Many years ago, while on a summer tour of the Caroline Islands for research on a book on the rise and passing of the Japanese in Micronesia, I thought I heard the roar of fighter engines. On the high island of Ponape, I was driving along, looking for what I had been told had been one of the Japanese navy’s two air bases on the island. It was high noon, incredibly hot and still, as I slowed the car near where I had been told I should find the airfield or what was left of it. Across the taro patches and through clusters of trees I saw the ribs of what I took to be a ruined aircraft hangar. After a rough and prickly trek through the weeds, I came upon the foundations of what must have been a barracks, some small construction locomotives, trenches, concrete bunkers, and other detritus of war.

I knew that fighter planes had been based on the island during the Pacific War. Indeed, during the course of the hour or more I spent at the site, I stumbled across the twisted remains of a Mitsubishi Zero more than a hundred meters from one of the airfield’s runways. Vines and grasses had pulled a shroud over the wrecked fuselage, and only the tail section, broken off from the fuselage, remained uncovered. I walked back to the airfield. All was heat and sun and somnolence. I looked out across the broad expanse of weeds and grass that had once been the runway, trying to make out the faded markings on fuselage and tail assemblies, wondering what the Zero must have looked like when, with its fellows, in full fighting trim and still bravely bearing its air group and pilot markings, it had touched down on this remote tropical airfield with the same airy lightness it would have brought to the flight deck of a carrier.

As I strained to imagine what must have been here, I began to catch the cough, the choke, and then the roar of engines as the fighters sped down the runway and lifted off to hurl themselves against the waves of the approaching aerial enemy. What had it been like at this air base during those desperate months when the Japanese navy sent its men and planes to defend outlying defenses such as this, only to have them consumed in the furnace of American air power like moths drawn to a candle? How had Japanese naval air power, which had been so dazzling and seemed so invincible following its epic victory at Pearl Harbor, been so utterly destroyed as a fighting force?

There are many reasons for the catastrophic collapse, but a few general categories stand out: first, the navy’s failure to anticipate the kind of air combat it would be obliged to wage; second, once in the new kind of air war, failing to make the right decisions to deal with its realities; and third, the inability of Japanese industry and technology to support Japanese naval aviation against the emerging numerical and qualitative superiority of American air power.

Strategic and Logistical Failures

In prewar Japanese strategic-planning documents we find numerous references to the necessity to prepare for a war of attrition against the United States. The Japanese assumed that their lightning conquests in Southeast Asia and in the Southwest Pacific would enable them to build a defensive ring of naval and air bases around their conquered sphere. Further, they assumed that ships and aircraft along this defensive barrier would wear down American offensives against it by ceaseless counterattacks. The Japanese counted on this strategy to lead to a stalemate and, ultimately, to a negotiated settlement that would end the war in Japan’s favor. But the Japanese navy’s strategy to wage such a war was based on a disregard of the fundamental reality of the Pacific.

The Japanese navy’s plans called for creating a great chain of island air bases that would form a defensive barrier around Japan’s conquests in the central and southwestern Pacific, forestalling any American counteroffensives to retake them. Shifting the navy’s long-range bombers from one to another of these “unsinkable carriers,” as Admiral Yamamoto viewed the island bases, the navy believed that it could launch preemptive attacks against any enemy advance. Here, the navy clearly misjudged the vast distances over which it would have to fight. The distances between Japanese bases throughout the western and southwestern Pacific proved too great even for the longest reach of its land-based aircraft; it thus proved impossible to provide the flexible defense that Yamamoto had envisioned. And thus, one by one, without substantial help from the nearest air garrisons, the navy’s air bases fell before the American amphibious tidal wave.

Worse still for the Japanese navy, in the Pacific War it was the United States that forced the pace of attrition of Japanese ships and aircraft by repeatedly opening offensive operations before the Japanese naval high command expected them and before Japanese frontline commanders had the chance to recover from their most recent defeats.

The unrealistic quality of the navy’s plans for winning an extended war is also apparent in its personnel policies and aircraft design priorities. The creation of a small but elite pool of naval aviators with no substantial reserve to back it up, or any training program in place with which to do so, speaks of the mistaken assumption of a short, victorious conflict. That assumption is confirmed by the design and production of aircraft that provided scant means to protect the personnel who flew and fought in them and thus did nothing to preserve that precious elite once the air war of attrition began.

The consequences were ultimately fatal. Once the navy recognized that it was far better to have lots of competent pilots than a handful of outstanding ones, it was too late. The terrible shredding in combat of the navy’s top air units, the ever-increasing need for their replacement, and the decreasing time and fuel available for adequate training to provide such replacements had by midwar already left the navy with only the greenest trainees, who were quickly sacrificed in the fire of combat.

American air personnel policies before and during the Pacific War stood in sharp contrast. The American emphasis on training far greater numbers of aviators (albeit at somewhat lower standards of performance), the assignment of training units aboard aircraft carriers, and the provision of aircraft that offered aircrews greater lifesaving protection gave American aviators an overwhelming advantage in air combat by very early in the war. In sum, as Fuchida Mitsuo and Okumiya Masatake concluded in their account of the Battle of Midway, the Japanese naval air service “failed to realize that aerial warfare is a battle of attrition and that a strictly limited number of even the most skillful pilots could not possibly win out over an unlimited number of able pilots.”

Compounding the growing shortage of trained pilots (and ground crews) was the matter of supply and maintenance. The vast distances involved in the Pacific War affected the ability of both sides to adequately supply their naval air forces, but the Japanese were especially at the mercy of their long and unreliable chain of supply. As the war progressed, they became alarmingly and increasingly short of replacement aircraft, spare parts, ordnance, and fuel. For example, such was the shortage of aviation fuel late in the war that the navy began investigating the possibility of extracting aviation fuel from pine roots! Simply put, the Japanese naval air arm lost the decisive battle of supply and maintenance to the Americans.

Failure to Adjust

If the catalog of failures to anticipate the nature of an air war in the Pacific was fundamental to the navy’s defeat in that conflict, so too were the collective demonstrations of the navy’s inability or unwillingness to make the necessary changes once the war began. The first of these changes should have been recognition, at the very top of the naval high command, that the first six months—indeed, the first month—of the Pacific War had proven beyond doubt the dominance of air power over the big-gun capital ship. Such a clear-headed recognition should have resulted in an early decision to abandon the concept of the great and supposedly decisive gun duel at sea and, flowing from that decision, a decisive step to reorder the basic force structure of the Japanese navy.

In a thunderclap, the Japanese navy itself had brought such a realization and such a decision to the U.S. Navy in the opening hours of the war. At Pearl Harbor the obsolescent American battle line had been critically disabled, thus freeing the U.S. Navy from its reliance on the capital ship and from whatever lingering faith it might have had in its preeminence. Air power, both land- and carrier-based, became the focus of innovative American tactical thinking and the recipient of a major portion of American industrial output.

In contrast, the Japanese navy was slow to give up its prewar big-gun/big-ship convictions. On the eve of the Pacific War, with the great increase in the performance of aircraft, air power advocates in the Japanese navy argued that aviation was now the dominant arm in naval warfare, and in the first few months of the conflict it was air power that scored the most dramatic and crushing victories. To be fair, this failure to act on the realities of the air power revolution stemmed from the fact that it was beyond the nation’s industrial capacity to produce adequate numbers of both warships and aircraft. One can argue with 20-20 hindsight that a bold decision should have been made to limit warship construction severely and go flat out for air power, particularly the production of heavy land-based bombers. But because ships were also badly needed, this proved impossible.

The grip of the big-gun/big-ship orthodoxy on Japanese naval thinking far into the Pacific conflict had another unfortunate consequence: the failure to give airmen substantial authority over the strategy and conduct of the navy’s air war. Throughout the war most of the navy’s decisions concerning air operations were made by men whose experience and viewpoint had to do with capital ships, not with air power. Japanese naval aviators may have brought their own prejudices and misconceptions to the air war, but they were infinitely more aware of the realities of aerial combat than the naval brass in Tokyo—mostly trained in surface warfare—who directed the air strategy from afar.

Industrial and Technological Weakness

Finally, the fiery descent of Japanese naval air power in the Pacific War can be attributed to the discrepancies in strength and versatility between American and Japanese industry. There was a tremendous surge in the Japanese navy’s air arm in the years immediately prior to the Pacific War. In that period, the technical skills of its aircrews and the quality of its aircraft and weapons rapidly became among the best in the world. But the navy’s leadership decided on war without adequate forethought as to the prospects of fighting a long war with an enemy so superior in industrial, scientific, and technological resources. Consider just three examples of how this gap adversely affected Japanese naval air power: radar, the VT fuze, and aircraft engine design.

Radar was the single most important technological advantage held by the U.S. Navy in the Pacific War. Its applications were numerous, of course, but in the naval air war, in combination with the installation of the combat information center about U.S. warships (an area on a warship where electronic information on movements of aircraft and surface vessels was collected and plotted), it enormously strengthened the air defenses of Allied fleet units, particularly in vectoring combat air patrols toward inbound Japanese air strikes. Conversely, by the end of the war, radar sets installed in U.S. naval aircraft helped their pilots identify and attack Japanese air and surface targets. In contrast, advances in shipborne and airborne radar lagged in the Japanese navy for a variety of reasons.

The VT, or proximity, fuze was another Allied technological advance that helped break the back of Japanese naval air power. Antiaircraft fire was a great killer of aircraft on both sides during the Pacific War, but American antiaircraft fire was particularly dangerous to Japanese fighters and bombers because of their fragile construction. Then in 1943 the appearance of the American proximity fuze changed antiaircraft defenses from dangerous to deadly. The mechanism enormously enhanced the antiaircraft fire of American warships, since their shells no longer needed actually to hit approaching Japanese aircraft, only to come within specific proximity of their targets for their radio devices to detonate the projectiles. Together with radar and the inexperience of Japanese naval aircrews during the same period, this lethal weapon shredded Japanese air attack forces.

The third example centers on the design of American aircraft engines, whose performance stood in sharp contrast to Japanese wartime power plants. From the beginning of the Pacific War, the design staffs of the huge American aircraft industry, in close cooperation with the American military services, were continually engaged in designing and constructing the best lines of aircraft and aircraft engines to meet the wide diversity of combat needs and changing wartime requirements of the services. In particular, the progress of American manufacturers in the continual improvement of aircraft engines put them well ahead of their counterparts anywhere else on the globe. In this effort, they were able to call on the expertise and services of America’s wide network of laboratories and research centers and also upon the abundant natural resources of the country, including the broad range of raw materials for engine parts. Favored by these advantages, the United States was able to produce the world’s lightest and most powerful engines, eventually improved even further by turbo-superchargers. This availability of greater engine power in a lighter “package” meant that aircraft designers had a greater range of options and opportunities. In turn, this meant that aircraft of ever-increasing engine power, range, and performance—the Hellcat, the Lightning, the Corsair—became available in awesome numbers on the decks of American carriers and on the runways of advance bases in the Pacific.

In contrast, the Mitsubishi Zero reflected the limitations of the Japa-nese aircraft industry. It was a fighter plane of outstanding performance, yet the aircraft suffered from a series of ultimately fatal weaknesses, at least half of which were due to its small engine. In the later stages of the Pacific War this discrepancy was to prove a fatal weakness in encounters between Japanese and American fighter aircraft. By the summer of 1943, the Allies’ combination of new tactics and new and more powerful aircraft had begun to drive the once-dreaded Zero from the skies. The Japanese navy (as well as the army) developed better fighter aircraft, of course, but these were produced in far smaller numbers; and the navy continued to rely mainly on the Zero up to the end of the war. That it was obliged to do so speaks volumes for the limited manpower base of Japanese engineering, which took twice as long to develop a new airplane as its American counterpart.

By midwar, all these elements of American material superiority—industrial, technological, and logistical—combined with American innovative and organizational skills, ultimately sent Japanese naval air power to fiery destruction.

In the end the Japanese naval air service was outproduced, outorganized, outmanned, and outfought. But for a brief time its combat performance in an age of industrial war had been dazzling. In that conflict its Zero fighter, dainty as a dragonfly and dangerous as a rapier, was to prove the transcendent symbol of the amazing qualities and fatal weaknesses of Japanese naval air power. Dazzling in its quickness, extraordinary in its reach, and possessed of great firepower, its vulnerabilities in design—poor diving speed, poor handling capabilities at high altitude—and frailties in construction—too many possible failure points and lack of protective armor for their pilots and fuel tanks—were ultimately discovered and exploited by its foes. Collectively, moreover, its assets embodied the central assumption with which the Imperial Japanese Navy went to war: that speed, maneuverability, and firepower would deliver a slashing stroke at the outset and would bring the giant to its knees before it could assert its massive strength. Ultimately, the most critical failure of Japanese naval air power was the failure of the navy’s leaders, before the war ever began, to conceive the possibility that the initial stroke would not be mortal to the enemy or that, given time and superior strength, that enemy would be able to apply his death grip.

There are not many Zero fighters left today. A few still rust away amid the jungles and weeds on islands in the tropical Pacific. Fewer still, beautifully restored and maintained, grace the floors of air museums in Japan and the United States, even today an object of admiration and awe to those who view them. For if they never could have provided the margin of victory for the nation and the navy in the Pacific War, the precision, the skill, and the technical mastery with which they were created lived on and gave wings to the phoenix of postwar Japanese technology.

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