Fortress Rabaul: The Battle for the Southwest Pacific, January 1942-April 1943

by Bruce Gamble

  That very afternoon, a message outlining Yamamoto’s proposed visit was drafted for the purpose of notifying the outlying bases. The information was laid out precisely: the date and time of Yamamoto’s departure from Rabaul (April 18, 0600), the location of the first stop and estimated time of arrival (Ballale, 0800), the type of aircraft Yamamoto and his staff would ride in (land-based medium bomber), the number of escorts (six fighters), and the exact itinerary to be followed throughout the day.

  Using a new naval code that had gone into effect only two weeks earlier, the message was transmitted from Rabaul a few minutes before 1800, Japan Standard Time. Powerful, low-frequency radio waves radiated outward from the transmitter in all directions and within seconds were received by the intended addressees. Decoding the message took a bit longer, but the information was delivered as intended throughout the lower Solomons. One recipient, Rear Adm. Takatsugu Jojima, commander of the 11th Seaplane Tender Division based at Shortland Island, was immediately critical of the transmission. “What a damn fool thing to do, to send such a long and detailed message about the activities of the C-in-C so near the front,” he said to his subordinates. “This kind of thing must stop.”

  At Rabaul, Admiral Ozawa also voiced his opposition, but Yamamoto refused to change his mind. Ozawa then appealed to Capt. Kameto Kuroshima, a senior member of Yamamoto’s staff. “If he insists on going, six fighters are nothing like enough,” Ozawa said. “Tell the chief of staff that he can have as many of my planes as he likes.” But Ugaki was in the hospital with dengue fever, and Ozawa’s pledge was not delivered.

  Yamamoto’s fleet commanders were right to be concerned. The radio waves that carried the encrypted message did not simply stop; instead they kept radiating outward, bending around the curvature of the Earth, bouncing from clouds, and within seconds of transmittal they were picked up by American listening posts. At Pearl Harbor, room-sized IBM card-reading machines sorted through the variables of the updated naval code and detected the message’s heading: C-in-C, Combined Fleet. That alone was enough to put the human code-breakers on high alert. Veteran cryptanalysts soon filled in many of the blanks that the primitive computer missed and realized that the message represented far more than a travel itinerary. The wealth of details placed the man who had masterminded the attack on Pearl Harbor in an extremely vulnerable situation. His flight to Ballale would bring him within 325 statute miles of Guadalcanal. “This is our chance to get Yamamoto,” said an officer at the Fleet Radio Unit.

  That morning, April 14, a copy of the message was delivered to Admiral Nimitz. For a short while he deliberated the pros and cons of using the information to eliminate Yamamoto, but the decision was really quite simple. As author Donald Davis later put it, Yamamoto represented “the hated face of the Japanese war machine… . Killing him would be a horrific setback for Japan, and, for America, payback for Pearl Harbor.” Nimitz gave the go-ahead, and by midmorning the message had been forwarded to South Pacific Area headquarters on New Caledonia. From there it went to Rear Adm. Marc A. Mitscher, commander of aircraft operations in the Solomons (abbreviated as COMAIRSOLS). In turn, Mitscher called a secret meeting for his staff, where it was determined that any possible interception of Yamamoto’s flight would have to be conducted by P-38s, the only type of fighter at Guadalcanal with the range to fly to Bougainville and back. Because the Solomons were west of the International Date Line, it was already April 15, which gave Fighter Command less than three days to plan the most important mission of the war.

  AT RABAUL, Yamamoto wore his dress whites again on April 14 to send off the next attack, a two-pronged mission labeled “Y-1” and “Y-2.” Seventy-five fighters and twenty-three dive-bombers from the Third Fleet, joined by fifty-four fighters and forty-four medium bombers of the Eleventh Air Fleet, took off to attack the harbor and airfields at Milne Bay. Along the way, four bombers of Air Group 751 turned back, and two others were damaged in a midair collision, but the force remained powerful with nearly two hundred aircraft.

  For all the armada’s potential, however, the Japanese failed once again to deliver a knockout blow. Three Allied ships were hit at Milne Bay, but only one was seriously damaged. Forty-four Allied fighters intercepted the Japanese and claimed nineteen “confirmed” kills, plus six additional planes as probably destroyed, but the raid actually cost the Japanese only eight aircraft. Similarly, losses for the Allies amounted to just one P-40 and its pilot. Four other P-40s were “pretty badly shot up,” and one P-38 crash-landed.

  Back at Rabaul, the returning aircrews reported hugely inflated results again: three large transports and one medium transport sunk, six transports damaged heavily and set on fire, forty-four Allied planes shot down for certain. That night, Rear Admiral Ugaki believed he had reason to gloat in his diary:

  Today’s operations of Y-1 and Y-2 a great success. Congratulations! But at the same time our losses gradually increased too. This was natural. A telegram from the chief of the Naval General Staff stated that when he reported the result of Operation Y-1 and Y-2 to the emperor, His Majesty gave the following words: “Please convey my satisfaction to the commander-in-chief, Combined Fleet, and tell him to enlarge the war result more than ever.”

  A fighter sweep was planned for April 16, which gave the Japanese a full day to prepare the aircraft, but when reconnaissance flights failed to turn up adequate targets on New Guinea’s northeast coast, the raid was called off. As Yamamoto and his staff compiled the reports from the previous missions, they were convinced that the Allies had suffered tremendous harm. Aggregate claims for ships sunk at Guadalcanal and New Guinea included one cruiser, two destroyers, six large transports, and ten medium transports. Japanese aircrews and fighter pilots also claimed to have shot down 134 Allied planes for certain and damaged another 56. But as Ugaki pointed out in his diary, Japanese losses were mounting. After a week of conducting large-scale attacks, 26 percent of the Vals had been expended along with 18 percent of the land-based Bettys. Given the apparent success of the attacks and the trend in friendly losses, Yamamoto ordered the conclusion of I-Go Sakusen.

  The next morning, April 17, Vice Admiral Ugaki chaired a conference at 8th Base Force headquarters to review the lessons learned from the aerial offensive. Numerous high-ranking naval officers were present, including Yamamoto, who was content to observe while the aviation gurus discussed important matters. One topic that generated keen interest was the tendency of Japanese warplanes to catch fire after just a few hits with incendiary or even tracer rounds. That the experts even acknowledged the problem was unusual. The Japanese were highly reluctant to admit that hundreds of aviators had been burnt to a crisp because the aircraft engineers scorned the weight penalty of protected fuel tanks. To the contrary, the Japanese typically accounted for their losses by applying reverse psychology: whenever one of their aircraft burst into flames or was otherwise shot down during combat, it wasn’t entirely because the enemy had scored fatal hits; instead, the plane had merely been damaged, and its pilot decided to blow himself up (along with his crew, if applicable) as a symbolic act of suicide.

  The Japanese called this jibaku, which literally means to self-explode. The amazing thing is that so many aviators, for all their intelligence and technological expertise, were brainwashed by the bushido mentality. Petty Officer Igarashi was a perfect example. Upon learning that one of his friends in Air Group 705 was shot down on April 14, he evoked the concept of jibaku as if it were the most natural thing in the world: “In the afternoon I went to the airfield again and heard about the great progress of the battle. More than ten vessels were sunk, airfields were on fire, etc. Unfortunately, Yokozawa self-exploded with Lieutenant Matuoka.”

  After losing numerous dive-bombers and land-based medium bombers during the one-week operation, the conference attendees admitted that their planes needed “bullet protection,” as they quaintly put it. Heretofore, the aviation community had operated under the premise that the best defense was a good offense. In applying the sam
urai ethic to twentieth-century war machines, fliers and engineers alike valued speed, agility, and lightness above all other qualities. If a plane and its pilot were appropriately aggressive, there was little need for heavy armor plating or protected fuel tanks. As an extension of that mindset, most fighter pilots removed the radios from their planes, and many refused to wear a parachute because they considered the weight excessive.

  One positive outcome of the conference, at least from the Japanese point of view, was to affirm their belief that the Zero was still the most dominant fighter in the war. The Japanese did, however, express concern about the new American fighter they were encountering in the Solomons, the Vought F4U Corsair. In spite of themselves, they were impressed by the fighter’s superior horizontal speed, rate of climb, armament, and ruggedness. “While their numbers were small, the F4Us caused no trouble,” wrote Akira Yoshimura. “But as their numbers rapidly increased, it … became impossible to ignore this new fighter. The [attendees] had to admit that at last an American fighter able to match the Zero had appeared.”

  Another outcome of the conference was a situation report from Lieutenant General Adachi, who had returned from a recent inspection trip to New Guinea. Despite the string of losses there, he informed Yamamoto and the assembled leaders that if he could have another battalion, he would be able to hold his current positions. It was an illusion. Adachi was probably telling the navy what he thought they wanted to hear, but it worked. Both Yamamoto and Ugaki were pleased to receive the favorable news, which made them more eager than ever to visit the forward bases in the Solomons and inspire the men serving there.

  Rear Admiral Johima, who had flown to Rabaul to attend the conference, warned Yamamoto against making his planned excursion to Bougainville. The flight was too dangerous, Johima said, but Yamamoto would not back down. “I have to go,” he replied. “I’ve let them know, and they’ll have got things ready for me. I’ll leave tomorrow morning and be back by dusk. Why don’t we have dinner together?”

  A STICKLER for punctuality, Isoroku Yamamoto arose early on the morning of April 18. The flight to the Solomons was scheduled to depart from Lakunai airdrome at 0600. An artistic individual, fond of writing haiku poems and creating exquisite examples of calligraphy, Yamamoto might have allowed himself a few minutes to indulge in the beauty of the tropical morning. The skies were clear, bringing the promise of a pleasant day, and a gentle sea breeze brought the scent of frangipani and bougainvillea wafting through the louvered shutters of the cottage.

  For the first time since leaving Japan, Yamamoto donned a new uniform of green khaki instead of dress whites. He also wore a pair of comfortable airmen’s boots, and completed his ensemble by attaching a traditional sword to his uniform belt. The weapon he selected had been a gift from his older brother, who was now deceased.

  After breakfast, Yamamoto met Vice Admiral Ugaki outside his quarters. The chief of staff thought their new khakis looked “gallant,” but he also had to admit that seeing Yamamoto in the dark green uniform for the first time was “a bit strange.” They climbed into a car for the short ride to Lakunai and arrived precisely at 0600.

  The traveling staff, arriving in several cars, pulled up alongside two Type 1 rikko from Air Group 705, brought over that morning from Vunakanau. Admiral Ozawa was on hand for the departure, but Yamamoto did not linger before boarding his aircraft. In accordance with standard precautionary measures, the Combined Fleet Staff was divided between the two bombers: Yamamoto and three officers climbed aboard an olive-colored Betty with the number 323 painted on its vertical stabilizer, while Ugaki and three other staff officers were seated in the second Mitsubishi, numbered 326.

  The bombers took off to the southeast, passing over Matupit Harbor and the gaping crater of Tavurvur as they climbed. Behind them, six fighters of Air Group 204 roared up from the same airdrome and formed into two shotais, one taking position on the right side of the bombers, the other on the left. The pilot of the trailing bomber, FPO 1st Class Hiroshi Hayashi, tucked in close along the left side of the lead aircraft, skillfully maintaining such a tight formation that Ugaki was afraid “their wingtips might touch.” But the chief of staff also appreciated being able to clearly see Yamamoto, who occupied the left front seat of the lead bomber, piloted by CPO Takashi Kotani.

  THE BOMBERS’ FIRST destination was Ballale, an island so tiny that its crushed-coral airstrip reached from one side of the island to the other. Officially part of the Shortland group, the arrowhead-shaped isle lay fourteen miles southeast of Moila Point on the tip of Bougainville. The airfield was built by the Imperial Navy’s 18th Construction Battalion, headed by Lt. Cmdr. Noriko Ozaki, between November 1942 and January 1943. Because the Japanese had no bulldozers for such big projects, much of the labor was done by hand. In early December 1942, a shipment of 517 POWs arrived from Rabaul to work on the airfield—and therein lay another dark story of Japanese atrocities.

  Known unofficially as the “Gunners 600,” the prisoners sent to Ballale were among the thousands of British soldiers captured after the surrender of Singapore the previous February. Some 50,000 POWs were initially held near Changi Prison, but in mid-October about 600 Royal Artillerymen were sent to New Britain. After three weeks of misery at sea aboard a “hellship,” they arrived at Kokopo on November 6. One prisoner had died en route, and many others were sick with dysentery, beriberi, and malaria. About a week later, 517 men were sent on to Ballale, leaving 82 of the sickest at Kokopo.

  From the time of their arrival at Ballale, the British gunners were harshly treated. Ozaki himself was said to have beheaded a prisoner the next day, no doubt to establish his absolute authoritarianism. The POWs, housed in a compound of huts near the southwestern end of the airstrip, received no medical attention and were not allowed to dig or construct air-raid shelters. Korean laborers, Chinese prisoners, and native islanders also worked on the airfield, but they were strictly prohibited from making contact with the white prisoners.

  The island’s occupants were all living on borrowed time. On January 15, 1943, a single B-17 from Guadalcanal bombed the airstrip, and within a matter of weeks, aerial attacks became heavier and more frequent. Unknown to the American aircrews, dozens or possibly even hundreds of POWs were killed by friendly bombs. The Japanese permitted the burial of the victims, whereas POWs who died due to illness or neglect were placed in rice sacks and dumped at sea. By the time Yamamoto’s party approached Ballale, the tiny island had been hit at least fourteen times—and only a few dozen of the original 517 gunners were still alive.

  Whether Yamamoto was aware of the British prisoners at Ballale is unknown. Either way, the gaunt, sickly survivors would probably have been kept out of sight while the commander in chief visited the garrison. There is no point in speculating further, however, because Yamamoto never reached the island.

  AT 0710 ON SUNDAY, April 18, celebrated around Christendom as Palm Sunday, Maj. John W. Mitchell gunned his P-38 Lightning down the airstrip known as Fighter 2 on Guadalcanal. Behind him, seventeen hand-picked pilots—eight from the 339th Fighter Squadron commanded by Mitchell and nine from the 12th Fighter Squadron—waited their turn to roll. Over the past two days, aided by the expert staff at Fighter Command, Mitchell had carefully scripted a mission to intercept Yamamoto’s flight. A circuitous route, nearly five hundred statute miles in length, would be flown well out to sea at barely fifty feet of altitude to avoid all possibility of detection by Japanese coastwatchers. Navigation would rely entirely on dead reckoning, since the airmen would be flying too low to see any landmarks. Therefore, the compass headings, air speeds, and timing of the route’s five legs were laid out as precisely as possible. Yamamoto’s punctuality was well known to Allied intelligence, so Mitchell designed a scheme to catch the entourage at a point along the Bougainville coast, about ten minutes before the flight neared the airdrome at Buin. Four of the pilots, led by Capt. Tom Lanphier, were assigned as the “killer” flight. The remaining sixteen Lightnings would provide cover aga
inst counterattacking Zeros.

  Within minutes of Mitchell’s takeoff, two Lightnings were scrubbed: one with a blown tire, the other with fuel transfer problems. Both were part of the attack flight, so two designated alternates—lieutenants Besby F. Holmes and his wingman, Raymond K. Hine—slid into the vacated spots. In all, sixteen pilots joined up and skimmed the waves as they headed outbound on the first leg of their roundabout route. At sea level the temperature was above ninety degrees, which meant the pilots sweated profusely as the sun blazed through their Perspex canopies. Mitchell’s wingman, 1st Lt. Julius Jacobson, wondered how his squadron leader was handling the extraordinary responsibilities. He could only imagine the critical questions that must have constantly cycled through Mitchell’s mind:

  Am I on course?

  Did I turn to the compass heading on time?

  Are the winds as predicted?

  Will Yamamoto be there when we arrive?

  Can we get him?

  After completing the first four legs as carefully as he knew how, Mitchell turned to the final heading, which was pointed right into the morning sun. If everything went according to plan, the nineteen-mile-long northeasterly track would bring the P-38s to the coast of Bougainville in the vicinity of Torokina village, where they would intersect the path of Yamamoto’s aircraft at right angles.

  The Lightning pilots squinted hard, trying to see through the glare caused by a thin layer of haze. So far they had maintained strict radio silence, but a few minutes into the final leg, the voice of 1st Lt. Douglas S. Canning suddenly filled their earphones: “Bogeys, ten o’clock high!”