The 1922 treaty also affected the size and capability of Japan’s next carrier, though in a different way. Because Kaga and Akagi took up such a large percentage of Japan’s available tonnage for carriers (81,000 tons), Japanese designers tried to build a carrier that displaced less than 10,000 tons in order to squeeze it in under the treaty’s definition of a capital ship. It didn’t work. The Ryūjō, laid down in 1929 and commissioned in 1933, simply could not accommodate all the necessary functions with so small a hull, and during construction her displacement crept up to 12,500 tons, though this was kept a secret at the time so that Japan would not be found in violation of the treaty.
In December of 1936, when the government formally renounced the Washington Treaty, Japan embarked on a naval expansion program that produced four new big-deck carriers in as many years: the Sōryū and the Hiryū, each of them displacing just under 20,000 tons when fully loaded and capable of carrying sixty-three airplanes each, and the Shōkaku and Zuikaku, at 32,000 tons and capable of carrying seventy-two planes each. These last two were commissioned in 1941, only four months before the attack on Pearl Harbor. By the end of 1941, the Japanese had a total of ten carriers, which were collectively capable of carrying over six hundred airplanes.*
The idea that Japan’s six biggest carriers should operate as a single task group may have originated with Genda Minoru, a precocious and outspoken advocate of air power, who claimed that he got the idea while watching a U.S. Navy promotional film of all four of America’s carriers steaming together. The film was merely a publicity shot for the movie-house newsreels, but Genda saw at once that deploying carriers that way for battle would allow a naval power to apply Mahanian principles of fleet concentration to air warfare. The formal proposal came from Genda’s superior, Rear Admiral Ozawa Jisaburō, commander of Carrier Division 1, who proposed in 1940 that all Japanese naval air assets, both land-based and sea-based, be placed under a unified command as the First Air Fleet. Yamamoto was initially cool to the idea, and he was a bit miffed when Ozawa went over his head to propose it directly to the Navy Ministry. But after the Naval General Staff approved it in April, 1941, Yamamoto willingly implemented the new organization. Five months later, when the new Shōkaku and Zuikaku joined the fleet, he grouped all six of the big carriers into a single command—the Kidō Butai.15
The commander of this awesome concentration of naval air power was Vice Admiral Nagumo Chūichi. Four years younger than Yamamoto (the same age difference as between Ernie King and Chester Nimitz), Nagumo was a graduate of the Torpedo School, and for most of his career had been affiliated with the fleet faction, less because of a strong commitment to its ideology than because it was the dominant faction of the Navy leadership and therefore helpful to him professionally. That put him on the opposite side of most interservice arguments from Yamamoto and contributed to a strained command relationship with his boss. Moreover, unlike the austere and stoic Yamamoto, Nagumo was a worrier by nature who fretted over even small details. Occasionally he would call junior officers into his office to solicit reassurance from them that things were progressing as they should. His official photograph depicts him staring rather perplexedly into the camera lens as if he were unsure why he was there. Genda was unimpressed with him and asserted that although Nagumo “was thought to be very gallant and brave[.] actually he was very cautious.” Yamamoto’s chief of staff, Ugaki Matome, agreed, confiding to his diary that Nagumo was insufficiently bold to be a successful commander. “He is not fully prepared yet to advance in the face of death and gain results two or three times as great as his cost by jumping into the jaws of death.” Nagumo, in short, was no gambler.16
Vice Admiral Nagumo Chūichi commanded the six big carriers of the Fleet Striking Force—the Kidō Butai—from the attack on Pearl Harbor through the Battle of Midway. (U.S. Naval Institute)
If Nagumo was not prepared to “jump into the jaws of death,” Yamamoto was. It was the gambler Yamamoto who conceived of, and then insisted upon, the Pearl Harbor operation. The government made the decision for war in October of 1941. While it was true enough that “those damn fools in the Army” (to repeat Yamamoto’s phrase) were the initial champions of war, junior and middle-grade officers of the Imperial Navy’s fleet faction proved enthusiastic partners. By 1941 opposing war within the Navy had become, in the words of one admiral, “like rowing a boat against the current … above Niagara Falls.” To gain access to the resources of South Asia, the plan was to strike south and occupy not only the Dutch East Indies and British Malaya, including its citadel at Singapore, but also the American-held Philippines. The planners accepted the fact that this meant war with Britain, Holland, and the United States, but they were not deterred.17
Yamamoto insisted that since Japan was to fight the United States, it was essential to begin with a preemptive strike against the American battle fleet. “The most important thing we have to do first of all in a war with the U.S.,” he wrote to the Navy Ministry in January 1941, “is to fiercely attack and destroy the U.S. main fleet at the outset of the war, so that the morale of the U.S. Navy and her people goes down to such an extent that it cannot be recovered.” When members of the Naval General Staff balked at so dramatic a move, Yamamoto let it be known that unless his plan was adopted, he and his entire staff would resign. That settled the matter. Though the strategic objective was the resource base in South Asia, the war would begin with an attack on Pearl Harbor, and the instrument of that strike would be the Kidō Butai under Nagumo Chūichi.18
When the six carriers of the Kidō Butai departed the Kurile Islands in the far north of Japan for Pearl Harbor, their hangar decks were packed with some of the best combat aircraft in the world. Airplane development in Japan had come a long way in a short time. Though Japan had begun designing and building her own battleships as early as 1910, she did not cast off her dependence on foreign designers and begin to produce her own combat aircraft until 1932. All-metal monoplanes replaced the cloth-covered biplanes that had been the mainstay of Japanese (and American) naval air power. Though the aircraft industry in Japan was putatively private, the government asserted more and more control over production after the beginning of the China Incident in 1937.19
The war in China proved both a blessing and a curse for Japanese aircraft design. It gave Japanese designers and engineers a vital testing ground for their combat aircraft. However, the experience also led the Japanese to underestimate the importance of armor protection and to place undue emphasis on range and maneuverability. Most technologies are a product of the culture that spawns them. The decision to minimize the importance of armor derived from a Japanese worldview that valued attack over protection. As a result, Japanese airplanes carried heavy armament but little armor; they could fly long distances on a single tank of fuel, but those fuel tanks were not self-sealing, which meant that a single bullet could ignite an explosion. Japanese combat aircraft were lighter and more nimble and had greater combat range than their Western counterparts, but they were also much more vulnerable.
Another weakness was that even in 1941 much of the work in Japan’s aircraft factories was still done piecemeal, by hand. One modern expert estimates that “half of all riveting and one-third of all sheet-metal processing in the Japanese aircraft industry was done by hand.” That was due in part to the fact that Japan was still industrializing in the 1930s, but another major factor was the Japanese preference for quality over quantity. It seemed more important to them to have one hundred airplanes of the highest quality than two hundred that were merely adequate.20
This mindset helped make Japan’s carrier airplanes among the best in the world, and this in turn contributed to the decision to go to war with the United States in the first place. It also meant that once the war began, Japan would be unable to produce replacement airplanes quickly or in large numbers. During 1941, even as Japan prepared to start a war that had already been decided upon, its aviation industry was producing only about 162 airplanes a month. By contrast, Roosevelt
called for the construction of 4,000 planes a month in 1942, and by the following year U.S. plants were turning out 10,000 planes a month. Japanese industry was simply incapable of matching such productivity.* In December of 1941, however, Japan’s leaders ignored this inherent weakness. Like Confederate soldiers in 1861 who believed that one Reb could whip five Yanks, they were convinced that Yamato damashii could overcome both numbers and industrial superiority. “You could quote them figures till you were blue in the face,” one officer remembered later of the Japanese high command, “but they’d have none of it.” This is what Navy Captain Ōi Atsushi meant when he wrote after the war, “The Japanese people are romantic and illogical.”21
Japan’s 1,800 frontline carrier aircraft in 1941 were divided into three types: dive-bombers, carrier attack planes (which could carry either bombs or a torpedo), and fighters. The dive-bomber was the Aichi D3A1 Type 99, nicknamed the “Val” by Allied naval intelligence.** A two-seat monoplane, with a pilot in front and a radioman/gunner in the rear seat, the Val carried one 250-kilogram (551-pound) bomb and two smaller (60 kg) bombs under the wings. It borrowed some design elements from Japan’s new ally, having an elliptical wing like the German Heinkel and fixed landing gear like the Stuka. It proved a very reliable weapon in China against ground targets and weak opposition, but its indifferent speed of 205 knots (242 mph) would make it vulnerable to American fighters in the war to come.
More impressive, and more central to Japanese doctrine, was the Nakajima B5N2 Type 97 carrier attack plane, which the Allies dubbed the “Kate.” The Kate could function as a level bomber, but it was deadliest when used as a torpedo plane. Indeed, it was very likely the best torpedo plane in the world. It had a crew of three and could handle a bomb load of over 800 kilograms (1,764 pounds), which meant that it could carry either a heavy fragmentation bomb for attacks against land targets or the new Type 91 aerial torpedo. Though the Americans had not used live torpedoes in peacetime training because of the expense, the Japanese did, and this led to improvements that paid off in wartime. The Type 91 torpedo boasted wooden tailfins that kept it stabilized during the air drop and then broke away when it hit the water. It traveled at a speed of 42 knots (nearly 10 knots faster than American torpedoes) and had great accuracy thanks to an internal gyroscope. The one weakness of the airplane that carried this powerful weapon was that, like most other Japanese combat airplanes, the Kate was mostly unarmored, so that while it packed an impressive offensive punch, even minor damage was often fatal.22
The Japanese B5N2 Type 97 carrier attack plane, called the “Kate” by the allies, was the best torpedo plane in the world in 1942, especially when carrying the big Type 91 aerial torpedo, seen here. (U.S. Naval Institute)
The third component of the Japanese carrier triad was the Mitsubishi A6M2 Type 00 fighter. Officially the Americans named this the “Zeke,” but nearly everyone called it by the name that is remembered by history: the Zero. This iconic airplane of the Pacific war came about because of Japan’s desire to provide bombers in China with long-range fighter support. In the fall of 1937, the Japanese set out to build a monoplane fighter with both longer range and heavier weapons. When it debuted in 1940, the Zero was a zippy little sports car of a fighter. It had not only a longer range than any other fighter—even land-based fighters—but it could climb faster and turn sharper. Moreover, in addition to its two machine guns, it carried two 20 mm cannon in the wings, which meant that like the Kate it packed a terrific offensive punch. One problem was that these cannon fired only sixty rounds before running out, making extended combat operations difficult unless the pilots hoarded their ammunition. On some occasions, the Zeros had to land to reload after a relatively short flight. And while the Zero had an impressive maximum speed of 287 knots (330 mph), its light airframe meant that it could not dive as fast as the sturdier American fighters; American pilots learned that the best way to escape a Zero on their tail was to dive straight down. Nonetheless, Japanese pilots reveled in the acrobatic abilities of their nimble little fighter plane, and early in the war they had an unmistakable advantage over their American counterparts, especially at low altitudes. But once again their lack of armor made them vulnerable. Like so many Japanese combat planes, the Zero was all offense and no defense.23
It is noteworthy that the men who flew these planes off the decks of Japanese carriers were mostly enlisted men—warrant officers and petty officers—and not commissioned officers, as was common in the U.S. Navy. This is especially curious because the Japanese Navy had a higher overall percentage of officers than the U.S. Navy. Yet until 1938, the number of graduates from the Japanese naval academy at Eta Jima who chose aviation was quite small. Pilots were thought of mainly as technicians, and such technical skill was held to be only marginally relevant to the burden of command. This changed after 1938. By then most Eta Jima graduates who were physically qualified were being reserved for aviation service. When war began in late 1941, these officers were still relatively junior, and, during the war, the Imperial Japanese Navy suffered a dearth of middle-grade officers—lieutenant commanders and commanders—who had both flight training and combat experience. The few who did became squadron commanders. Most of the pilots they commanded, however, were warrant officers or petty officers.24
For an enlisted sailor, there were two paths to becoming a carrier pilot. One was the Pilot Trainee System, in which petty officers or seamen under the age of 24 could apply for flight training. The acceptance rate was very small. As in the production of the airplanes themselves, the selection of young men for pilot training focused on ensuring quality rather than quantity. To those who ran the programs, it seemed more important to keep out the undeserving than to encourage the marginal. The historian John Lundstrom notes that for the class of 1937, of fifteen hundred applicants, only seventy were selected for training, and only twenty-five graduated.25
The other source of Navy pilots was the Flight Reserve Enlisted Trainee System. In the mid-1930s the Japanese concluded that taking sailors who were already trained in surface warfare and making pilots of them wasted valuable training. As a result they began to draw aviation candidates directly from civilian life, often teenagers from the equivalent of junior high or high school. In addition to flight training, these candidates got three years of classroom education, so that their experience resembled that of students at Eta Jima, though they graduated as petty officers rather than as commissioned officers. Moreover, their numbers remained small. As in the Pilot Trainee Program, until 1938 the Japanese focused on making flight training as fierce as possible in order to wash out marginal performers. Pilots trained in small classes of only four men each. After 1941, with war looming, instructors were allowed to teach eight at a time, and by 1943 they were teaching twelve. By then, however, it was too late to make up for lost time. By then, too, many of the best instructors were either at sea operating with the carriers or had already been lost in combat. The result was that while Japan began the war with a cadre of very highly skilled and intensively trained pilots, there was no established program to add large numbers of new pilots to the fleet as the war went on. In part this was another result of the commitment to quality over quantity, and it was also the product of the Japanese assumption that the war with the United States would not last very long. That assumption led to the conclusion that it was more important to have this cadre of highly skilled pilots at the outset than to have large numbers of indifferent pilots for the long run. When the war began, the Japanese had a total of about 3,500 superbly trained and experienced naval aviators, about 90 percent of them enlisted men. (The American pool of aviators was larger, but many of them were still in training programs, and none had the combat experience of their Japanese counterparts.) The Japanese thus bet on quality triumphing over quantity, but they also gambled that the war would be a short one, for they had very little in reserve.26
This, then, was the Kidō Butai: the ships, the planes, and the pilots that struck at Pearl Harbor on December 7, 1941. Th
roughout the country, the Japanese celebrated the apparent success of that raid, though Yamamoto was disappointed that Nagumo had been content to hit and run instead of “completely destroying Pearl Harbor.” Not only had the attack missed the American carriers, it had left untouched the American submarine base and especially the oil-tank farm—valuable resources that the Americans would have found it difficult to replace—though such targets were not part of Nagumo’s initial assignment. Despite misgivings about him, Nagumo remained in command of the Kidō Butai because, as Ugaki put it, “the navy had no other adequate candidate.”27
During the four months after Pearl Harbor, the Kidō Butai burnished its reputation further, as those months witnessed a dizzying string of Japanese successes that fed what historians later labeled “victory disease” in Japan, and caused lots of hand-wringing in Washington. And it was not just the Kidō Butai. Perhaps the most chilling event of this period for the Allies was the loss of the Royal Navy battleship Prince of Wales, just arrived in the Far East after a lengthy high-speed cruise from the Atlantic, and her consort, the battle cruiser Repulse, both sunk on December 10 by land-based Japanese bombers staged out of Indochina. Though Japanese carrier bombers and torpedo planes had sunk or damaged eight U.S. battleships in Pearl Harbor, those ships had been at anchor. The sinking of the Prince of Wales and Repulse while they were alert, manned, and under way was proof that airplanes could indeed sink battleships.28
The Battle of Midway (Pivotal Moments in American History) Page 5