Rabaul 1943–44

by Mark Lardas

  Opening the siege: October 12–November 4, 1943

  The Fifth Air Force returned to Rabaul in force on October 12. Kenney wanted to start earlier, but bad weather intervened. Photo-recon missions needed for pre-mission targeting kept getting scrubbed by clouds. Not until October 6 did recon aircraft, modified P-38 Lightnings, return with good photos. Additional flights were made on October 9, giving planners the latest information on ship and aircraft locations. The first mission indicated that Rabaul held only 184 aircraft: 87 twin-engine bombers, 37 single-engine bombers and 60 fighters. The later flight revealed the count had increased to 270. Aircraft to support Operation RO had arrived.

  The totals did not affect Kenney’s dispositions. He planned a maximum effort for his first strike. He sent everything he had: 115 B-25s, 87 B-24s, and 12 Bristol Beaufighters, escorted by 125 P-38s, a total of 339 aircraft. Including the weather and photo-recon aircraft sent out, over 350 Allied aircraft participated.

  The B-25s left Dobodura at sunrise, and headed to Kiriwina, where they picked up a fighter escort, 78 P-38s. By the time the last of the B-25s had taken off, visibility at the airfield had dropped to zero due to dust. The Australian Beaufighters had to delay their departure until the dust settled. They finally became airborne at 0815hrs, but the late departure caused them to miss their fighter escort. The B-25s were assigned Vunakanau and Rapopo as targets. Five squadrons were to hit Vunakanau and three Rapopo. The Beaufighters were to strike Tobera.

  The Fifth Air Force opened its offensive against Rabaul with attacks on three airfields. This photo shows B-25s attacking Vunakanau, using parachute bombs. Three G4M bombers in revetments are on the field. The picture was taken from an aft-pointing strike camera. (USAAF)

  While the B-25s were leaving Dobodura, B-24s from the 43rd and 90th Bombardment Groups were taking off from Port Moresby. With 6,000lb of bombs and a full load of gasoline, these aircraft were heavily laden. To allow for a fuel-conserving gradual climb to altitude, the heavies followed a path south around the tip of New Guinea, before heading east. As they crossed the Solomon Sea, they picked up an escort of 47 Lightnings from Kiriwina. Due to their longer flight path, they would arrive nearly two hours after the B-25s.

  The medium bombers and their fighter escort flew over the Solomon Sea south of New Britain at virtually wave-top altitudes to stay under Japanese radar. They flew well south of Gasmata to avoid patrolling aircraft, turning north when they reached St George’s Channel. They turned west at Wide Bay, using the mouth of the Warango River as a navigation point.

  Even minutes from its targets, the Allied airstrike was still undetected. The Japanese had been lulled into complacency by the long Allied absence. Focused on preparations for Operation RO they had neglected the threat of an Allied attack. But they knew what a Fifth Air Force raid could do, for Kenney’s boys had wiped out Wewak in August. The aircraft losses were so bad that in September most Imperial Army Air Force aircraft at Rabaul were transferred to Wewak as replacements.

  First strike by the Fifth Air Force

  October 12, 1943

  Axis

  Allied

  Airfield

  EVENTS

  1.The 46 B-25s of the 3rd Bombardment Group ingress at between 500 and 1,000ft, heading for Rapopo Airfield, an IJA bomber base. As they reach the Gazelle Peninsula coastline, they descend to below 100ft.

  2.The 67 B-25s of the 38th and 345th Bombardment Groups head for Vunakanau, a combined IJA and IJN airfield used for bombers and fighters. Crossing the coastline, they drop to below 100ft.

  3.0855hrs: the B-25s of 3rd Bombardment Group strike Rapopo Airfield. Zeros attempting to take off from Rapopo are shot down. As the B-25s egress, they climb to 1,000–2,000ft.

  4.0900hrs: the B-25s of the 38th and 345th Bombardment Groups hit Vunakanau. Once again, surprise is total; the B-25s shoot down any Zeros attempting to get airborne. The B-25s climb to 1,000–2,000ft on their egress.

  5.Japanese interception fighters manage to take off from Lakunai Airfield and vainly pursue the B-25s of the 38th and 345th Bombardment Groups and their fighter cover.

  6.1055hrs: 12 Beaufighters of RAAF No. 30 Squadron conduct a low-level raid on Tobera, another IJN airfield and primarily a fighter base. The Japanese fighters there are caught on the ground. The Beaufighters climb to 1,000–2,000ft as they egress.

  7.1205hrs: 62 B-24s (of the 87 that started the mission) of the 43rd and 90th Bombardment Groups conduct a high-level raid (21,000–23,000ft) against shipping in Simpson Harbor. The B-24s are escorted by P-38 fighters.

  USAAF AND RAAF

  1.3rd Bombardment Group

  2.38th and 345th Bombardment Groups

  3.No. 30 Squadron, RAAF

  4.43rd and 90th Bombardment Groups(with 100+ P-38s, fighter cover)

  JAPANESE

  A.Japanese A6M “Zeke” fighters (from Lakunai Airfield)

  25mm AA guns (effective range c.6000ft)

  75mm AA guns (effective range c.20,000ft)

  127 mm AA guns (effective range c.26,000ft)

  25 & 75mm AA guns

  25 & 127mm AA guns

  25, 75mm & 127mm AA guns

  On November 2, 1943 the Fifth Air Force struck Simpson Harbor with 72 B-25s. One squadron armed with para-frag bombs strikes docks and harbor warehouses, damaging barges along the docks. (USAAF)

  Once over land, the B-25s split into two sections. The three squadrons of the 3rd Bomb Group turned north to Rapopo. The remaining five squadrons, from the 38th and 345th Bomb Groups, turned west to Vunakanau.

  Rapopo, closer to Wide Bay, was hit first. Flying line-abreast at treetop level each squadron swept across Rapopo. Flying south to north, along the runway, the B-25s strafed the airfield with their eight .50-caliber nose guns. When over the airfield they dropped bundles of para-fragmentation bombs, 50–60 per aircraft. The parachutes slowed the descent long enough for the B-25s to clear the area before the bombs exploded. Three waves struck Rapopo, each squadron spaced 60–90 seconds apart. No sooner did the Japanese get up after one wave attacked than the next one came through.

  Ten minutes later, the scene was repeated at Vunakanau. Instead of three waves, five waves hit Vunakanau. It was a larger airfield, so targets remained when the fifth squadron flew over, seven minutes after the first.

  Surprise at both airfields was total. The first warning of trouble at Rapopo was the attacking Americans firing. Antiaircraft guns were covered with canvas when the first wave hit. Personnel were in the open, aircraft were on the ground. Even with ten minutes’ warning, Vunakanau was little better prepared, with guns unmanned during the first strike. Although the guns were brought into action by the final waves, the gunfire was inaccurate and disorganized. Five Japanese fighters were in the air when the attack started, and were joined by others from Lakunai as the attack progressed, but only shot down one bomber.

  Once they had finished their attacks, the B-25s headed to open water. The Rapopo strike force continued north until it reached St George’s Channel, and followed that east and south around Cape Gazelle. The squadrons which had hit Vunakanau turned right, and flew south of Vulcan Crater and over Keravia Bay to reach St George’s Channel.

  Then, just before 1100hrs, the Beaufighters arrived. Tobera was smaller than the other two airfields, and inland. But the Japanese were alert, and the Australian aircraft were intercepted by 19 Zeroes over the airfield. The Beaufighters did less damage than the B-25s due both to their fewer numbers and to the smaller target.

  Finally, at noon, the B-24s arrived. By now they were at altitude, 21,000–23,000ft high. They attacked the town of Rabaul and shipping in Simpson Harbor. By this time the Japanese were thoroughly alert and looking for trouble. Thirty-four fighters, probably launched from the untouched Lakunai fighter strip, met the Liberators. The escorting P-38s were largely ineffective, and several B-24s were damaged by attacking Japanese. Three failed to return to base, one ditching near Kiriwina.

  The attack was a resounding success for
the Fifth Air Force, although Kenney’s claims were extravagant: over 150 aircraft destroyed on the ground, 26 Japanese fighters shot down, and three large transports, 43 small merchant ships, and 70 harbor craft sunk, with many more damaged. The actual results were less spectacular, but still impressive. Perhaps 60 aircraft were destroyed or badly damaged on the ground. Five fighters were shot down, including one shot down by a B-25 as it took off at Vunakanau. Ground personnel at Vunakanau and Rapopo took heavy casualties. Two fuel dumps were destroyed, and airfield buildings damaged. Seven warships had minor damage, and six cargo ships sunk, including an 8,500-ton naval auxiliary, two 550-ton sea trucks, and three smaller vessels. In exchange, the Allies lost five aircraft: three B-24s, one B-25, and one Beaufighter.

  Kenney followed up the attack almost immediately. Twelve RAAF Beaufort torpedo bombers conducted a night raid against shipping in Simpson Harbor. Most failed to reach their target, with only two torpedoes launched and no hits. All 12 returned safely.

  A larger follow-up was launched on October 13. Maintenance crews turned around virtually all aircraft overnight. In the morning, 70 B-24s left Port Moresby retracing the previous day’s path, rendezvousing with 100 P-38s north of Kiriwina. Their target that day was Rabaul city, and its warehouses. The aircraft never reached their destination. The formation flew into a storm front halfway to New Britain. Visibility dropped to zero, and B-24s began icing. The mission was aborted and the planes returned home, the weather proving as deadly as the Japanese. One B-24 and three P-38s disappeared in the clouds. Weather prevented any further attacks on Rabaul for a week.

  The storm fronts were south of New Britain, but the Japanese flew north of New Britain attacking New Guinea from Rabaul. The Japanese retaliated for the October 12 strike three days later. On October 15 a strike was sent against shipping in Oro Bay off New Guinea to cut supplies to Dobodura. This maximum Japanese effort consisted of 15 Aichi D3A (Val) dive bombers and 39 Zero fighters. Intercepted by P-38s and P-40s, the Japanese aircraft were shredded. Only one D3A returned to Rabaul and five Zeroes were shot down. Damage to shipping was trivial.

  A follow-up attack two days later proved equally unrewarding. The Japanese sent 56 Zeroes on a fighter sweep to Dobodura. A slightly smaller number of US fighters met it. Eight Zeroes were splashed. The United States lost four P-38s and one P-40. It was the last time Japanese aircraft from Rabaul struck at Allied bases in New Guinea. The initiative was passing to the United States and its Anzac partners.

  Since weather prevented it from raiding Rabaul following its October 13 strike, the Fifth Air Force instead visited Wewak. On October 18, good weather was expected and another major strike was launched. Kenney sent 77 B-24s, 54 B-25s, and nearly 100 P-38s to hit the airfields. The heavies were after Lakunai and Vunakanau, with the B-25s to strafe Rapopo and Tobera. The mission hit a stationary front south of New Britain. The Liberators and Lightnings turned back, but the leader of the Mitchells pressed on, despite the abort call. Three B-25 squadrons hit Rapopo, one hit Tobera, while one strafed shipping in Blanche Bay. But after hitting their targets, the unescorted bombers were jumped by 40 Japanese fighters. Two ships were damaged, and 11 Japanese fighters destroyed at the cost of three B-25s lost and six badly damaged.

  Other B-25s hit ships in the harbor with 1,000lb bombs. A bomb falls aft of a transport during the attack on Simpson Harbor. Note the ship listing directly behind the attacked freighter. (USNHHC)

  The weather finally cleared on October 23, and daily raids began. October 23 saw 57 B-24s and 100 P-38s sent to bomb Lakunai and Vunakanau. These were clouded over; the bombers hit Rapopo instead. On October 24, 64 B-25s escorted by 54 P-38s strafed Vunakanau, Rapopo, and Tobera. Sixty-one B-24s with 50 escorting P-38s conducted high-level bombing of Vunakanau and Lakunai on October 25. On all three days, swarms of Japanese fighters – at least 40 Zeroes each day – met each raid. Earlier Japanese losses were replaced from reinforcements sent to support Operation RO. Fifth Air Force losses for all three days totaled one B-24, two B-25s, and two P-38s. The Japanese had 15 fighters shot down and six badly damaged in air-to-air combat, with over 60 aircraft destroyed or damaged on the ground. The Fifth Air Force believed it had done much better. Kenney claimed 86 aircraft destroyed on the ground and 100 shot down.

  Then the weather closed things down again. A front stalled south of New Britain, providing a storm wall blocking raids from New Guinea, and giving the Japanese at Rabaul a four-day rest from the Fifth Air Force. They needed it. Their reconnaissance revealed that the United States was on the move in the Solomons. Halsey was preparing to invade Bougainville, and convoys were forming. The Japanese had been forced out of all their Solomon Islands airfields. The only opposition to this new Allied thrust had to come from Rabaul.

  Admiral Kusaka called to Truk for help. By this time he had only ten dive bombers and 36 twin-engine rikko operational, too few to oppose the invasion. The Combined Fleet responded by sending everything available: the air groups of three veteran aircraft carriers; 150 aircraft from Shokaku, Zuikaku, and Zuiho. They arrived on November 1.

  On October 29, the weather broke, letting Kenney resume his attacks against Rabaul. That day he sent one raid: 37 B-24s escorted by 53 P-38s. They conducted a high-altitude attack against Vunakanau. The Japanese scrambled 75 Zeroes to intercept them. The Japanese lost seven aircraft on the ground and six in the air. No US aircraft were shot down, but many were damaged. Although the Japanese were losing more aircraft and had fewer to start with, the cumulative damage was telling on both sides. Whereas the United States could send 100 fighters on October 12, they had only 53 operational on October 29.

  Weather closed down the Fifth Air Force from October 31 through November 1. Kenney next raided Rabaul on November 2. This time he decided to go after the shipping in Simpson Harbor. The invasion of Bougainville had started on November 1, and Kenney believed Simpson Harbor would offer a target-rich environment. This time the Fifth Air Force dispatched nine B-25 squadrons and six P-38 squadrons – 75 B-25s and 57 P-38s, about half the strength mustered three weeks earlier.

  Target-rich Simpson Harbor proved to be. In addition to the normal merchant traffic there, the Japanese had sent naval reinforcements from Truk: two heavy cruisers, two light cruisers, and two destroyers to augment the naval force stationed at Rabaul. These reinforcements were a little battered. They had fought a night engagement off Empress Augusta Bay during the pre-dawn hours of November 2. Their antiaircraft batteries were intact, however, adding to the already formidable array of guns ringing Simpson Harbor. Worse still, the Combined Fleet aerial reinforcements had arrived. The Fifth Air Force strike force was outnumbered. The attack was planned based on photo reconnaissance done following the November 29 raid. Planning missed both sets of reinforcements.

  The Americans flew up the St George’s Channel until they reached Crater Peninsula. They flew over the saddle formed by Mount Tovanurdatir and Mount Komvur. The raid started with two squadrons of P-38s strafing Lakunai. The Lightnings found their hands full. The Japanese had 100 fighters in the air, most from Lakunai. Having returned from a strike against the Bougainville invasion fleet that they had flown earlier in the day, some newly refueled Zeroes were taking off when the P-38s arrived.

  Meanwhile the B-25s and the three squadrons of fighters escorting them flew over Rabaul and into Simpson Harbor. The B-25s attacked in squadrons, each squadron trailing the one ahead by one minute. The bombers were armed with a mix of para-fragmentation bombs, 1,000lb demolition bombs, and 100lb phosphorus bombs. While relatively unmolested by enemy aircraft (Japanese fighters initially concentrated on the Lightnings strafing Lakunai), the harbor attack force flew into a heavy concentration of antiaircraft artillery, both ashore and aboard the Japanese warships. To make the odds stiffer, the Japanese cruisers opened up with their main batteries against the low-flying strafers.

  Back to base with the enemy in pursuit

  On October 18, the Fifth Air Force launched a follow-up strike on Rabaul
’s airfields. It was intended as another maximum effort, but due to weather, a mission abort was declared. The B-24s and P-38s returned home, but 50 B-25s, led by Lieutenant Colonel Clinton True, pressed on, attacking Tobera and Rapopo airfields. A low-level raid on Tobera was successfully executed with the attacking squadron successfully escaping and evading all but a handful of pursuing fighters, but the Rapopo attack was not nearly as lucky. The three squadrons pasted the airfield with .50-caliber fire and daisy-cutters, but as soon as they cleared the coast they ran into a buzz-saw of Japanese fighters.

  Having received warning of the impending raid, the two untouched airfields had sortied 40 Japanese fighters. They had been circling over the St George’s Channel, expecting the P-38s which normally accompanied the bombers. Instead they discovered the trailing squadron of withdrawing Mitchells as they cleared the coast north of Rapopo. The Zeroes, a mixture of A6M2s and A6M3s, pounced on the unescorted bombers. A long battle followed as the Mitchells flew east, trying to clear Cape Gazelle.

  The Zeroes ripped into the Mitchells, both singly and in pairs. For nearly 30 minutes the B-25s were pursued. The Zeroes flew in and out of the formation. The bombers tightened their formation, flying as close to each other as possible for mutual defense. They dropped down almost to wave-top heights to discourage diving attacks. The Japanese were so intent on their prey that some tried diving attacks anyway, misjudged the altitude, and struck the water. They continued their pursuit as the B-25s reached Cape Gazelle and turned south. Finally, the fighters thinned out, leaving the damaged bombers to complete the long trip home or divert to the closer Kiriwina.