January 18 began one of the oddest chapters in the East Indies campaign. It also clearly showed the contempt the Japanese had for the Dutch and their ABDA allies. Upon capturing Tarakan, the Japanese found the island’s oil wells and refineries already demolished. Their next objective was the oil-rich port of Balikpapan, and the Japanese did not want a repeat of the demolitions, which would severely limit Tarakan’s production capabilities for months. So, they sent the KNIL commander at Balikpapan, Lieutenant-Colonel C. van den Hoogenband, a message threatening brutal reprisal and mass executions against the town’s populace and garrison if the pump facilities and oil refineries were not turned over to the invasion force intact.1
To carry the message, the Japanese picked two men from the captured Dutch KNIL prisoners—Captain A.H. Colijn and Captain G.L. Reinderhoff. Colijn, an army reservist, was also manager for BPM, while Reinderhoff was chief-of-staff for Tarakan’s garrison commander.2 With three Japanese interpreters and two Indonesian state police officers, the men were put aboard the Parsifal, a captured 20-ton BPM motor launch, and sent south toward Balikpapan.3
At 1630 on January 19, the launch was south of Mangkalihat in the north entrance of the Makassar Strait when X-13 and X-14 (the latter flown by Lieutenant-Commander S.H. Rosier of GVT.4) from Balikpapan sighted it. The two Dorniers circled the boat several times, obviously looking over it and the small Japanese flag flying from the stern. Then, they saw two Europeans appear and wave a Dutch flag. But the sea was too rough for a landing, so the flying boats went home after making a report.4
Down on the motor launch, the occupants were more than a little distressed. Certain the Dorniers were about to attack, Reinderhoff frantically looked through the cabin until he found a Dutch flag. He tore down the “Rising Sun” and frantically waved the Dutch flag and prayed. Just when all aboard thought the Dorniers would attack, they disappeared into the darkness of the night. All aboard spent the rest of the night drinking sake to celebrate being alive.
At 0700 the following morning, X-21 from GVT.4 made contact with Parsifal while on its morning reconnaissance flight. Again, Lieutenant-Commander Rosier was aboard. Water conditions were calm, so after thoroughly checking out the launch, X-21 landed some 500 yards off and slowly taxied in as the crew covered the launch with the machine guns and 20mm cannon. Reinderhoff was ill, so Colijn rowed them both over to X-21 with great difficulty and explained the situation.
After the two Dutchmen were taken aboard, it was all they could do to keep the crew from destroying the launch with cannon fire.5 Finally the Japanese and the Indonesian policemen were left to their own devices, and X-21 flew the men to Balikpapan, where they delivered their message.
Colonel van den Hoogenband immediately put the two men and 25 other evacuees aboard a plane to Java and issued orders to destroy the oil wells and refineries as soon as the Japanese invasion fleet appeared.6 With preparations in place, he contacted KNIL HQ on Java and arranged to have the army and BPM demolitions personnel evacuated so that the Japanese could not retaliate against them.
BPM moved quickly to evacuate a number of its personnel by sending in a Grumman G.21 “Goose,” which flew four company officials—including two women—to Bandjermasin. The MLD evacuation began the evening of the 21st when four Dorniers left Morokrembangan for the four-and-a-half-hour flight to Balikpapan. But just 30 minutes out of Soerabaja, they encountered severe weather over the Java Sea and Makassar Strait. Despite poor visibility, the X-boats could see flames from Balikpapan’s burning oil wells and refineries a full hour from the port.
Disaster struck when they reached Balikpapan, where the flying boats were to land on the Songei River and begin loading. But the weather grew worse while water conditions and visibility remained extremely poor. As a result, one plane ran low on fuel, gave up trying to land and returned to Morokrembangan empty. X-14 of GVT.4 then attempted to land but exploded in a ball of flame as it splashed down on the water. Apparently the pilot—2nd Lieutenant R.H.J. de Vries—had hit a large wave or a floating obstacle hidden in the dark water. Although Aircraft Machinist Mate J. de Lege survived, de Vries and three other crewmen were killed.7
Watching one plane turn away and another explode on the water had to be disturbing for the remaining two crews. But to their credit, they did not leave and managed to land in the rough water without serious damage. They took on 58 of the 120 militarized BPM demolition personnel at Balikpapan, along with all remaining MLD ground personnel, and flew them to Soerabaja.8 Afterwards, the surviving planes of GVT.4 remained at Morokrembangan and flew reconnaissance and air/sea rescue missions in the Java Sea until January 27.
Back on Java, there was a great deal of concern at MLD HQ regarding the secret paperwork and naval codes carried aboard X-14. The plane had crashed in shallow water, and no one was sure of its condition. During the hasty evacuation, there had been no time to ensure that the classified paperwork had been destroyed. If the Japanese discovered the plane and any paperwork intact, the entire code network of the MLD and KM would be comprised. However, it appears the Japanese failed to search the sunken hull of X-14 or the paperwork in question had been destroyed, for the codes were never compromised.
As the Dutch destroyed Balikpapan, a Japanese invasion force departed Tarakan the night of January 20–21. They originally planned to leave January 16, but the Celebes operation delayed the invasion for a week by tying up air units that were to cover the convoy. Even then, air cover was spotty; according to the famed Japanese ace Saburo Sakai, the Tainan Air Wing was not able to put more than three Zeros over the convoy at one time due to bad weather, maintenance problems and aircraft shortages.9 And since the airfield at Tarakan proved unsuitable for mass flight operations, most of the aircraft allocated to cover the invasion were forced to remain at Jolo and fly long-range missions against southern Borneo.
Nonetheless, the small number of aircraft operating from Tarakan still managed to inflict losses on the MLD. On January 21, the Dutch lost Y-51 of GVT.16 to Japanese fighters while the PBY was on a long-range reconnaissance patrol out of Tandjoeng Priok. Led by a C5M “Babs,” four Tainan Air Wing Zeros caught the seaplane on the Barito River near Bandjermasin and burned it. The crew later escaped aboard a second PBY sent to pick them up, although it too had to fight off three Japanese fighters. Her gunners claimed two fighters shot down, but the Japanese reported no losses. Y-51 was a total loss and was replaced by Y-56 several days later.
This fighter sweep, and others like it from Tarakan, was carried out in conjunction with a concentrated air campaign initiated by the 21st Air Flotilla from its new base at Menado. To support the invasions of Balikpapan and Kendari, the flotilla sent a number of air strikes against Kendari and Ambon to reduce ABDA airpower. At the same time, the unit intensified reconnaissance patrols over Western New Guinea to help ensure that the Allies were not attempting a build-up of forces in that part of the archipelago. The IJN’s 2nd Carrier Division with the heavy carriers Hiryu and Soryu further supported the operations with air strikes on Ambon.
The Balikpapan invasion force consisted of elements of the IJA’s 56th Infantry Regiment and 146th Infantry Regiment, which had just completed the conquest of Tarakan. Close escort for the convoy’s 16 transports consisted of the patrol boats P-36, P-37 and P-38, remnants of the 11th and 30th Minesweeper Divisions10 and the 31st Submarine Chaser Division. The 4th Destroyer Flotilla provided a covering force with the light cruiser Naka, which led the 2nd Destroyer Division, 1st/9th Destroyer Division and 1st/24th Destroyer Division. As at Tarakan, Sanyo Maru and Sanuki Maru provided A/S protection and air cover.
The seaplane tenders trailed the convoy by 24 hours, and their aircraft had orders not to operate too near the convoy or anywhere in the vicinity of Balikpapan prior to the invasion. This was done to avoid encountering Zeros from the Tainan Air Wing, which was flying intensive strike missions in the area and had orders to shoot down anything it encountered on the day of the invasion. While one can assume that the Tainan Air Wing pilots would have been able to distinguish their biplane counterparts, history shows that is not always the case for combatants of any nation. In any event, the Japanese elected to give the Zero pilots free reign.
ABDA reconnaissance planes quickly picked up the convoy on January 21 as it moved down the Makassar Strait; initial reports put its strength at 15 warships and 38 transports. Two days later, Dutch planes reported three groups of Japanese ships nearing Balikpapan. One of these aircraft, X-20 of GVT.7, was heavily damaged on January 20 while landing in poor visibility at Makassar. It flew to Morokrembangan for repairs, and X-35 came out of reserve to replace her.
With these reports, KM HQ stopped or rerouted shipping to Borneo ports. The Dutch destroyer Van Ghent was en route to Bandjermasin and Balikpapan with a small interisland merchant ship loaded with rice and other stores when the Japanese landed at the latter port. They proceeded on to Bandjermasin, but were then forced back to Soerabaja on the 22nd without re-supplying Balikpapan. Meanwhile, K-XVIII scuttled the Balikpapan lightship Orion with her deck gun to hamper the landings and prevent her capture by the Japanese.
Preceded by a small group of nationalist Indonesian Marechaussee, who served as pathfinders, the Japanese went ashore at Balikpapan in the early-morning hours of January 24. As one unit secured the airfield at Manggar, the Japanese’ main force moved on Balikpapan city. The port’s main defenses consisted of 1,200 KNIL regulars. Although the 6th Infantry Battalion held prepared positions, Colonel van den Hoogenband chose to withdraw into the interior of Borneo without a serious fight in order to initiate guerrilla warfare. As a result, Balikpapan was completely in the hands of the Japanese by the evening of the 25th. Aircraft of the 23rd Air Flotilla moved onto the airfield on January 28.
Meanwhile, X-29—which had just returned from Morokrembangan—rescued 32 survivors from the 2,493-ton Russian merchant ship SS Perekop. Although Japan and the Soviet Union had signed a nonaggression pact the previous year, a “Nell” from the Mihoro Air Wing sank the steamer and killed eight crewmen east of Natoena Island while on an anti-shipping patrol. X-29 rescued her remaining crew, including four wounded, and flew it to Pontianak for medical attention.
Later on the night of the 24th–25th, X-19 of GVT.4 crashed in the rice paddies near Fort Menari at Soerabaja’s Westwater entrance. The plane was returning from a night flight to Greater Masalembo Island, a tiny island in the North Java Sea. Due to bad weather, the Dornier had failed in an attempt to rescue 10 crewmen of an American LB-30 that had crashed on January 17 following a raid on Menado.11 In the dark, the exhausted pilot put the Dornier down in a rice paddy he thought was the channel to Morokrembangan. The plane broke up on impact, killing both pilots.12 GVT.4 disbanded two days later, and its one remaining Dornier, X-24, went into the reserve pool.
By now, exhaustion was common among all MLD flight crews. Many, such as the pilot of X-19, were flying 15 to 18 hours a day for 10 or more days at a time. Although the High Command attempted to rotate squadrons to Java for rest, the Japanese advance severely hampered these efforts. In addition, many of the airmen had to help service their planes or plan upcoming missions. Frequent moves to new bases, punctuated by air raids, made life for MLD airmen even more difficult.
As the Balikpapan force left Tarakan on January 21, a convoy of six transports simultaneously sailed from Menado for the port of Kendari on the southeast coast of Celebes. It carried the 1st Sasebo Special Naval Landing Force, which had secured Menado and Kema two weeks earlier. Escorted by the auxiliary vessels of Rear-Admiral Kubo’s 1st Base Force, the light cruiser Nagara, the 15th and 16th Destroyer Divisions and the seaplane carriers Chitose and Mizuho, the convoy moved through the Peleng Strait and appeared off Staring Bay at 0200 on January 24.
All Allied shipping had cleared the bay except for the PatWing 10 tender Childs. She had arrived during the night of January 22–23 with 30,000 gallons of aviation fuel for the Kendari II airstrip, which B-17s from Java used as a staging base for attacks on the Southern Philippines. As other ships cleared the harbor, Childs’ crew worked feverishly to unload its volatile cargo. The crew became particularly motivated after an enemy observation plane flew over the harbor.
The operation was completed just before dawn, and Childs got underway. As she entered the South Channel, lookouts sighted four Japanese destroyers on an intercept course. At 0532 one of them challenged Childs with the signal “A8Y … A8Y … A8Y.” Signalman Rod Nordfelt did not know what it meant, so for lack of a better response, he returned the signal, which briefly confused the Japanese.13 But at 0535 the destroyer challenged again.
Fortunately, a rain squall blew over Childs, hiding her from the approaching destroyers. Lieutenant-Commander J.L. Pratt took advantage of the brief cover by changing course and running down the narrow channel at full speed in near zero visibility. So extreme was the need for speed that boiler room engineers locked down the safety valves in order to get more steam pressure.
As she cleared the south channel, lookouts reported landing craft entering the North Channel. Their attention was quickly diverted by the four destroyers that now pursued. However, they apparently thought Childs was a harmless merchant vessel incapable of hindering the landings, for they quickly turned away to protect the anchorage.
Thirty-five minutes later, three fighters undoubtedly called in by the destroyers came in low for a better look. They quickly discovered Childs was not defenseless when heavy machine gun fire drove them off. Five minutes later they returned, but AA fire drove them off for good with the leader trailing smoke.
At 1415, a single-engine cruiser floatplane appeared and challenged the seaplane tender with the signal “A8Y.” Childs’ signalman again responded with an identical signal, but the pilot saw through his deception and immediately dropped two bombs at 1422. Both missed, and AA fire quickly drove off the plane. Pratt was now certain a cruiser was near and immediately turned southeast at full speed and made Soerabaja two days later without problems.
With fewer than 400 troops supported by four armored cars and a handful of AA guns, the local KNIL commander could put up little resistance.14 His task was made even more difficult by the fact that many of his Indonesian troops had already deserted in the face of heavy air attacks that preceded the actual invasion. As a result, the Japanese were able to take possession of Kendari II by the evening of the 24th with only two men wounded. Although Dutch army and air force personnel managed to destroy most of the air field’s installations and fuel supplies, 1st Base Force engineers had the runway operational within 24 hours. Meanwhile, Chitose and Mizuho provided air cover until the 21st Air Flotilla arrived on January 25.
With the loss of Kendari, MLD operations in the northern East Indies could now only be carried out at great peril. And not only did the Japanese now control most of the air over the East Indies, but their bombers also could now hit Morokrembangan, Soerabaja and other airfields on Java at will. Beginning in the first week of February, this would have a profound impact on the MLD’s operations.
Despite the dramatically increased Japanese air presence over Borneo and Celebes following the loss of Balikpapan and Kendari, MLD and USN planes continued to fly regular reconnaissance missions up the Makassar Strait to Balikpapan, Kendari and points along the Minahassa Peninsula. Soon after the fall of Balikpapan, one of these aircraft reported the presence of a large convoy assembling in the port. Initial reconnaissance reports put its strength at 20 transports with an escort of three light cruisers and 10 destroyers. The ABDA High Command correctly assumed that this concentration was an invasion force destined for either Makassar on southwest Celebes or Bandjermasin on the east coast of Borneo.
Initially, this convoy was to move south and seize the airfield at Bandjermasin. However, after strong ABDA naval and air counterattacks at Balikpapan, the Japanese felt overexposed and believed that they did not have adequate naval resources to effectively cover the operation. As a result, they changed their plans and went with a two-pronged attack using fewer naval resources, with the primary focus being on land movement. In the meantime, the transports withdrew to Palau to refuel.
On January 27 units of the 146th Infantry Regiment sailed from Balikpapan aboard a small force of barges. They had orders to skirt the Borneo coast and then advance overland on Bandjermasin, taking a number of smaller port cities in the process in order to secure their flanks. Three days later, a battalion from the 146th Infantry Regiment also set out from Balikpapan and moved overland toward Bandjermasin. The two columns linked up near Ulin Airfield on February 10. The town and airfield were both in Japanese hands by that evening, but the Dutch forces had badly damaged the airfield before being withdrawn to Java by air. As a result, the runway remained out of commission until February 25.
With Kendari II in their hands, the Japanese felt secure in moving against Ambon, which both they and the Dutch regarded as a key outpost in the Allied defense of the Eastern East Indies. While the KM regarded Ambon as little more than a staging base for its submarines, for the MLD it was the headquarters for their operations in that part of the archipelago. At the same time, MVK Halong served as a major secondary base for Dutch and American seaplanes scouting Japanese movements. For the Japanese, capturing Ambon would eliminate a major Allied air base, add to their sphere of air superiority and further secure their flank from Allied counterattack during the invasion of Java. At the same time, it would ensure the isolation of Dutch forces in New Guinea from supplies, reinforcements or evacuation.
A number of PatWing 10 PBY and J2F utility aircraft had been based at Halong since early January. However, life at the partially completed base was not easy. While Dutch personnel occupied the complex’s completed barracks, the American crews and RAAF personnel from nearby Laha Airfield were assigned to Halong’s unfinished barracks and mess halls.
These barracks had no beds and consisted of concrete slabs and walls without windows or running water. The sudden influx of allied personnel had also overwhelmed the island’s primitive supply chain, thus ensuring a near constant shortage of food, which was generally bad to begin with. And finally, although the Australians and Americans got on well, tension between Dutch and PatWing 10 personnel constantly simmered just far enough below the surface to negatively influence low-level allied cooperation at a time when it was critically needed.15
Despite primitive living quarters for the aircrews at Halong, the harbor itself was excellent for Allied seaplanes. Ambon’s inner harbor was almost completely enclosed by hills reaching some 800 feet in altitude. The harbor’s narrow entrance was securely blocked with a log boom that was protected by an extensive barrage of 70 mines both inside and outside the harbor.
The Japanese had pounded Ambon from the air since the first week of January in preparation for its upcoming invasion. Their first air raid on the island came on January 7 and concentrated on MVK Halong and Laha Airfield, from which three Dutch Buffalo fighters and a squadron of Hudson bombers from 13 Squadron (RAAF) operated.16 Together with a handful of Dutch AA batteries, the Buffalos represented the island’s entire air defense.17 Twelve USAAF P-40s were also slated to operate off the island with the bombers, but they never arrived.
In the face of such feeble defenses, the Japanese were able to operate over the island almost at will. In their first raid, the Japanese completely surprised the base and caught the Dutch fighters on the ground. Their bombs damaged one Buffalo and obliterated two of the Australian Hudsons while also damaging the airfield facilities. The bombers also targeted the GM vessel Valk, which tended to the aircraft of GVT.17 in Halong harbor. Although Valk was undamaged in this raid, the KM high command on Java ordered her captain to leave the area soon afterwards.
On January 14, the Japanese dramatically increased the weight of their attacks on Sorong. They wanted to ensure that no Dutch planes would interfere with the invasion of Ambon. Sorong, which had been under regular attack from enemy flying boats operating from Palau and Davao since mid-December, was soon completely isolated and untenable. Within days, Captain Bozuwa ordered the ordnance and fuel stocks destroyed and the base permanently abandoned.
A second raid on Ambon followed on January 15 when 27 “Betty” bombers from the Kanoya Air Wing again raided Ambon. In a repeat of the initial air attack, nine escorting fighters from the 3rd Fighter Wing quickly disposed of the two remaining Dutch fighters, allowing the bombers to work unmolested from the air. Again concentrating on the airfield and naval air station, they destroyed another 13 Squadron Hudson, although seven others were undamaged. Bombs also severely damaged the naval air station before the raiders turned for home.
Meanwhile, three fighters provided cover while six Zeros came down to strafe the air station, where they found two PatWing 10 PBYs landing in the harbor. Completely unaware that Japanese aircraft were in the area, 22-P-7 was hit almost immediately, and the starboard wing exploded in flames as shells penetrated its fuel tank.18 However, the pilot managed to put his PBY down without further damage, and the fire was extinguished. 22-P-8 was also forced down in flames shortly afterward and beached, where the PBY became a burned-out wreck. The fighters then turned their attention to 22-P-10, which was quickly destroyed at its mooring.
After the Zeros departed, Dutch ground crews pulled 22-P-7 into Halong’s only surviving hangar for repairs. They found that although all the fabric on the starboard wing had been burned away and the hull was pocked with shrapnel hits, the plane seemed structurally sound. However, because of the island’s weak air defenses, all remaining USN aircraft were ordered to withdraw later that day, and the damaged PBY was abandoned in the hangar when the remaining PatWing 10 personnel and aircraft flew out early the following morning.
Their departure was timely, as four 3rd Air Wing Zeros guided by a C5M “Babs” scout plane returned to Halong the following day. Although pickings were scarce with the withdrawal of PatWing 10, they still claimed to have destroyed a twin-engine flying boat. However, since there were no American planes left on the base and no Dutch aircraft were lost that day, the claim was likely a repeat claim on 22-P-7, which survived this attack as well.
Following this attack, GVT.17 also evacuated Ambon for Morokrembangan on the 16th. A lack of AA defenses and no fighter presence made it impossible for the squadron to continue operations from the base. The squadron had also been stationed at Halong since before the start of war, and its crews needed rest after six weeks of uninterrupted operations.19 In addition, with the loss of Y-58 and the heavy damage suffered by Y-60 over Kema, GVT.17 was down to only one effective aircraft. Y-67 replaced Y-58 from the reserve pool upon their return to Java.
On the 24th, 18 “Nells” from the 23rd Naval Air Flotilla again hit Ambon, all but demolishing what was left of Halong. The lone remaining hangar, most repair shops, fuel dumps and barracks were destroyed. The still unrepaired 22-P-7 was finally destroyed for good when the hangar was leveled. At the same time, Zeros burned two PatWing 10 PBYs (22-P-5 and 22-P-10) on the water. Later that day, more than 50 aircraft from the 2nd Carrier Squadron (Hiryu and Soryu) added to the destruction.
A fourth American PBY operating from Ambon that day survived because it was on patrol. 22-P-4 evacuated Ambon for good the following day, carrying 36 evacuees that included the two destroyed PBYs’ aircrews and a number of MLD ground personnel. As they departed, Japanese carrier planes again pounded Halong. Two more PatWing 10 PBYs flew in from Java on the 27th to evacuate 25 more Dutch personnel and civilians, including Captain Hekking and his staff.
The MLD ground personnel who had remained behind now worked to rig the seaplane ramp and few remaining repair shops, ordnance dumps and fuel stocks for demolition and ensure that they were successfully destroyed before the island fell. Just before the Japanese landed, a small reserve stock of aviation fuel that had been saved for emergency flight operations was contaminated with turpentine, and the fuses of all remaining ordnance were thrown into the sea. Their last act was to burn the KM’s archives and other records.
At the same time, KM shore personnel destroyed the submarine base and fuel oil stocks and burned the port’s warehouses. All of these men were supposed to have been evacuated once the demolitions were completed. But due to a breakdown somewhere in the KM’s overloaded communications network, their evacuation was botched, and the Japanese captured most of them. However, three of the MLD men were evacuated at the last minute aboard an Australian Short Sunderland flying boat that flew in to help bring out RAAF personnel.
Even after the Dutch and Americans had evacuated Halong, the Hudsons of 13 Squadron continued to operate from Laha Airfield. This was because the Australians saw Ambon as a critical link in the defense of the NEI; if the NEI fell, Australia would be open to attack from the Japanese. For this reason, the Hudsons remained at Ambon and continued to fly reconnaissance and strike missions in the face of ferocious air attacks. But by January 28, the raids were too severe for even the Australians, and 13 Squadron withdrew its aircraft as well.
The Ambon invasion force sailed in two groups. The first five transports sailed from Davao on January 27 with elements of the 56th Infantry Regiment. The destroyers Arashio and Michisio of the 8th Destroyer Division and the sub chasers Ch.1 and Ch.2 escorted them. The following day six transports carrying the Kure Special Naval Landing Force left Menado escorted by the 2nd Destroyer Flotilla, and the two convoys joined on January 29. They received air cover A/S support from Chitose and Mizuho, which were screened by the 1st/15th Destroyer Division, 21st Minesweeper Division and two patrol boats. Two heavy cruisers and two destroyers covered the operation from the Celebes Sea.
The landing itself started early on the morning of January 31. Naval ground troops began moving ashore before dawn and were quickly followed by army troops. Despite fierce resistance from the combined Dutch/Australian garrison, Ambon fell on February 4, depriving the MLD of its most important forward base. The loss of Halong was critical, as allied reconnaissance aircraft damaged while operating in the northern NEI would now have to fly all the way to Java.
Despite the pending loss of key seaplane facilities at Ambon and Sorong, the MLD continued to strike back as best it could. On the 16th X-29 of GVT.6 strafed the runway at Kuching. Returning to base, the pilot reported three merchant ships of about 2,000 tons each in the harbor. Two days later, X-28 and X-29 attacked the merchant ships but hit nothing. In the process, X-29 suffered damage that forced its return to Morokrembangan for repairs; she rejoined the squadron several days later.
They returned with X-31 on the 19th, concentrating on the airfield and two large and two small merchant ships in the harbor. However, a heavy rainstorm limited visibility and forced the aircrews to bomb and strafe from high altitude. As a result, the planes achieved poor results despite encountering only light AA fire.
GVT.6 returned to Kuching later that afternoon, and all three seaplanes circled the airfield for an hour attacking targets of opportunity. Despite heavy return fire from Japanese AA,20 the Dorniers laid 18 bombs on the airfield but inflicted only light damage, although one reportedly destroyed a fighter as it was taking off to intercept the Dutch planes. Another bomb hit what appeared to be an ammunition dump, causing a huge blast as the squadron turned for home.
The squadron returned to Kuching on the 22nd. However, despite circling the city for several hours, the planes encountered bad weather and couldn’t drop more than eight 100-pound bombs. In this attack X-29 hit the quays and left them in flames. With this, GVT.6 called off its assault on Kuching. Spies for the Netherlands Interior Service21 later reported that the three-day campaign had badly cratered the runway and burned several planes and that a single 500-pound bomb dropped on the airfield had killed some 400 Japanese on the runway.
Still, by late January, the main force of the MLD had been driven back to Java. Only a few squadrons of Dutch planes still flew in the outer reaches of the East Indies. It was only a matter of time before they too were pushed back to Morokrembangan as the Japanese began their final push to break Dutch resistance. The tenders also followed their seaplanes back to Soerabaja after being constantly targeted by Japanese bombers. The last tender to “come in out of the cold” was Poolster, which arrived at the ME from Pontianak on January 13.
The IJN now attempted to clear all remaining ABDA airpower from the Eastern East Indies. The first indication of their presence was a reconnaissance plane over Koepang on January 25. The next morning, the 3rd Air Wing sent six A6M2s guided by a C5M “Babs” to hit Timor. Arriving over Koepang Harbor, three of the fighters stumbled across a KNILM Ga.21 “Goose” amphibian that had just taken off. Completely surprised by the Zeros, the unarmed “Goose” almost immediately dove into a small ravine, killing all aboard, including the pilot, wireless operator, flight mechanic and two passengers.22 The fighters then proceeded to work over the dockyard installations.
The remaining “Zekes” proceeded to Penfoi Airfield, where they found a number of Allied planes dispersed in uncamouflaged aircraft pens. In the absence of AA fire, they first burned a loaded civilian Dragon Rapide on the runway, killing its female pilot and five passengers. They then proceeded to strafe and burn a second civilian aircraft and a stranded American P-40E Kittyhawk belonging to the 17th Pursuit Squadron. With all Allied aircraft destroyed, the Japanese turned their attention to the hangars, barracks and radio station.23
Although not a military aircraft, the Grumman G.21a “Goose” was extensively employed throughout the NEI by civilian, corporate and religious organizations (photograph courtesy of San Diego Aerospace Museum).
Two fighters then wandered out over the Soemba Strait, where they randomly encountered a DC-2 attached to 36 Squadron (RAAF). The transport was en route to Penfoei from Soerabaja when the Japanese attacked. In a brief, one-sided fight, the Douglas was also soon forced into the sea, where it sank. The four crewmen then spent 30 hours floating in shark-infested waters before washing ashore on Soemba Island, where local Indonesians summoned Dutch authorities to care for them.24
Meanwhile, Y-59 of GVT.17, which had been pulled back to Morokrembangan after the fall of Menado, was heavily damaged on the 24th when two Japanese fighters caught her over the Java Sea while escorting the damaged Dutch submarine K-XVIII to the ME. The damage was so extensive that the Catalina had to immediately return to the naval air station for comprehensive repairs.
K-XVIII had been stationed off Balikpapan to interdict Japanese landings. Although she failed in an attack on Naka, she succeeded in sinking the 6,988-ton transport Tsuruga Maru. However, a counter–depth charge attack by the subchaser Ch. 12 screen caused severe damage to her electric engines. As a result, she could not travel while submerged and had to make the entire distance from Balikpapan to the ME on the surface. For most of her trip, MLD seaplanes were the only aircraft with sufficient range to provide air cover. After Y-59 was damaged, three USAAF B-17s and later P-40s from Java escorted the submarine.
On the 26th, X-29 of GVT.6 retaliated by attacking a small Japanese schooner on Borneo’s Sarawak coast between Tandjoeng Api and Kuching. The Dornier was on routine patrol when the crew sighted a schooner of about 300-tons laden with troops and dove to attack. In a bitter fight, the X-boat suffered heavy damage from small-arms fire but left the ship in flames and broke for home. In return, Machinist Mate T. Veldman was killed and another crewman wounded in this action. X-29 flew to Morokrembangan for extensive repairs on the 28th.
This invasion force was sighted at 2000 on the night of the 27th by a Dutch coast watcher on the west coast of Borneo. Although he signaled KM HQ that a Japanese force of about 20 ships was rounding Tandjoeng Datoe on a southerly course, Admiral Helfrich was annoyed that the watcher had included no ship descriptions.25 GVT.6 was ordered to fly a night reconnaissance mission but could not locate the convoy. The planes went out again at first light and discovered the Japanese force in the Sambas River, just south of Pemangkat on Borneo’s southwest coast. However, the “fleet” contained no large ships, but rather consisted of 10 small native craft and six motorboats ferrying some 500 troops.
The MLD planes attacked with 100-pound bombs and strafing with little effect. Based on GVT.6 reports, the Dutch light cruiser Java was dispatched from convoy duty in the Soenda Strait to intercept. Tromp, screened by the destroyers Piet Hein and Banckert, was also ordered to stand off and engage the Japanese main force if it was sighted. But because Java had to wait until the covering force got into position, she reached Pamangkat several hours too late and missed the Japanese force; the four vessels then withdrew to avoid air attack. The Japanese had landed at 0700 on January 28 and quickly moved to occupy the port city of Sambas and its MLD base. They then moved south and occupied Mampawang, Pontianak and the ML airfield at Sinkawang.
In response to the MLD raids on its convoy at Pemangkat and Sinkawang, five G3M “Nells” from the Mihoro Air Wing struck the GVT.6 auxiliary base at Tajan. With most of its supplies destroyed in this attack, the squadron withdrew to Ketapang on the southwest coast of Borneo. In the process, 120 drums of aviation fuel, 50 cases of oil and a large supply of bombs were destroyed, as they could not be taken out. The aircraft dock and buoys were also scuttled to prevent their capture. The squadron flew reconnaissance missions along the Borneo coast from Ketapang until the 30th. When Japanese troops approached the base, X-28 and X-31 withdrew to Morokrembangan, where they joined X-29.
As the Dutch struggled to maintain a foothold in the NEI, the British seaplanes of 205 Squadron were being forced out of Malaya by intense Japanese air raids. Having lost six PBYs since the first week of December, the squadron evacuated its last five operational aircraft from Seletar on January 29. Setting up operations at Tanjoeng Priok, FV-N, FV-R, FV-U/Y-53, FV-V and FV-W/Y-54 came under the command of Captain Bozuwa’s REC-GROUP and were detailed to fly reconnaissance missions over the Java Sea and South China Sea.
Shortly after their departure, the tender Tung Song was ordered from Seletar to the port of Oosthaven on Southern Sumatra. There, she set up a temporary base to help extend the range of the squadron’s Catalinas. In her absence the American seaplane tender Holland provided support for 205 Squadron at Tandjoeng Priok.
On January 31 the MLD high command received reports of a Japanese convoy in the area of Boeton Island, some 50 to 75 miles south of Kendari. In response, GVT.3(NEW) was ordered to mount a night attack from Morokrembangan. Although the squadron arrived at Boeton in good order, it was unable to locate the Japanese and spent a good deal of time searching for the elusive convoy. It eventually sighted a lone Japanese ship near Kendari, which it attacked with unknown results. The squadron had little time to spend over the target as all of the PBYs were running low on fuel and were forced to turn for home. This mission closed out the month of January.26
By the end of January, the Dutch retained a tenuous foothold at only Bandjermasin on Borneo’s east coast and Makassar on the southern tip of Celebes. From their newly acquired bases at Balikpapan, Pontianak, Sinkawang (a former KNIL airfield in the interior of Borneo) and Kendari, the Japanese could now hit virtually every target on Java and Southern Sumatra. The only harbor of significance that lay outside their reach was Tjilatjap on the south coast of Java. At the same time, Kendari II and a captured secondary airstrip on the island of Ceram allowed regular attacks on Timor, which also lay on the Japanese list of targets. Its capture would cut the Allied supply line to Java and further isolate Allied forces on the island.