by Mark Lardas
November 11 US Navy aircraft from Essex, Bunker Hill, Independence, Saratoga, and Princeton strike Rabaul, sinking or damaging four Japanese warships. Japanese counterstrikes are driven off with heavy loss to the Japanese, and little damage to the carrier strike group attacked.
November 12 Surviving aircraft of 1st Carrier Division are withdrawn, departing Rabaul for Truk.
November 14/15 Thirty-six Beauforts launch a nighttime torpedo attack against ships in Simpson Harbor.
December 10 Torokina airfield, Bougainville (fighter strip), becomes operational for Allied aircraft.
December 15 Arawe (on New Britain) is invaded, and the Japanese airfield there captured by US forces.
December 17 First Comairsols fighter sweep over Rabaul occurs, involving 80 Marine, Navy, and Royal New Zealand Air Force (RNZAF) aircraft.
December 23–30 Daily large-scale airstrikes are made against Rabaul by Comairsols bombers and fighters.
December 25 Aircraft from Bunker Hill and Monterey attack ships in Kavieng Harbor, facing minimal aerial opposition because its fighters were transferred to Rabaul due to an Allied feint.
December 26 Cape Gloucester invaded and Cape Gloucester airfield captured by US forces.
The scene during the height of the November 5, 1943 carrier strike on Rabaul. Aircraft from Saratoga and Princeton hit Japanese cruisers in Simpson Harbor. Cruisers and destroyers exit Simpson Harbor with one heavy cruiser (right center) hit. (USNHHC)
1944
January 2–9 Fighter sweeps and bombing by single-engine bombers is carried out against Rabaul, focusing on Japanese airfields.
January 9 Tobera airfield is temporarily closed by a bombing raid, the first time Allied bombing shuts down an airfield.
January 10 The bomber strip at Piva South airfield (Bougainville) becomes operational.
January 11 Comairsols B-25s attack Vunakanau airfield, the first B-25 attack launched from the Solomons.
January 14 Thirty-six SBDs and 16 TBDs attack Lakunai escorted by RNZAF P-40s and Marine F4Us. The attack is launched from Munda with refueling stop at Piva.
January 17 Comairsols begins launching almost daily heavy raids against Rabaul.
January 25 Sixth Attack Air Force is relieved by 2nd Carrier Division. Sixth Attack Air Force withdrawn to Truk.
February 10 Comairsols daily raids against Rabaul increase to over 200 aircraft per day.
February 15 Green Islands invaded and captured.
February 17–18 USN destroyers conduct night naval bombardment of Rabaul and Simpson Harbor.
February 18 Fifth Air Force raids knock out Kavieng airfields.
February 19 Rabaul installations attacked heavily by US Marine Corps (USMC), US Navy, and US Army Air Force (USAAF) aircraft.
February 21 Japanese abandon air defense of Rabaul, withdraw all remaining aircraft.
February 21 Convoy departing Rabaul is attacked and devastated by B-25s.
February 22 USN Destroyer Squadron 25 attacks and destroys remnants of convoy in surface action, marking naval isolation of New Britain.
February 25 Second naval bombardment of Rabaul.
February 29 Third naval bombardment of Rabaul.
February 29 Manus and Los Negros Islands in Admiralties invaded.
March 1 Comairsols begins bombing campaign to obliterate Rabaul city.
March 8 Nissan airfield (in Green Islands) operational.
March 9 Allied bombers begin unescorted missions to Rabaul.
March 20 Marines land on and occupy Emirau.
April 8 Daily raids against Japanese supply dumps cease due to a lack of targets.
April 14 Emirau airfield opens.
April 20 Daily mass raids against Rabaul city cease due to a lack of targets. City 90 percent destroyed.
April 21 on Small air raids continue over Gazelle Peninsula to keep Rabaul and its airfields suppressed. These continue through January 1945.
May 2 Emirau airfield operational.
1945
August 15 Japan unconditionally surrenders to Allied powers.
September 6 Japanese forces at Rabaul surrender to the Australians.
ATTACKERS’ CAPABILITIES
Fifth Air Force and Comairsols
Rabaul was at the junction of two major Allied Commands: the Southwest Pacific Area under Douglas MacArthur and the South Pacific Area commanded by William Halsey for Admiral Chester Nimitz. The South Pacific Area also contained significant US Army forces. The attack on Rabaul drew the resources of three independent air commands: the Fifth Air Force in MacArthur’s command, the US Army Thirteenth Air Force (part of the South Pacific Command), and Navy and Marine Corps air assets in the Solomon Islands and surrounding territory. USAAF, Navy, and Marine aircraft in this region were consolidated into Comairsols (Command Air, Solomons), but cooperation between Comairsols and the Fifth Air Force had to be negotiated.
The Grumman F6F Hellcat was the fighter most feared by Japanese fighter pilots at Rabaul. It could not reach Rabaul until Allied airfields became available on Bougainville. (USNHHC)
Allied success would depend upon Comairsols having sufficient aircraft with the right capabilities, an airbase infrastructure from which to launch a concentrated air assault on Rabaul, and the weapons and tactics to effectively destroy Japanese facilities, aircraft, and ships. Long-range bombers and fighters could reach Rabaul from existing airfields, but shorter-ranged, higher-performance single-engine fighters needed closer bases to operate over Rabaul, as did the specialist torpedo bombers and dive bombers. Between March and the start of October the Allies focused on developing infrastructure, both by constructing new and acquiring existing airfields and by reducing Japan’s ability to attack these new airfields.
Aircraft were drawn from the Fifth and Thirteenth Air Forces of the USAAF. There were 13 land-based naval squadrons, 33 USMC squadrons, and 14 carrier-based naval squadrons on five aircraft carriers. During the first six months of 1943 US forces perfected new weapons and tactics, adding significantly to the air offensive against Rabaul which started in October 1943.
Aircraft in theater
Eight main aircraft types – five bomber and three fighter – were used by the Allied forces to reduce Rabaul. These were:
Consolidated B-24 Liberator
Called the PB4Y by the US Navy, the Liberator was a four-engine heavy bomber. It could carry up to 8,000lb of bombs internally, but its normal bomb load was 5,000lb. It had a maximum speed of 300mph, a cruising speed in formation of 180– 210mph, and a range of 3,000 miles. Although it could be used as a medium- or low-level bomber, on bombing missions against Rabaul it was normally used as a high-level bomber, typically operating at 18,000–25,000ft. It was also used for reconnaissance or maritime patrol, particularly by the Navy and the Thirteenth Air Force. The Fifth Air Force deployed 12 B-24 squadrons; the Thirteenth Air Force seven, and the US Navy one squadron of PB4Ys, each squadron nominally with 12 aircraft. The Fifth Air Force could theoretically commit over 140 B-24s, but the most ever sent on a single raid was 90.
B-25s with eight forward-firing .50-caliber machine guns were field modifications performed in New Guinea using machine guns from wrecked fighters. North American, the manufacturer, eventually built similar aircraft in their factory. The aircraft being serviced here on a Pacific island was factory-built. (AC)
North American B-25 Mitchell
Called the PBJ when used by the US Navy or Marine Corps, the Mitchell was a twin-engine medium bomber. It carried up to 5,000lb of bombs and had a range of 3,000 miles, a top speed of 272mph and a cruising speed of 230mph. Most B-25s used in the campaign were field-modified to add eight forward-firing .50-caliber machine guns. The Mitchell was used primarily as a low-level attack bomber, particularly against airfields and shipping. After the Japanese defenses were suppressed it was used as a medium-level bomber against Rabaul city. The Fifth Air Force had eight 16-aircraft squadrons of B-25s, the Thirteenth Air Force six squadrons, the Navy four squadrons, and Ma
rines five. The Fifth Air Force flew raids with as many as 75 B-25s in a single raid. Comairsols raids tended to use smaller numbers, typically 24–36. Despite its smaller size, the B-25 proved the decisive weapon in the campaign against Rabaul, as its combination of virtues was right for the low-level role. It was relatively maneuverable, carried a useful bomb load, and had the additional strafing punch of its eight .50-calibers.
Grumman TBF Avenger
The Avenger was a single-engine torpedo bomber used by the US Navy and the Marine Corps. It had a crew of three and could carry a single 18in aerial torpedo or 2,000lb of bombs. It had a range of 1,000 miles, a top speed of 275mph, a cruising speed of 145mph, and a service ceiling of 30,000ft. The Avenger was operated by both land-based and carrier-based squadrons. Used as a torpedo bomber during the early phases of the Rabaul campaign, it was later used as a medium-altitude or high-altitude level bomber, when few ships worth a torpedo remained near New Britain. Three shore-based naval squadrons, five shore-based Marine squadrons, and five carrier-based Avenger squadrons were used during the campaign.
Douglas SBD Dauntless and Curtiss SB2C Helldiver
These were two single-engine dive bombers used by Navy and Marine squadrons during the campaign. The Dauntless could carry up to 2,250lb of bombs. It had a maximum speed of 255mph, a cruise speed of 185mph, a service ceiling of 25,500ft, and a range of 1,100 miles. The newer and more powerful Helldiver carried a bomb load of up to 2,500lb. It had a maximum speed of 295mph, a cruise speed of 158mph, a ceiling of 29,000ft, and a range of 1,165 miles. The Helldiver was a replacement for the Dauntless. At least two carrier-based squadrons were used during the campaign. Two land-based and three carrier-based Navy squadrons used SBDs during the campaign, as well as eight land-based USMC squadrons. The Marine squadrons began replacing Dauntlesses with Helldivers in the last months of the campaign.
THREE WAYS TO ATTACK AN AIRFIELD
Allied air forces used three basic methods to destroy Japanese airfields: low-level strafing and bombing, high-level bombing, and dive bombing. Each was conducted in a different manner, and had different attributes.
High-level bombing: High-level attacks were made at 20,000ft, near the operational limit of antiaircraft artillery. The bombers flew over the target in a bomber box formation and attempted to saturate the field with a carpet of bombs. Usually flown by B-24s. Advantages: Allowed large numbers of aircraft to simultaneously attack airfield. Flew at or above the ceiling of antiaircraft guns. Box formation offered protection against enemy fighters. Disadvantage: Accuracy diminished by altitude. Many aircraft required.
Dive bombing: Dive bombers attacked in formations of three to six aircraft. They approached at 10,000–12,000ft, picked a specific target, and dived on it at a 70-degree angle, pulling out of the dive at 1,000–2,000ft after releasing their bomb. Typically flown by Douglas Dauntlesses. Advantages: Allowed precision targeting of high-value targets such as antiaircraft gun emplacements. Diving bombers were hard to hit with antiaircraft fire and difficult for fighters to engage. Disadvantages: Dive bombers were often relatively slow and thus vulnerable to fighters and antiaircraft guns prior to entering dives. They also had a shorter range than multi-engine bombers.
Low-level attack: Low-level attacks were made at treetop level by shallow vees of medium bombers, flying under antiaircraft fire. Typically one squadron (12–18 aircraft) attacked at a time, with each wave of aircraft separated by 30 seconds. They strafed their targets, and dropped parachute-retarded time-delay bombs. Typically flown by B-25s. Advantages: Difficult for airfield defenders to attack very low formation. Allowed accurate targeting of targets. Disadvantage: Difficult to launch mass multi-squadron attacks due to risk of trailing aircraft being damaged by bombs from earlier waves.
Lockheed P-38 Lightning
A twin-engine long-range fighter used by the US Army, it had a maximum speed of 414mph, a cruise speed of 275mph, a 1,300-mile range, and a service ceiling of 44,000ft. It was armed with one 20mm cannon and four .50-caliber machine guns, mounted in the nose. Although vulnerable in a dogfight, its high speed and ceiling allowed the Lightning to pick its battles. It was used exclusively by the USAAF. The Fifth Air Force had six squadrons of P-38s, and committed as many as 70 Lightnings to escort bombers to Rabaul. The Thirteenth Air Force had four P-38 squadrons.
The P-38 could escort bombers from Port Moresby to Rabaul, but flew from airfields at Kiriwina and the Woodlarks. Less maneuverable than the Corsair or Hellcat, properly handled the Lockheed Lightning could match the Japanese fighters. It was the key to the Fifth Air Force’s Rabaul offensive. (AC)
Grumman F6F Hellcat
The successor to Grumman’s F4F Wildcat, the Hellcat was designed to give the US Navy a fighter that outmatched the Zero. It first saw combat in September 1943, and was the Allied fighter most feared by Japanese pilots. The Hellcat was armed with six .50-caliber machine guns and had a maximum speed of 391mph, a cruising speed of 200mph, a service ceiling of 37,300ft, and a range of 1,500 miles. It was the primary carrier-based fighter of the war in 1943–44, although it was also used in land-based squadrons. The Navy used four land-based and six carrier-based F6F squadrons against Rabaul.
Vought F4U Corsair
The Corsair was a single-engine fighter, armed with six .50-caliber machine guns. It had a top speed of 417mph, a cruise speed of 215mph, a service ceiling of 36,000ft, and a range of 1,000 miles. It had been designed as a carrier aircraft, but proved difficult to land on an aircraft carrier. In 1943–44 it was assigned to land-based squadrons, although on at least one occasion during this campaign land-based F4Us landed on aircraft carriers to refuel. The Corsair was the dominant fighter of the campaign. The Navy had one squadron of land-based Corsairs and the USMC had 14.
Other aircraft types
The PBY Catalina was an amphibian used for long-range reconnaissance, night antishipping attacks, and air-sea rescue. The USAAF had several squadrons equipped with P-39 Airacobras and P-40 Warhawks. The Airacobra had a 37mm cannon and was used for ground support. The P-40s tended to be used for airfield defense. Since the Japanese made only two airstrikes on Fifth Air Force airfields their role was minimal. The Navy also used the Ventura in a minor role as a patrol bomber.
The RAAF and the Royal New Zealand Air Force (RNZAF) also contributed aircraft used in this campaign. The RAAF had several squadrons of Beaufighters and Beauforts supporting the siege. Both were twin-engine aircraft. The Beaufort was a torpedo bomber, used primarily for night strikes. The Beaufighter was a fighter version of the Beaufort. Intended as a night fighter, it was used to attack airfields. The RNZAF had several Kittyhawk (an export version of the P-40) squadrons stationed in the Solomons. These participated in several fighter sweeps.
The need for bases
Fifth Air Force’s success in the March 1943 battle of the Bismarck Sea demonstrated that if the Allies gained air superiority over the Gazelle Peninsula, Rabaul could be effectively isolated without an invasion. But mounting a sustained aerial attack against Rabaul required airfields within range of the target and their associated facilities. It also meant secure supply lines for the airfields and for troops holding the ground around the airfields used.
In January 1943, when Rabaul was made an objective, the nearest available operational airfields to Rabaul were Port Moresby and Guadalcanal. (Dobodura airfield, newly built on the northern coast of New Guinea, was operational, but operations there were still focused exclusively on supplying and protecting Dobodura itself.) Guadalcanal was 650 miles from Rabaul which placed it out of range of all but long-range bombers, unescorted by fighters. Port Moresby was 485 miles from Rabaul, at the ragged edge of the limit for P-38s to escort Fifth Air Force bombers. Missions from it were complicated by the need to fly over the 13,000ft-high Owen Stanley mountain range shortly after take-off, while heavily laden with bombs and fuel.
The ability of the Allies to quickly build airfields contributed significantly to victory. An airfield could be completed in as lit
tle as two weeks. This photo shows an airfield being built. It is Day 8, and the engineers are rolling and grading the runway. (AC)
By March 1943, when the decision was made to isolate Rabaul purely through air power, facilities had improved, but only marginally. The new airfield at Dobodura was finally operational. Dobodura was only 390 miles from Rabaul, allowing P-38s to reach Rabaul with enough fuel to protect the bombers. Dobodura also eased the challenge of overflying the Owen Stanley Range, as bombers could stage from the new airfield, having topped up their fuel tanks there. From Dobodura the Fifth Air Force was within effective range of Rabaul. Yet the Fifth Air Force had other, nearer enemies at hand, notably at Lae, Finschhafen and Wewak. Japanese air power on New Guinea proved a more immediate threat. Dobodura was ideally placed to deal with these and, as the battle of the Bismarck Sea proved, to sever New Guinea from receiving reinforcements from New Britain.
However, Dobodura was not the ideal platform from which to attack Rabaul. Only multi-engine aircraft could reach the Gazelle Peninsula from there, and the twin-engine P-38 was not a sufficiently agile fighter to be used to wear down the Japanese Zeroes on Rabaul. Single-engine fighters were necessary to gain air superiority, and being able to use land-based dive bombers would give the Allies important precision-bombing capabilities.
The next six months, from April 1943 through mid-October 1943, were therefore devoted to obtaining airfields closer to Rabaul. In April 1943 US Army troops landed on the Woodlark Islands and Kiriwina, lightly held islands where airfields were built. Woodlark was 345 miles from Rabaul while Kiriwina was only 310 miles. In the Solomons, Marines and Army forces began moving up the island chain. In August, Marines landed on New Georgia, seizing the Japanese airfield at Munda, 440 miles from Rabaul. Vella Lavella followed. By late September an airfield there was available. By the start of October the Allies held former Japanese strongpoints in New Guinea, including Lae and Finschhafen.