviation gasoline. Fifty per cent of the work area was swamp land, requiring fill, all of it coral, blasted and dredged from the ocean bed.
     The base on Pityilu Island was to care for one patrol squadron, to service and repair all types of carrier based planes, and to provide storage for 350 of these planes, with camp accommodations for 350 officers and 1,400 men. The coral-surfaced runway measured 4,500- by 300-feet (1,372- by 91-meters), with taxiway and three parking areas. Prefabricated steel huts were erected for administration, operations, and shop use. Other facilities included a 7,000 barrel aviation gasoline tank farm with sea loading line, one prefabricated nose hangar, and munition dumps. This work was accomplished in May and June 1944. Later, the field was extended 1,000-feet (305-meters); parking areas were increased; the camp was enlarged to accommodate 2,500 men; and the dispensary was developed into a 100 bed hospital with all facilities. The eastern end of Pityilu Island was cleared, graded, and made into a fleet recreation center to accommodate 10,000 men at a time.
     On 10 November 1944, ammunition ship USS Mount Hood (AE-11), anchored in about 19 fathoms (114-feet or 38-meters) of water, was destroyed by accidental ammunition explosion in Seeadler Harbor. The cataclysmic blast damaged nearby escort aircraft carriers USS Petrof Bay (CVE-80) and Saginaw Bay (CVE-82); destroyer USS Young (DD-580); destroyer escorts USS Kyne (DE-744), Lyman (DE-302), Walter C. Wann (DE-412), and Oberrender (DE-344); high speed transport USS Talbot (APD-7); destroyer tender USS Piedmont (AD-17); miscellaneous auxiliary USS Argonne (AG-31); cargo ship USS Aries (AK-51); attack cargo ship USS Alhena (AKA-9); oiler USS Cacapon (AO-52); internal combustion engine repair ships USS Cebu (ARG-6) and Mindanao (ARG-3); repair ship USS Preserver (ARS-8); fleet tug USS Potawatomi (ATF-109); motor minesweepers YMS-1, YMS-39, YMS-49, YMS-52, YMS-71, YMS-81, YMS-140, YMS-238, YMS-243, YMS-286, YMS-293, YMS-319, YMS-335, YMS-340, YMS-341, and YMS-342; unclassified auxiliary USS Abarenda (IX-131), covered lighter YF-681, and fuel oil barge YO-77. USS Mount Hood had an estimated 3,000 tons (2,722 metric tons) of explosives on board, and except for a working party from the ship that was ashore at the time, her entire ship's company perished. Mushrooming smoke rose to 7,000-feet (2,134-meters), obscuring the ship and the surrounding area for a radius of approximately 500-yards (457 meters). The force of the explosion blasted a trough in the harbor floor longer than 100-yards (91-meters) and 50 feet (15-meters) wide and 30- to 40-feet (9.1- to 12-meters) deep; some fragments landed more than 2,000-yards (1,829-meters) from where Mount Hood lies. Investigators found no fragment of the ship on the ocean floor larger than 16- by 10-feet (4.9- by 3.0-meters). In terms of the extent of damage, it ranges from an estimated 48,000 man-hours to repair USS Mindanao (which suffered 23 dead and 174 injured) to "superficial" or "insignificant." In addition to the ships listed above, nine medium landing craft (LCM) and a pontoon barge moored to Mount Hood are also destroyed; 13 small boats or landing craft are sunk or damaged beyond repair, 33 are damaged but repairable.
     Early in 1945, fleet support activities moved westward to Ulithi Atoll, Guam and the Philippine Islands. On 29 April, Japanese Kate torpedo bombers (Nakajima B5N, Navy Type 97 Carrier Attack Bombers) flying from Truk Atoll attack NOB Manus torpedoing the advance base section docks ABSD-2 and ABSD-4 in the belief that the shapes they perceived in the nocturnal strike are aircraft carriers.
     NOB Manus and NAF Manus Island were disestablished on 1 September 1947.
     In 2011, the Admiralty Islands are part of Manus Province of Papua New Guinea.