The island of Borneo is the second largest island in the East Indies, second only to New Guinea. Although it possessed raw materials in abundance, the most important of these were rubber and petroleum. Facilities for the production of petroleum and rubber were situated along the coast, with most of the interior inhabited only by indigenous peoples. Therefore the campaign to re-establish Allied control of the island focused on the perimeter of the island using amphibious assaults to provide access to the desired areas.
Earlier in the war the Japanese had taken over these areas from the Dutch and English for the purpose of obtaining raw materials unavailable in their home islands. Among them were Borneo’s rubber and petroleum. The two centers of petroleum production, Balikpapan, on the Dutch-held southern part of the island, and the British-controlled areas of Brunei, Sarawak, Labuan, and North Borneo on the northwest coast, were prime targets of the Japanese and fell under their control early in 1942.
Where Borneo lay in the grand strategy was under consideration by the Joint Chiefs of Staff:
The campaign that had led to the invasion of Luzon and was oriented northward toward Japan itself had resulted in the bypassing of the largest portions of the Netherlands East Indies. Although rich in resources for war, notably oil, rubber, and manganese, strategically the islands were of minor importance in the pattern set for the defeat of Japan. The Japanese depended upon them for vital supplies; but U.S forces did not need them sufficiently to warrant diverting resources to occupy any of the islands. At the beginning of February 1945, as the end of the major campaign in the Philippines came in sight, General MacArthur began to think of the desirability of seizing Borneo and acquiring its oil for use in the attack on Kyushu and Honshu. To the Joint Chiefs of Staff, then at Yalta, he reported that he was planning amphibious operations into Borneo that would be launched about 1 April 1945, using Australian troops.1
The liberation of Borneo had been put off by the Allied forces for several reasons, among them the overwhelming desire of General Douglas MacArthur to recapture the Philippines and the effectiveness of the U.S. Navy in cutting the Japanese supply lines. In addition, the island was far within the borders of the rapidly-expanding Japanese empire and a campaign in 1943 or 1944 was impractical. By 1945, little of the much-needed oil from Borneo was reaching the home islands of Japan thanks to an effective campaign by American submarines, surface ships, and aircraft. With success in the Philippines imminent, the attack on Borneo was planned. American forces had been committed to the taking of Okinawa, and the British desired to participate in that conquest as well. This fit in well with the planning of the Joint Chiefs of Staff who wanted the British to assume more responsibility for actions in the Southwest Pacific. They planned to transfer some of the area to British control. “The area transferred might be bounded by a line approximately from a point on the China coast between Indo-China and China southeastward through the Balabac Strait to the Equator and thence eastward.”2 This transfer would place Brunei Bay, Borneo, under their control and the British could use it as a home base. However, the British saw this as a move designed to keep them away from the eventual battle for Japan proper.
The battle for Borneo was fought by the Australians. In part this was a political move designed to assuage Australian feelings that they had been left out of the main part of the war. In his report to the Joint Chiefs of Staff, “General MacArthur reported that the Australians were becoming restive because their troops were not in action.”3 Not only were the Australians feeling left out, they wanted to be a part of the actual drive on Japan. Operations against bypassed groups of Japanese left behind in MacArthur’s island-hopping campaign had given them the feeling that they were being relegated to what were basically insignificant duties. At the Australian War Cabinet meeting of 28 May 1945, it was noted that:
There have been criticisms that the liquidation of by-passed Japanese forces is not by itself a worthwhile effort of our forces. The reasons for the non-participation in the Philippines campaigns have been made clear. But with American progress towards Japan, the operations against Borneo, the N. E. I. and Malaya, have assumed the nature of large-scale mopping-up campaigns. From the aspect of prestige, it is of greater importance to Australia to be associated with the drive to defeat Japan, though for reasons of British and Australian prestige, it would be desirable to have a token force in the recapture of Malaya, in order to avenge the defeat of 1941.4
Therefore Australian troops, aided by American, Australian, New Zealand, and Dutch Navy vessels, would take Borneo back from the Japanese. Involved in the assault on Borneo was the Australian Army’s 1st Corps under Lieutenant General Sir Leslie Morshead, which consisted of the 7th and 9th Divisions. Support for the troops was supplied by the Royal Australian Air Force’s 1st Tactical Air Force and the U.S. 13th Air Force. Elements of the Royal Australian Navy, elements from New Zealand’s forces, and the U.S. Navy provided ships and gunfire-support. Originally six landings designated as Oboe I through VI were planned, but only three were used. Between 27 April and 20 July 1945, the Allied forces staged three operations: Oboe I, VI, and II. Oboe I, the landing at Tarakan, began on 1 May 1945. Oboe VI, the landing at British North Borneo, began on 10 June when Australian troops landed at Labuan Island in Brunei Bay. Oboe II took place on 1 July, with the Australians landing over 33,000 troops and support personnel at Balikpapan. In all cases the landing date was preceded by several days of minesweeping, UDT work, and naval and aerial bombardment of selected targets.
Major obstacles to the landings existed and included underwater beach obstructions. In addition, the Dutch, Americans, and finally the Japanese, had completed extensive mining operations off the beaches, and these had to be swept prior to any attempt to land troops. This stood in stark contrast to landing in the Philippines where such measures had not been taken by the Japanese. Underwater demolition teams and YMS minesweepers were in action several days prior to the actual invasion date, clearing mines and obstacles from the landing zones. YMSs would have to operate literally under the guns of the Japanese defenders, and several were sunk either by striking mines or being shelled by shore positions. LCPRs carrying UDT units operated close in to shore, covered by LCS(L)s and other fire-support craft. Their task was made even more difficult by errant aircraft bombing, poisonous sea snakes, and saltwater alligators. The frogmen operated within a few hundred yards of the beach and the gunboats were not far away, placing them in imminent peril from shore batteries. In Borneo, thirty-eight minesweepers from Mine Division 34 were used. Working in conjunction with the minesweepers were the LCS(L) gunboats.
Participating in the attack on Borneo were various elements of the amphibious gunboat units, including LCS(L)s 8, 28–30, 41–48, 50, 58–60, LCI(R)s 31, 34, 71, 72, 74, 226, 230, 331, 337, 338, LCI(G)s 21–24, 59, 61, 64–70, and LCI(M)s 359, 362, and 431.
By mid–1944 the island of Borneo was under attack by Australian forces supported by the United States Navy and Army Air Forces. Numerous LCS(L)s and LCI gunboats were used in the four main assaults on the island. Adapted from OCE, GHQ, AFPAC (Historical).
Tarakan Island is on the eastern coast of Borneo in the area previously under the control of the Dutch. It is approximately eleven miles wide and fifteen and one-half miles in length. The only access to the island was at the port of Lingkas which contained a pier used for docking tankers. Nearby beaches were of dubious value, heavily mined, and contained numerous obstacles constructed by the Japanese to discourage landings. However, the airfield at Tarakan was a prime target. If the island and its airfield could be captured, it would serve as a base for Allied aircraft in the campaigns in Borneo that would follow. Since it had been a Dutch possession, a contingent of Dutch troops accompanied the Australians in the landing. A Japanese garrison, estimated to be 2,300 strong, occupied the area. Defenses on the island were otherwise minimal, with only six coast defense gun emplacements.5 Air support for the operation was supplied by the R.A.A.F.’s 1st Tactical Air Force and the U.S.’s 5th and 13th Air Forces. The air operations were under the command of Air Vice-Marshal Bostock.
Rear Admiral F. B. Royal, Vice Admiral Daniel E. Barbey, and Rear Admiral A. G. Nobel on 26 March 1945. NARA 80G 328150.
The air attacks against Tarakan began on 12 April with P-38 Lightnings of the 13th Air Force staging a raid against enemy positions on south Tarakan. From then on until the invasion, regular flights of B-24s, B-25s, Lightnings, and Beaufighters made regular attacks on Japanese positions at Tarakan, making sure to eliminate the oil storage tanks and as many gun emplacements as possible.
Headquarters for planning the Tarakan campaign were on the island of Morotai. Once the plans had been finalized, the landing craft were run through their paces in a preliminary rehearsal which took place between 19 and 24 April. Larger ships from Rear Admiral R. S. Berkey’s cruiser covering group headed south from Subic Bay, while minecraft and hydrographic ships set forth from Leyte. Still other ships, like LCI(M) 359, set out from diverse locations, such as Tawi Tawi Island, and headed for Borneo. On the way to Borneo, the 359 encountered two rafts with eight Japanese on board. They called for them to surrender, but two of the Japanese blew themselves up with hand grenades and the others appeared about to throw them at the ship. The enemy soldiers were cut down by .50 caliber gunfire from the gunboat. Only one survived. He threw up his arms while in the water and it was assumed that he wanted to surrender. He climbed aboard the raft. Men on board the gunboat kept a wary eye on him, and it was fortunate that they did. Once on the raft, he suddenly crouched down and began searching for something on the deck. Suspecting that he was looking for another grenade, the gunboat’s crew opened fire and killed him.6
An LCI gunboat fires rockets at Tarakan. Official U.S. Navy photograph.
Not all of the days in the Pacific were filled with action. Here crew members on LCS(L) 28 stand watch in their foul weather gear off Tarakan Island on 29 April 1945. Official U.S. Navy photograph.
Australian engineers wade ashore on Red Beach at Tarakan to set explosives on 30 April 1945. NARA 80G 359858.
The Consolidated B-24L Liberator was used in the Pacific by both the Americans and the Royal Australian Air Force. This photograph was taken in 1944.
Australian troops of the 26 Australian Infantry Brigade, 9th Australian Army Infantry Division, wade ashore at Tarakan on 1 May 1945. The division was commanded by Brigadier David A. Whitehead. Rows of pilings designed to stop landing craft are visible just offshore. Australian engineers, using demolitions, blew gaps in the obstacles to allow landing. NARA 80G 259353.
RAAF Bristol Beaufighters 50 TU A19 MKI in training formation over Waga Waga, New South Wales, Australia.
These varied elements of the attacking force rendezvoused off Tarakan on 27 April. A task group under Rear Admiral F. B. Royal arrived on 1 May to lead the landings. A predictable fatalism came over the gunboat crews and was demonstrated by EM 3/c Raymond J. Ross when he wrote: “Reports have it that the LCS’s don’t last long, many were said to have been sunk at Iwo Jima for they are the first to enter a battle zone along with mine sweepers to draw fire from the beach in order to find the strength of locations of the opposition. Will know all about it in a few days.”7Ross was a bit mistaken about the identity and number of the ships lost at Iwo Jima; they were actually LCI(G)s and only one was sunk. But the comparison was close enough since both types of gunboats would always be in the hazardous first line of fire.
The actual assault on Tarakan began with minesweeping operations. Assigned to the chore was TU 78.1.5 Minesweeping Unit under Lieutenant Commander James R. Keefer. The task unit consisted of Cofer APD 63, which acted as the flagship, four minesweeping LCVPs, and ten YMSs. Their mission was to clear Tarakan’s channels, approaches, anchorages, and landing beaches of mines. Numerous enemy minefields had been reported, and suicide boats and suicide swimmers were also suspected to be in the area. It was also known that the Japanese had shore batteries that could easily hit the small ships as they performed their hazardous work.
LCS(L)s 8, 28, 43, 44, 48, and 50 were on hand to protect the minesweepers. The first day of sweeping, 27 April, was uneventful with the LCS(L)s destroying mines that had been cut loose. However, on 28 April, YMS 329 hit a magnetic mine and suffered nineteen casualties. The severely damaged minesweeper was forced to retire from her assignment. A couple of days later, YMS 51 set off another magnetic mine and sustained minor damage. Close calls were the order of the day. Robert C. Heim who served as BM 2/c on LCS(L) 48 later wrote, “while following the minesweepers a mine came up off our bow—everyone ran aft for fear it would blow up. After it grazed the ship without going off it was shot out of the water with our 20mm and 40mm.”8 Jenkins DD 447, cruising in the area, also was damaged when she set off a contact mine. At 1530 on 2 May, the minesweepers took significant damage from the shore batteries at Cape Djoeata with YMS 481 sunk and YMSs 334 and 364 hit. Cofer APD 62 and the LCS(L)s took the shore batteries under fire and put them out of commission. In addition, YMS 363 detonated a mine during her operations and sustained damage as well.
Nearby Sadau Island was identified as a likely place to set up artillery batteries for bombardment of the beaches around Tarakan. Philip DD 498 bombarded the landing area while LCS(L)s 48 and 50 made a rocket run on the beaches to cover the Australian landing, which took place around 0900. Following that, the LCS(L)s went to the aid of the Royal Australian Engineer Demolition Party which was landed near the Linkas area. Lieutenant (jg) Joseph E. Rhoads, who served as Engineering Officer on LCS(L) 50, described them as “ a ruddy and zealous bunch.”9 They promptly set about blowing up the beach obstacles in preparation for the next day’s landing as the gunboats provided covering fire. Small arms fire emanated from shore and placed the engineers in peril. The LCS(L), along with a nearby destroyer, took them under fire and put an end to the threat. The next task for the gunboats was a cruise along the south coast of Tarakan where they fired on several luggers and some shore installations.
The scheduled date for the landings on Tarakan was 1 May 1945. The 26th Australia Infantry Brigade was a part of the 9th Australia Infantry Division commanded by Brigadier David A. Whitehead. Landing on the beaches at Tarakan were 18,000 men, including 500 U.S. Army personnel and about 400 Dutch whose task would be to re-establish Dutch administration in the area.
Air support for the assault was provided by the 13th Air Force and the R.A.A.F., whose B-24 Liberators, B-25 Mitchells, and P-38 Lightnings bombed Japanese installations and provided close-in support over the beaches just prior to the landing. Aircraft from the Royal New Zealand Air Force and American aircraft also participated, but under the direction of the Australians. During the attack on Tarakan, the supporting aircraft flew off the fields on Morotai.
While the LCS(L)s were providing cover for the minesweepers and Australian engineers, other ships got underway from Morotai. Close Fire-Support Unit 78.1.3 under Commander D. H. Day, consisting of LCS(L)s 8, 28, 43, 44, 48, 50, LCI(R)s 71, 72, 74, 338, LCI(M)s 359, 362, LCI(D)s 29, and 228 headed for the assault.
On Peter Day (1 May 1945), the ships deployed at 0515 and began their first rocket run against the landing zone. Following the launching of their rockets, they fired on the beaches with their 3"/50 and 40mm guns and then circled back to await the landing of the Australian troops. Strong currents in the area pushed the landing craft to the right of their assigned location, and they had to do some hard last minute maneuvering to make it to the landing zone. In his action report of 1 May 1945 Lieutenant C. C. Henson, the Commanding Officer LCI(R) 71, recommended that the landing craft “be directed to follow the support craft and allow the support craft to determine the course for them, particularly when strong currents are present as was the situation during this assault. This will insure the troops the full effect of the fire-support offered by rocket ships.”10
Australian and Dutch troops landed to light opposition and were soon in control of the island. The airfield had been seen as an important prize but it proved to be relatively worthless. It had fallen into disuse and had been damaged by the bombings and by naval ship fire. In addition, it was a wet area and would need much work before it could serve as a base for further campaigns.
The mortar ships had a role in the invasion as well. One suggestion for their improvement came from Lieutenant H. A. Peterson, CO of LCI(M) 362. He suggested:
It is recommended if at all possible that the mortars be mounted on turntables with a 95 degree deflection to either side of ships center line. It has been found that due to the limited amount of deflection in these weapons this vessel is a menace to the wave guide line of support craft when assigned to accompany them in. Also that a set from the same direction as the flank assigned reduces the output. With turntables an effective broadside of at least two weapons could be obtained, it would also permit this type of vessel to anchor close-into the beach and provide more accurate support fire than could be obtained at present.11
Although the initial assault on the Brunei Bay area was scheduled for 10 June 1945, preliminary air strikes were needed to reduce Japanese resistance in the area. The task was assigned to the 1st Tactical Air Force and the 13th Air Force. Two units of the 5th Air Force, the 90th and 380th Bomber Groups, were temporarily assigned to the 13th Air Force to bolster its striking power. In addition to bombing targets in the Brunei Bay area, they also flew missions against enemy emplacements at Balikpapan. Beaufighters of the Nos. 22 and 30 Squadrons R.A.A.F. were active on 3 June, bombing and strafing oil tanks at Bangsal and strafing and bombing Brunei town. From that point on, both American and Australian air units conducted missions against the Japanese in preparation for the assault and in support of the troops once they landed.
A pair of LCS(L)s attack Japanese positions on the beach as they lead Australian landing craft in the assault on Borneo. Official U.S. Navy photograph.
The landings in and around Brunei Bay, including Labuan Island and Muara Island, were scheduled for 10 June. On that day there were three simultaneous landings at the north shore of Victoria Harbor, the east shore of Muara Island, and the north shore of Cape Polompong which lay to the east of Brunei Bluff.
The gunboats arrived in the area three days prior to the actual landings to assist in minesweeping and to cover UDT operations. While this had its usual share of risks, they could occur at strange times. Gilbert Nadeau, a signalman on LCS(L) 45 later recalled:
Our first night out, at approx. 9:00 PM, we were informed via the PA system that we had inadvertently sailed into a Jap minefield and were in it—like right now!! My ship was the #45. When the announcement was made I and another shipmate were seated “on the trough” in the head. My shipmate was a lean, lanky guy, wearing nothing by sea-bees shoes (rough leather, high topped, heavy soled shoes), undershorts and well-worn raggedy dungarees—which at that time were both down at his shoe tops. Suddenly we heard a loud metallic thump/clanging coming from under the ship towards the bow. My shipmate got real startled, cursed and said, “Shorty—do you think that’s what I think it is??” I replied “cripes yes!! Sounds like we just run over a mine!!”
Just about that time—and this time just about amidships (where we were still sitting in the head)—The metallic bump & scrapping & clanking happened again. This time my shipmate cursed, jumped straight up so fast he left his shoes, shorts & dungarees right there on the deck where his feet were—and flew out of the head & headed aft. Seeing this happen—jumping out of shoes, shorts & dungarees like a Mack Sennet cartoon—and heading aft bare naked I laughed so hard & so much I couldn’t have run even if I had wanted to!! A minute or so later the banging, scraping, clanging sound came again—aft. We had definitely run over a mine!! A couple of minutes later my shipmate returned—nothing on, excited and visibly shaken. He took one look at me still seated on “the trough” and began yelling, “Geez Shorty!! Don’t you know we just ran into a mine?? How come you’re still here?? You a dummy or somethin’?? Weren’t you scared?? Cripes!!” Still laughing like hell I answered, “Yeah I know it was a mine. No, I’m no dummy—you are running aft where the mine hit again and hell yes I was scared—That’s why I just sat where I was!” And while I was still laughing he hopped back into his clothes & shoes, cussed me out again and stormed out raving!12
Humorous incidents notwithstanding, the minesweeping process could also be deadly. The minesweeper Salute AM 294 struck a mine on 8 June 1945 and suffered nine dead and thirty-seven wounded.
The frogmen of Underwater Demolition Team 11, which arrived at Brunei Bay aboard Kline APD 120, followed on the heels of the minesweepers. The team had trained at Leyte and Morotai. They departed Morotai for Brunei Bay on 2 June 1945 and arrived on 7 June.
At 0630 on 8 June, the seventy-seven men and thirteen officers of UDT 11 disembarked from Kline and boarded the support gunboats, LCI(G)s 69 and 70 and LCS(L)s 59 and 60. Four LCP(R)s, used by the frogmen to infiltrate the beach, were taken in tow by the gunboats. At 1020 the gunboats were in position 1,000 yards off Brown Beach and began firing on shore targets. Adding to the conflagration ashore was the bombardment by Phoenix CL 46 and Conner DD 582. At 1025 a flight of B-24s appeared and dropped their ordnance on the beach area. In regard to this, Lieutenant W. H. White, CO of LCS(L) 60, commented that “A perfect example of pin-point bombing was observed about R-10 when six B-24s laid bombs exactly along the dune line covering the entire 1200 yard beach.”13 Raymond J. Ross EM 3/c, on board LCS(L) 60, later wrote:
We started for the beach along with mine sweepers over water which LCS 60 traversed time after time yesterday. To my chagrin, the sweeps picked up 8 contact mines. A little further on, they picked up more. LCIs proceeded to detonate them with rifle fire. When they went off, water and black smoke blew sky high. LCS 58, 59, 60, and two LCIs proceeded to within 1500 yards of the beach when someone shouted, “There she comes,” and the beach literally blew up in front of us.
We were now broadside to the beach and the shells were dropping ahead of us about 400 yards to starboard. The first terrific blast was U.S. B-24s, two waves of six, dropping demolition bombs. The cruisers were far behind us getting the range on the beach. Cruisers Alaska, Phoenix and one other. We received the order to open fire and strafe the beach. Concentrating first on the shore line, then working back inland. Johnson and I put out several rounds and concentrated on a building about 1000 yards inland. We started a fire and then the whole sky was filled with trees, stone, mud and wood with flares and black smoke going in every direction. We had hit an ammunition dump. The boys said it was the best show of the day.14
The UDT men boarded their landing craft and headed for shore. By 1100 they were busy charting the beaches up to the high water mark. Shortly thereafter, at 1125, a flight of RAAF Beaufighters made a run on the area and bombed the enemy’s positions. The UDT swimmers had finished their work and were headed back out to sea at 1135 when tragedy struck. Ross recalled that “two B-24s … unleashed their bomb load while the swimmers were about 50 yards from the beach. The bombs missed the target and fell in the water among the demo squad. A column of water rose like Niagara in reverse. No demo squad could be seen. Soon heads began to bob around. The Higgins boats went in and picked up the men.”15 They were picked up only forty yards off shore, while the remainder of the team made it out to 300 yards where they were picked up. One man was reported missing and it was assumed that he had been killed by the force of the bombs.16
It was most important that neither bombs nor friendly gunfire fell in the water. The most obvious reason was to avoid injury to the frogmen. However, the UDT men needed to operate in water that was relatively clear. A bomb exploding in shallow water was sure to muddy the waters for a good distance around the impact area, making accurate visual observation of the bottom exceedingly difficult.
The landing at Labuan Island took place on 10 June 1945. Six squadrons of B-24 Liberators from the 13th Air Force and two from the Royal Australian Air Force preceded the assault with high-level bombing of the beaches and areas inland. Leading the assault were the gunboats, stationed about 200 yards apart in a line. They included, from left to right, LCS(L) 58, LCI(R) 31, LCI(G) 70, LCS(L) 59, LCI(G) 69, LCI(R) 34, and LCS(L) 60. At 0730 they began their run on the beach at a speed of eight knots. Their orders were:
At about D-64.5 when 1100 yards from Brown Beach, LCS(L)s and LCI(R)s will commence firing ranging rockets. Upon hitting beach start salvoing rockets. The fire was to be distributed over a two minute period. At D-62.5 when range is 550 from beach come right and strafe with all automatic weapons. Reload rockets rapidly as we return to the line of departure.
At Z-30, upon execution of ONE flag by PC, the first wave of LVT’s will cross the line of departure, and proceed to the beach. A speed of 4 knots was to be maintained. At D-9 again salvo rocket on landing beach distributing them over a three minute period. Upon completion of firing stop all engines and lie to until the first four waves have passed. Upon their passage retire to a station on the starboard flank of boat lane waiting for call fire.17
Mortar fire was also used against the enemy with LCI(M) 359 and others lending their firepower to the assault.
The landings at White and Red Beaches on Muara Island were almost simultaneous with the landings on Labuan Island. The water depth off White Beach was quite shallow, and in their pre-landing bombardment, the gunboats could not approach it directly from the front. Fortunately, the two beaches were at right angles to one another and met at Sapo Point. Covering fire for both could be attained by the ships approaching Red Beach. This was not an ideal situation and, by the end of the pre-landing fire, it was determined that while the gunboats had covered all of Red Beach, they were only able to cover about 70 percent of White Beach with rockets and much less with gunfire. That left about 30 percent of the beach untouched. The rocket barrage was finished a full six minutes before the landing craft hit shore, making it necessary for the gunboats to cover the beaches with gunfire for an additional three minutes.
USS LCS(L)(3) 45 Serial 50, Action Report, U.S.S. LCS(L)(3) 45—Brunei Bay Operations, June 2 to June 12, 12 June 1945, Enclosure A.
The ships of TU 78.1.38, which included LCI(R)s 71, 72, LCI(G)s 23, 64, and LCS(L)s 45, 46 were involved in the 0905 assault on Red and White Beaches at Muara Island. Mortar fire was supplied by LCI(M) 431. Fortune was on the side of the troops on 10 June as they landed on Muara Island with no opposition. At 1230 LCS(L)s 45 and 46 escorted Australian troops on board LVPs into Muara Harbor to land at Brooketon Town.
Between 8 and 10 June 1945, LCI(G) 23 operated in Brunei Bay off the town of Brooketon. Her activities involved shelling and strafing various installations in the area, including telephone lines, a radar station, and various landing beaches. The chart above, taken from her action report, shows her activities during the period. U.S.S. LCI(G) 23, Action Report, U.S.S. LCI(G) 23, OBOE-SIX (Brunei Bay, Borneo) Operation, 12 June 1945, Enclosure (A).
Green Beach was under the Brunei Bluff on the northwestern side of Brunei Bay. Attacking this area in preparation for the landings were the ships of TU 78.1.37 including LCS(L)s 42, 47, 48, LCI(G)s 21, 22, 65, 68, and LCI(R)s 72, 73, 74, 230, and 338. At 0905 six of the gunboats, LCS(L)s 42, 47, LCI(G)s 65, 68, and LCI(R)s 74 and 338, were on line abreast and waiting 2,500 yards offshore. As the landing craft approached, they led them to the beaches. While larger ships bombarded the shore, the gunboats fired their automatic weapons. At 1,100 yards, the LCS(L)s and LCI(R)s let loose with their rockets. Once they had come within 500 yards of the beaches, the gunboats ceased firing and set off a red smoke flare to indicate the proximity of the landing craft to the shore. At that point the larger ships began to raise the level of their fire so that it impacted further inland. As the landing craft neared shore, the gunboats turned broadside to the beaches and raked them with automatic weapons fire. Following that, they took flank positions to the landing beach and awaited orders for fire support.
LCS(L) 45 fires on the beaches as landing craft head in to shore during the invasion of Brunei Bay, Borneo, on 10 June 1945. NARA 80 GK 5859.
The target of the last landing in Oboe VI was in the Miri-Luotong area of Sarawak just to the west of Brunei Bay. This was a very important oil-producing area. The 2/15 Battalion of the 20th Brigade, 9th Australian Division, covered by gunboats, landed with no opposition.
Oboe II, the operation to take Balikpapan, was scheduled to begin on 1 July 1945. Balikpapan was an important oil refining and shipping area. This was to be the last amphibious landing against enemy forces in the war. Okinawa was declared subdued the following day on 2 July, and the battle for the Philippines was in its last stages. Landing on the beaches at Klandasan were Australian Army troops from the 7th Division, I Australian Corps under the command of Major General E. J. Milford. The invasion force numbered about 35,000 and faced Japanese forces estimated to be around 5,400, with another 1,100 Japanese workers who might be pressed into service. Additional assistance might come from 2,400 Indonesian and 1,000 Formosan workers working behind the lines to help the Japanese in moving supplies and equipment.
The assault on Balikpapan raised several concerns. First of all, the terrain of the area was ideal for defense. There was a narrow coastal plane, and within several hundred yards of the beach the land began to rise into a series of low, wooded hills whose elevation reached 700 feet. The Japanese had placed a number of pillboxes, tunnels, and other defensive features overlooking the landing beaches. In addition, it was estimated that at least eighteen coastal defense guns overlooked the landing beaches. Bolstering the larger guns were twenty-six heavy dual-purpose guns and another seventy-eight anti-aircraft guns. These could also be used against landing craft and troops as they approached the beaches. Behind the beaches the Japanese had constructed tank traps ten to fourteen feet wide. A primary concern was that they might flood them with oil and set them on fire, making a difficult barrier for tanks and troops to cross.18 In order to prevent the Japanese from using the oil as a weapon, the oil storage tanks at Balikpapan were bombed into oblivion by Allied aircraft prior to the landings. Task Group 78.2 was assigned the task of attacking Japanese positions ashore. Included in the assault were a number of Australian Navy ships including H.M.A.S.s Arunta, Shropshire, Hobart, Manoora, Westralia, Kanimbla, Gascoyne, and Warrego. Rear Admiral A. G. Noble, Commander of Amphibious Group Eight, reported:
From a gunnery standpoint the BALIKPAPAN operation presented a most difficult problem. Enemy defenses near to and in back of the beach were numerous, strong, and well placed. Typical Japanese defenses were present: tunneled guns, concrete pillboxes, caves, and revetted C/D and D/P guns, all of which required a direct hit or a very near miss to neutralize or destroy. There were many houses, shacks and similar structures on or near the beaches, which, while not appearing heavily fortified, were nevertheless potential machine gun and small arms emplacements, and which had to be destroyed or neutralized. In addition the beaches themselves formed part of a natural amphi-theatre with high ground in the background and on the flanks. Finally, the minesweeping situation, the long approach lane, and the presence of shoals in area PHILLIES severely restricted the movement of Fire-support Ships in this area, and deprived them of their maneuverability.19
Although the ships present had their work cut out for them, other tasks needed to be performed. In the water, a job for the UDT was present:
To seaward the beaches along some fifteen miles of coast from Klandasan to Manggar were protected by a log barricade. At the Klandasan beach area this consisted of three lines of heavy wooden posts, set five feet apart, with five feet intervals between verticals. The center line was offset, and the posts were braced at the top with spiked double diagonal timbers. Apparently so placed to coincide with the surf line, the barricade was only about 10 to 15 yards off shore, and was thus within easy range of shore gunfire and Japanese snipers.20
In short, the Japanese were exceptionally well-prepared to resist any invasion force that attempted a landing. Still another problem lay just offshore. Since it was of such great strategic importance, the waters around the port had been heavily mined. In addition to mines laid by the Dutch before the war, it was suspected that the Japanese had mined the area as well. Allied forces had contributed to the plethora of mines by dropping magnetic and acoustic mines in the harbor. The task for the minesweepers was significant and placed them under the guns of the Japanese as they swept the area. Accompanying the minesweepers during their work were the gunboats which were also under attack.
Air support for the operation was supplied by several air units. The American 13th Air Force flew P-38 fighter aircraft from their base at Sanga Sanga Island in the Sulu Archipelago during minesweeping operations. The 13th Air Force and the Royal Australian Air Force flew B-24 and B-25 bombers from their bases on Morotai, Zamboanga, Tawitawi, and Palawan. These bombers were active during the entire operation bombing shore installations, and later, inland targets as the Australian Army moved forward against the enemy. As a backup, the American Navy supplied three escort carriers, Suwannee CVE 27, Chenango CVE 28, and Gilbert Islands CVE 107. On 3 July, squadrons from the carriers flew C. A. P. missions and attacked enemy positions.
Close-in fire support was rendered by the gunboats of Task Unit 78.2.8 under Commander D. H. Day on board his flagship LCI(R) 230. Included in this task unit were twenty-three support craft, including Day’s flagship. In addition to LCI(R) 230, the TU was comprised of LCI(R)s 31, 34, 73, 226, 230, 331, 337, 338, LCI(G)s 21, 22, 24, 61, 66, 67, LCS(L)s 8, 28–30, 41, 43, 44, 48, and 50. Some of the support craft would be active on invasion day, while others would cover UDT and minesweeping operations. The LCI(R)s, LCS(L)s and some of the LCI(G)s had rockets among their armament, and the LCS(L)s and LCI(G)s packed additional firepower, as all of them mounted a 3"/50 gun in addition to their 20mm and 40mm guns.
One of the important assignments for the gunboats was the covering of Underwater Demolition Teams 11 and 18 as they explored and charted the Klandasan, Manggar, and Manggar-Ketjil landing beaches and blew up obstacles to the landing craft. UDT 11 arrived at Balikpapan on board Kline APD 120 and UDT 18 on Schmidt APD 76 on 24 June 1945. This assignment appeared to be much more difficult than the reconnaissance at Tarakan and Brunei Bay. Lieutenant L. A. States, the CO of UDT 11, noted:
First intelligence indicated that the preferred and alternate beaches were heavily defended by concealed pillboxes and various other types of emplacements: that the beaches were protected by extensive and substantial man-made underwater obstacles; that these obstacles would prevent amphtracks or any other type of landing craft from reaching the beach and that the beaches, especially the preferred ones were heavily mined.21
By 1945 the Underwater Demolition Teams had perfected their techniques. They were carried to the target area on board larger ships such as the APDs, which also carried their rubber boats and LCPRs. Once the day of their operation arrived, they disembarked from the APD and went aboard a fire-support ship such as an LCS(L) or LCI(G). The fire-support ship took their boats in tow and headed in to the area of the beaches to be reconnoitered.
Equipment carried by the frogmen included a bathing suit, mask, swim fins, knife, webbed belt, mine detonators, and a plastic plate on which to record data. Neoprene wetsuits, popular with today’s divers, were not in existence at the time. The best the men could do was cover their bodies with a heavy layer of grease to protect themselves from the cold. In tropical waters cold was not a problem, but in the chilly waters off the northern islands such as Okinawa, the temperature of the water was a problem. Water temperatures at Ulithi were reported to be around 85 degrees, but at Iwo Jima only 59 degrees.22 In addition to the water temperature, other problems existed. Men might encounter sharks, stinging jellyfish, sharp coral, sea snakes and, in the more tropical areas, saltwater crocodiles.
After a period of covering gunfire, the LCPRs carrying the frogmen passed through the line of gunboats and headed to shore. At a distance of several hundred yards from shore, the LCPRs turned parallel to the beach and began to drop off swimmers while underway. A rubber boat was lashed alongside each LCPR. Swimmers went from the LCPR to the rubber boat and then rolled off the rubber boat into the water every 100 to 200 yards. “Flying Mattresses” were sometimes used. These were small rubber boats powered by electric motors. An officer would climb aboard one and head for shore. The swimmers would use them as guides so they did not get off course. The officer in the Flying Mattress made a great target, and many of the rubber boats were shot out from under them. Swimmers then headed for the beach carrying their slates and other equipment that would enable them to take notes on the conditions inshore. The depth of the water would be noted, as well as any reefs, coral heads, man-made obstructions, or mines. Once this information had been acquired, the swimmers headed back out to sea and waited in a line for the pick up. The LCPR, with the rubber boat lashed alongside, made a run past them. On board each of the rubber boats was a member of the team who held out a rope loop. As the LCPR passed by, the swimmer hooked his arm through the loop and was hauled aboard by the team member. He then climbed back up into the LCPR as the next swimmer was being picked up. The information from the first day was relayed up the chain of command. If no beach obstacles were present and no further information needed, the UDT swimmers were done. If not, they had to return for another day or two, carrying explosives inshore to dispose of obstacles. Their missions usually lasted only an hour or two but the work was strenuous. Covering the UDT at Balikpapan were the ships of TU 72.2.93 which included LCS(L)s 8, 28–30, 41, 43, 44, and 48.
Balikpapan operations. Adapted from Major General Hugh J. Casey, Chief Engineer. Office of the Chief Engineer, General Headquarters Army Forces, Pacific. Engineers in Theater Operations (Washington, DC: U.S. Government Printing Office, 1947), p. 298.
Reconnaissance of the landing beaches began at 0730 on 25 June with Underwater Demolition Teams leaving their mother ship for transit to the gunboats. UDT 11 was assigned to Green Beach at Manggar and UDT 18 to nearby Red and Yellow beaches at Klandasan. A flight of B-24s made a high level bombing run on the beach at 0730. Following that, a group of B-25s made a low level bombing and strafing attack followed by another high level attack by the B-24s. One of the B-25s was hit by enemy fire and crash-landed in the water between the gunboats and a nearby destroyer which picked up the survivors. The aircraft continued their attacks until after 0900. The gunboats attacked the shore with 3"/50 and automatic weapons fire. In the midst of this, at 0800, the LCPRs crossed the gunboat line and headed for shore.
One of the concerns of the close-in fire-support ships was a repeat of the tragedy at Iwo Jima when the Japanese mistakenly identified the LCI(G)s covering UDT operations as the beginning of the invasion. In his action report for the UDT coverage, Lieutenant J. M. Leggat, commanding officer of LCS(L) 44, noted that “LCS(L)s approached beach in an irregular manner, so as not to give the enemy impression of a landing mission.”23
Although enemy aircraft attack was always a possibility, there were not that many air attacks on the ships. However, at 2030 on 25 June five bombers, identified as Bettys, attacked the ships off Balikpapan. They managed to drop some bombs in the area but none of the ships was hit. Three of the enemy aircraft were shot down by the combined fire of the ships in the task group.24
Rear Admiral Daniel E. Barbey (right) shakes hands with General Blamey. NARA 80G 328090.
The following day, 26 June, the pattern was repeated with the swimmers entering the water at 0815. This time they brought explosives which were attached to many of the pilings that the enemy had set in the bottom to thwart landing craft. The explosives were set to go off at 1015, after the UDT men were safely back on board their boats. At the designated time the charges went off, blasting a 700 yard gap in the beach obstacles. The next day’s action resulted in an additional 800 yards being cleared of obstacles and mines. Over the course of two days, the frogmen had removed about 2,300 pilings and cleared an area approximately 1,500 yards wide on the landing beaches.25
On the morning of 28 June, at 0730, LCS(L)s 8, 28, 29, 41, 43, and 44 once again took station to support UDT Teams 11 and 18 as they operated off the beaches. At 0945 machine gun fire erupted from shore emplacements and threatened the UDT operations. The LCS(L)s strafed the beaches and shelled them with their 3"/50 guns. Return fire from heavier shore batteries, estimated to be 75mm, began to zero in on the starboard side of the support ships’ line. LCS(L) 8 reported:
At 1018, our ship was taken directly under fire by an enemy battery, and at 1020, after several near misses, we received a hit through the base of the conn on the port side resulting in shrapnel wounds to one officer and two men. Evasive action was immediately taken and return fire directed at the enemy battery with no appreciable results. However, the enemy battery ceased firing and we returned to our station. At 1045 we were again taken directly under fire by the same battery and, after some near misses, received a second hit on the starboard side below the water line, knocking out one generator, the live shell lodging in its base.26
EM 3/c John C. Black, although wounded in the attack, nevertheless managed to plug the holes in the hull, preventing further damage to the ship. A third shell passed through the flag bag without causing any casualties. About the same time, LCS(L) 41 also took hits from four shells, none of which caused serious damage. With the UDT teams recovered from their work, the gunboats headed for their anchorage at 1050. However, they soon found it under attack and had to move further out in the bay.
The initial landings at Balikpapan were scheduled for 1 July and included the Australian 18th and 21st Brigades of the I Corps. In addition, the 25th Brigade was scheduled to land on 2 July. Covering their landing was Commander Day’s Task Unit 78.2.8. On board the gunboats, general quarters sounded at 0700. About that time the heavier ships began their bombardment of the beaches. To soften up the beaches for the landing, the LCI(R)s made two rocket runs, at 0744 and again at 0846. No enemy fire was directed at them on the first run and only minimal fire on the second. The first line of landing boats hit the beaches at 0855, only a few minutes after the second rocket barrage. Return fire from the defenders was sporadic and light, much of their strength having been diminished by the pre-invasion bombardment by the larger ships and the close support craft. No casualties were incurred by the Australians during their trip to the beach. “By nightfall 1 July, 10,500 troops (two brigades), 700 vehicles and 1950 tons of supplies had been landed and 7th Division had reached its F-Day phase line.”27 As they moved inland, resistance stiffened and the troops had a dangerous enemy to face as they fought their way into the hills. Their progress was steady and, by 22 July, the enemy was finished.
Americans love to celebrate their holidays, even when at war. Admiral Noble planned a special event for 4 July 1945. Participating in the celebration were the cruisers Nashville CL 43 and Phoenix CL 46, along with the destroyers Bell DD 587, Charrette DD 581, Burns DD 588, Connor DD 582, and Philip DD 498. “Each ship fired 21 salvos; cruisers firing 21 six gun salvos and destroyers firing 21 five gun salvos into enemy troop and supply concentrations.28 An enemy ammunition dump was hit in the barrage. Its explosion eliminated a number of Japanese troops in the area and put their force into disarray.
Although the action ashore was the main event, hazards still abounded off the coast. Suicide boats had been used in the Philippines and at Okinawa, but none had been encountered at Borneo. However, on the night of 3 July, radar on LCS(L) 8 picked up a fast moving small boat heading for her. Gunners opened up with 40mm guns and, at a distance of 1,100 yards, the boat disappeared.29 LCI(G) 66 fell victim to a mine on 10 July. At 1826 she was on patrol off Balikpapan when she set off what was either a magnetic or an acoustic mine. Her engines and generators were knocked out, and the seams in her engine room and the after steering compartment were opened. She began taking on water and soon developed a list. LCS(L) 30 came to her aid and, with the addition of her Hale pump, a Johnson pump, and handy billys, the flooding was brought under control. LCS(L) 30 took her under tow and brought her alongside Creon ARL 1 which supplied additional pumps and assisted her in making emergency repairs. One officer and three men were blown over the side in the explosion but were soon rescued. No serious casualties were suffered.30
The recapture of Borneo had involved the combined forces of the Australians and Americans and had proven successful. It was time to move on for the invasion of Japan.