The Last Bid for a “Decisive Battle”

Ozawa was a career naval officer shaped by earlier victories. As a young man, he had grown up in a navy that worshiped the memory of the Battle of Tsushima, where Japan’s fleet had defeated Russia in 1905. From that triumph came a core belief: a single, concentrated engagement at sea—a “decisive battle”—could reset the balance of power.

That belief had seemed justified in the early years of the conflict. Carrier strikes had stunned opponents at places like Pearl Harbor and in Southeast Asia. Japan’s doctrine assumed that skill, coordination, and courage, concentrated in one powerful blow, could overcome even a larger enemy.

But by June 1944, the strategic picture had changed dramatically.

Across the Pacific, the United States had been advancing steadily, island by island, building airfields, expanding naval bases, and pushing carrier task forces ever closer to Japan’s defensive perimeter. American industry was in full motion. Shipyards were launching new carriers and escorts in rapid succession. Factories were turning out aircraft by the thousands. Training centers were producing not just pilots, but an entire ecosystem of specialists—mechanics, radar operators, gunnery crews, planners.

Ozawa understood the numbers were not in his favor. He knew he faced a foe with more ships, more planes, and deeper reserves.

But he still believed in one thing: that a well-timed, concentrated strike on the enemy’s carriers could alter the tide.

A Fleet of Carriers—and a Shortage of Experience

On paper, the Mobile Fleet looked formidable. Taihō, Shōkaku, Zuikaku, and others formed a powerful group. But the strength of a carrier arm rested not only in its decks and machinery, but in its aircrews.

Here, the cracks were deep.

Before the conflict, Japan had trained naval aviators in small, elite classes. Pilots received hundreds of hours of flight time before joining frontline units. The early-war carrier raids had been flown by professionals who could navigate long distances over open ocean, land on pitching decks, and coordinate complex attacks.

Most of those veterans were gone by 1944, lost in earlier battles and unable to be replaced at the speed the war demanded.

Fuel shortages and resource constraints had forced Japan to shorten training programs. Many of the pilots under Ozawa’s command had roughly 100 hours of flight time—a fraction of what their predecessors had received. By comparison, American naval aviators were entering combat with around 600 hours in the air, supported by dedicated training carriers and live-fire ranges that consumed vast amounts of fuel and ammunition.

The Japanese fleet still had carriers. It still had aircraft. It still had brave pilots.

What it no longer had was a sustainable system to create experienced aircrews at scale.

An Invisible Opponent: Radar, Direction Centers, and Technology

The greatest advantage Ozawa did not fully see was not a ship or an aircraft, but an invisible network.

By 1944, U.S. carrier task forces were protected not only by fighters and surface guns, but by:

Long-range radar, capable of detecting incoming formations over 100 miles away.

Fighter direction centers, where officers used radar data to calculate interception courses.

Modern fighters like the Grumman F6F Hellcat, built for speed, durability, and firepower.

Proximity-fused anti-aircraft shells, which could detonate near an aircraft rather than requiring a direct hit.

From the bridge of Taihō, Ozawa saw clear skies and an open horizon. What he could not see was that as soon as his first wave of aircraft took off, they were being tracked, plotted, and prepared for.

Launching the Strike

At 0730 hours, Ozawa gave the order.

The first wave—about 70 aircraft from Taihō, Shōkaku, and Zuikaku—rose from their decks. Fighters, dive bombers, and torpedo planes circled once, formed up, and headed east toward the American fleet. Over the course of the day, Ozawa would send out four strike waves, eventually launching 373 aircraft.

His staff had carefully calculated the timing. Based on range and flight speed, he expected first contact with the American carriers mid-morning and, if things went well, early reports of hits and fires shortly afterward.

Instead, the first responses that reached Taihō were confused fragments.

Messages referencing “heavy opposition.”
Reports of scattered formations.
And then, gradually, nothing at all.

A Sky Turned into a Trap

What happened to Ozawa’s aircrews became clear only later.

American radar screens had picked up the first incoming wave at long range. Fighter direction officers aboard carriers like USS Lexington calculated intercept points and vectored groups of Hellcats into position.

By the time the Japanese formations approached within striking distance of the American carriers, they were met by hundreds of U.S. fighters, layered at different altitudes, waiting at precisely the points radar predicted they would pass through.

The battle was fierce but extremely one-sided. Many Japanese pilots never saw their attackers before their aircraft were hit. Others were forced to break formation, losing the concentration needed for effective bombing or torpedo runs. Anti-aircraft fire, guided by radar and enhanced by proximity fuzes, added another deadly barrier between them and their targets.

Time and again, Japanese formations were engaged far from their objective, often 50–60 miles out, long before they could threaten the American carriers themselves.

When the surviving aircraft finally limped back to their own decks, the accounts they brought with them painted a picture of a sky filled with defending fighters and dense defensive fire.

The Numbers Tell the Story

On Taihō’s plotting tables, staff officers began tallying the outcome:

First wave: 69 aircraft launched, about 24 returned.

Second wave: 107 launched, fewer than 40 made it back.

Third wave: 47 launched, only 7 returned.

Fourth wave: 82 launched, 9 returned.

By day’s end, of the 373 aircraft sent into action, roughly 130 came home.

Japan had lost 243 carrier aircraft in a single day, with no confirmed sinkings of American carriers and only minor damage inflicted on a single battleship.

For the Mobile Fleet, this was not just a bad day—it was a strategic disaster.

Submarines in the Shadows: The Loss of Taihō and Shōkaku

Even as Ozawa was grappling with the loss of his air groups, another threat was moving silently below the surface.

Early that morning, the U.S. submarine USS Albacore had maneuvered into position and fired a spread of torpedoes at Taihō, the newest and most advanced carrier in the Japanese fleet. Most of the torpedoes missed. One did not.

The hit damaged aviation fuel systems deep within the ship. At first, the situation appeared serious but manageable. Damage-control teams, however, made a critical mistake: in trying to clear fuel vapors, they increased ventilation, inadvertently spreading flammable fumes throughout the interior.

For hours, Taihō operated as a functioning carrier while, unseen, an invisible cloud of vapor turned her into a floating risk. In mid-afternoon, the fumes found an ignition source. The resulting internal explosion was catastrophic. The ship’s structure failed, and Taihō rolled and sank, taking roughly 1,600 crew with her.

Around the same time, another U.S. submarine, USS Cavalla, struck the veteran carrier Shōkaku with multiple torpedoes. Fires spread through her hangars, igniting fuel and munitions. By early afternoon, Shōkaku was gone.

In a matter of hours, Japan had lost two major carriers—not to air attack, but to undersea strikes.

The American Counterblow

On June 20, as Ozawa’s surviving ships retreated westward, American search planes finally located the fleeing fleet. The distance was extreme, the timing tight, and the risks high. Pilots would have to launch late in the day, strike near sunset, then attempt to return over open water in darkness with very limited fuel.

Standard practice advised against such an operation.

Admiral Marc Mitscher, commanding the American carrier task force, chose to proceed.

He ordered a large strike launched despite the risk. The attacking force damaged several Japanese ships and fatally hit the carrier Hiyō, further eroding what remained of Japan’s ability to conduct carrier operations.

On the return flight, many American pilots found themselves lost or low on fuel in the night sky. In a decision that became famous in naval history, Mitscher ordered his ships to switch on their lights—floodlights, signal lamps, even star shells—to guide the aviators home, despite the risk of revealing the fleet’s position.

Dozens of aircraft were still lost due to fuel exhaustion or night landings, but many aircrews were saved. Critically, the United States could replace both the aircraft and most of the equipment lost. The pilots, too, were part of a system built to regenerate manpower and machines.

Japan no longer had that margin.

Courage Against a System

By the time reports were consolidated, Japanese records showed:

476 aircraft lost (including carrier- and land-based planes),

Three fleet carriers sunk (Taihō, Shōkaku, and later Hiyō),

No American carriers sunk and only limited damage inflicted.

The Battle of the Philippine Sea became one of the most one-sided naval-air engagements in history.

Ozawa understood something essential about that defeat. His pilots had flown bravely. His ships had fought as best they could. His staff had followed doctrine and calculations.

But they were no longer facing a single enemy fleet—they were facing an entire industrial and training system:

A system that produced aviators faster than Japan could train them.
That built radar sets, aircraft, and ships in quantities Japan could not match.
That could afford to take risks, replace losses, and return to battle with fresh strength.

After the Philippine Sea, Japanese carriers would sail again, but their decks were often thinly populated. Many surviving aircrews were reassigned to land bases for desperate special missions as the conflict approached its closing chapters.

Vice Admiral Ozawa survived the war and lived long enough to see his country rebuild in a very different form. He rarely spoke publicly about the battle. Yet the story of June 19–20, 1944, stands as a stark illustration of a central truth of modern conflict:

Individual courage, no matter how great, cannot by itself overcome a well-organized, well-supplied system built for endurance.

On that June morning, Ozawa launched 373 aircraft into the eastern sky. By sunset, only about 130 returned—and with them, the era of Japan’s carrier air power effectively came to an end.