Japan Shocked by Armored Flight Decks at Okinawa

Japan Shocked by Armored Flight Decks at Okinawa

The spring of 1945 was the final violent season of a war that had consumed the world. In Europe, the great Allied armies were closing on Berlin. But in the Pacific, the end was not yet in sight. The ocean had become the proving ground for a new kind of warfare. A conflict fought not with the thunder of broadsides, but with the scream of diving aircraft.

 The battleship, for centuries, the undisputed monarch of the seas, had been dethroned. The aircraft carrier was the new queen, the steel heart of naval power, and the war had become a contest of floating airfields. Off the coast of Okinawa, the largest and most powerful naval force ever assembled gathered for the last great amphibious assault of World War II.

Designated Operation Iceberg, the invasion brought together the two great Allied navies. the United States Navy, whose industrial might had built a fleet of unprecedented size and power, and the Royal Navy, a force forged in the bitter close quarters battles of the Atlantic and Mediterranean.

 They were united in purpose, but their primary weapons, the fleet aircraft carriers that formed the core of their respective task forces, were born of profoundly different philosophies. The American Essexclass carriers of Task Force 58 were instruments of overwhelming offense designed to project power across the vast distances of the Pacific and annihilate the enemy.

 The British illustrious class carriers of Task Force 57 were floating fortresses designed to absorb punishment and endure. This fundamental divergence in design, a direct result of different strategic realities and experiences of war, was about to be tested in the most brutal way imaginable. A new weapon born of desperation and a marshall code that glorified self-sacrifice was about to be unleashed.

 Japan, its conventional military power shattered, was preparing to meet the Allied Armada with a divine wind, a storm of human-guided missiles called the kamicazi. The ensuing trial by fire would render a bloody and decisive verdict on which design philosophy would prevail against this unforeseen terror. The design of the Royal Navy’s fleet carriers was a direct reflection of their expected operating environment.

 Constrained by the Second London Naval Treaty, which limited carrier displacement to 23,000 tons, British naval architects were forced into a series of critical compromises. Their primary concern was the constant threat of landbased air power. Having fought for years against the German Luftwafa and Italian Reia Aeronautica in the narrow lethal confines of the Mediterranean, the Admiral T prioritized survivability above all else.

 The result was the illustrious class, a revolutionary design centered on an integrated armored box. This was not merely a ship with armor plating added. The armor was a fundamental part of the vessel structure. The flight deck itself, a 3-in thick layer of steel, served as the roof of this box and was the ship’s main strength deck.

 The hanger floor was another 3-in armored deck, and the sides were protected by 45 in of armor plate. This armored citadel was designed to withstand hits from 1,000lb bombs, sealing the ship’s vitals, its aircraft, aviation fuel, and magazines inside a protective cocoon. This level of protection, however, came at a steep price.

 The immense weight of the armor, particularly the topside flight deck, necessitated a smaller hanger to maintain stability. Consequently, an illustrious class carrier like HMS Formidable could operate a maximum of around 54 aircraft, a fraction of what its American counterpart could field. Aviation gasoline storage was similarly limited, restricting the carrier’s ability to sustain high tempmpo flight operations.

The Royal Navy had made a conscious choice, sacrificing offensive striking power for defensive resilience. They had built a ship designed to take a punch. The United States Navy, unburdened by treaty limitations, pursued a different doctrine entirely. Their strategic calculus was dominated by the immense distances of the Pacific Ocean and the need to project overwhelming force.

 The Essexclass carrier was the ultimate expression of this philosophy. a weapon system optimized for the deck load strike, the ability to launch a massive wave of aircraft in a single decisive blow. To achieve this, every aspect of the design prioritized defensive capability. The flight deck of an Essex class ship like the USS Bunker Hill was unarmored, constructed of thin steel plate covered with wooden planking.

 This lightweight construction allowed for a larger, higher flight deck and a capacious open-sided hanger bay below. This open hanger design was a key feature, improving ventilation to disperse dangerous gasoline fumes and allowing aircraft engines to be warmed up below decks, which significantly reduced launch times.

 The American doctrine held that a wooden flight deck was more easily repaired at sea than a damaged armored deck, allowing the carrier to return to the fight more quickly. protection was concentrated lower in the hull with an armored hanger deck and a second armored deck further below intended to contain any explosions that penetrated the flight deck.

 The result of this design was a carrier that could operate an air group of up to 100 aircraft nearly double that of a British carrier and carry vast stores of fuel and munitions. The Essex class was not built to absorb damage. It was built to inflict it, to destroy the enemy before he could strike back.

 At Okinawa, this theory of active overwhelming defense would be put to the ultimate test. By late 1944, Japan was facing total defeat. Its navy had been shattered at the Battle of Ley Gulf, and its air forces had been decimated in a long war of attrition. The nation’s industrial capacity could not hope to match the torrent of ships and aircraft pouring out of American shipyards and factories.

 In this atmosphere of desperation, Vice Admiral Takajiro Anishi conceived of a new terrifying tactic. He argued that the only way to inflict meaningful damage on the Allied fleets was through deliberate suicide attacks. These special attack units or Takotai were given the name Shinpu, the characters of which could also be read as kamicazi, the divine wind that had saved Japan from a Mongol invasion fleet centuries before.

 The kamicazi was a calculated military strategy. Japanese planners knew that conventional attacks by their inexperienced pilots against the formidable defenses of an Allied task force were feudal. A suicide attack, however, turned the pilot into a human-guided missile. able to make corrections up to the moment of impact and dramatically increasing the probability of a hit.

 The psychological effect on Allied sailors was a key part of the strategy intended to break their will to fight. The first official kamicazi attacks at Ley Gulf proved the tactics horrifying potential, sinking the escort carrier USS St. Low. for the invasion of Okinawa. This desperate gambit would be unleashed on a massive scale in a series of 10 great waves known as Kikusui or floating chrysanthemum.

 The allied fleets face two primary kamicazi weapons. The most common was a conventional aircraft, typically the Mitsubishi A6M0 fighter modified to carry a 250 kg bomb. Once the world’s most advanced carrier fighter, the Zero was by 1945 outclassed by American aircraft like the F-6F Hellcat. But its excellent maneuverability made it a suitable platform for the suicide mission.

 The pilots would often use cloud cover to approach before plunging in a steep dive, aiming for the most vulnerable part of a carrier, the flight deck and island superructure. A far more specialized weapon was the Yokosa MXY7 Oka or Cherry Blossom dubbed the Baka Bomb by the Allies. The Oka was a purpose-built human-guided missile.

 It was a small wooden glider packed with a massive 1,200 kg warhead carried to the target area slung beneath a Mitsubishi G4M Betty bomber. Once released, the pilot would glide towards his target before igniting three solid fuel rocket motors for a terminal dive at speeds exceeding 575 mph, making it nearly impossible to shoot down.

 The Oka’s critical weakness was its delivery system. The Betty bombers were slow and vulnerable, and most were shot down by the American combat air patrols long before they could get within range of the fleet. The pilots of these weapons were not mindless fanatics. Many were university students driven by a complex mix of cultural duty and national desperation.

 Ensign Koshi Ogawa, a 22-year-old graduate of Wazida University, volunteered for the special attack force. In a final letter home, he wrote, “I will make a sorty flying over those calm clouds in a peaceful emotion. I can think about neither life nor death. I will go to the front smiling on the morning of May 11th, 1945.” Ogawa and his squadron leader, Sub Lieutenant Cizo Yasunori, would take off on their final mission.

 Their target, the flagship of the American Fast Carrier Task Force, USS Bunker Hill. The main striking force of the Allied fleet at Okinawa was the US Fifth Fleet Task Force 58, commanded by Vice Admiral Mark Pete Mitcher, comprising 17 American carriers. Its mission was to provide air support for the invasion and fend off the main Japanese counterattacks.

Operating on the southern flank was the British Pacific Fleet designated task force 57 commanded by Vice Admiral Sir Bernard Rawlings. Its four armored carriers were tasked with neutralizing Japanese airfields on the Sakiishima Ganto Islands, preventing them from being used as staging bases for attacks on the main fleet.

 This division of labor meant that the American carriers of TF58 would bear the full brunt of the mass Kikusui attacks launched from the Japanese home islands while the British of TF57 would face smaller, less coordinated raids. The resilience of the British armored carriers quickly became the stuff of legend.

 On the morning of May 4th, 1945, HMS Formidable was operating off the Sakushima Gunto when a Lone Zero plunged out of the clouds. Despite being hit by anti-aircraft fire, the pilot pressed his attack, slamming into the flight deck near the island. The impact and the detonation of his 550lb bomb gouged a massive 2-ft deep crater in the 3-in armored deck, but it did not penetrate.

The armored box held. A fire raged among the parked aircraft on the flight deck. But because the hanger below was a sealed protected space, the flames could not spread to the fuel and munitions stored within. Damage control parties fighting the blaze from the gallery decks. Had the fires extinguished in under 25 minutes.

 Eight men were killed and 47 wounded. Astonishingly, the crew immediately set to work filling the crater with quick drying cement and welding a steel plate over the top. By 5:00 p.m. that same day, less than 6 hours after being hit, HMS Formidable was landing aircraft and fully operational again. 5 days later, on May 9th, it happened again.

 Another kamicazi slipped through the combat air patrol and Dove on the British fleet. After fainting towards HMS Indomitable, it turned and slammed into Formidable’s aft deck park. The 500lb bomb detonated, depressing the flight deck armor by 45 in. But once again, it failed to penetrate. A single rivet was blown out, allowing some burning fuel to spill into the hanger.

 But the sprinkler system immediately activated and extinguished the small fire. On the flight deck, another intense fire destroyed seven aircraft. One man was killed, drawing on their recent hard one experience. The crew had all fires out within 15 minutes. 50 minutes after the impact, the carrier was once again fully operational.

 The armored deck had proven its worth beyond any doubt, giving rise to the famous, if possibly apocryphal, remark from a US Navy liaison officer. When a kamicazi hits a US carrier, it means 6 months of repair at Pearl. When a kamicazi hits a limey carrier, it’s just a case of sweepers. Man, your brooms.

 The grim truth of that statement was about to be demonstrated with devastating clarity. On the morning of May 11th, 1945, just two days after the second attack on Formidable, Task Force 58 was operating east of Okinawa. Its flagship USS Bunker Hill had been in continuous combat for 58 days. At 10:04 a.m., with the crew at a lower state of readiness, two zeros piloted by Sublieant Cizo Yasunori and Ensign Koshi Ogawa emerged from the clouds and began their attack dives.

 The assault was terrifyingly swift. Yasunori Zero screamed down, his 550lb bomb piercing the thin wooden flight deck, passing through the gallery deck, and exiting the side of the ship before exploding in the ocean. The plane itself, however, slammed into the 34 fully fueled and armed aircraft parked on the flight deck, creating a massive fireball as thousands of gallons of aviation fuel ignited.

 30 seconds later, as chaos engulfed the aft deck, Ogawa began his run. He braved a storm of anti-aircraft fire. His own 550lb bomb tearing through the wooden deck and detonating inside the ship in the gallery deck area that housed the pilot’s ready rooms. The explosion instantly killed 22 pilots of Fighter Squadron VF84. Ogawa’s plane then crashed into the flight deck at the base of the island, narrowly missing Admiral Mitcher, but killing 14 members of his staff.

 The result was an inferno. The unarmored open-sided hanger, a key feature of the American design for operational efficiency, now became a fatal flaw. It acted as a giant chimney, feeding the fires with oxygen and channeling them through the heart of the ship. A chain reaction of secondary explosions ripped through the vessel as parked aircraft, bombs, and ammunition cooked off.

 A correspondent on the nearby USS Enterprise described the scene as looking like the crater of a volcano. The crew’s damage control efforts were heroic. The ship’s captain, George Sites, ordered a hard turn that sent tons of burning gasoline sliding off the flight deck into the sea. In the smoke filled engineering spaces below, the chief engineer, Lieutenant Commander Joseph Carmichael, ordered his men to remain at their stations to maintain power and water pressure for the fire hoses. A decision that saved the ship,

but cost the lives of 125 of his men. Ray Rivera, a 17-year-old sailor, was on his way to the galley when the first plane hit and was immediately thrown into the desperate fight to save his ship. By late afternoon, with assistance from other ships, the fires were finally brought under control.

 But the cost was staggering. USS Bunker Hill suffered 393 men killed or missing and 264 wounded, the second highest casualty toll for any US carrier to survive the war. The following day, the crew conducted the longest burial at sea ceremony in US Navy history, committing 352 of their shipmates to the deep in a service that lasted nearly 8 hours.

 The flagship was knocked out of the war, forced to limp back to the United States for repairs that would not be completed until after Japan’s surrender. The difference in outcomes was stark. The British armored box had contained the fires to the flight deck, allowing damage control teams to fight them effectively. On Bunker Hill, the fire started inside the ship’s operational center, and the open hanger allowed it to spread catastrophically.

 The British design, conceived to defend against conventional bombs, had proven to be an almost perfect counter to the unique threat of the kamicazi. The verdict from Okinawa was clear. Against the specific threat of the kamicazi, the armored flight deck was an unqualified tactical success. It saved ships, it saved lives, and it allowed the carriers of Task Force 57 to remain in the fight.

 A United States Pacific Fleet report from May 1945 concluded bluntly that without their armored decks, the four British carriers of TF-57 would have been out of action for at least 2 months. However, to declare the British design superior overall is to ignore the strategic trade-offs. The very armor that made the illustrious class so resilient also limited its offensive power.

 An Essexclass carrier’s air group of nearly 100 aircraft gave it a vastly superior striking capability and critically a more robust combat air patrol. A stronger CAP meant more kamicazis were shot down far from the fleet before they ever had a chance to test a ship’s armor. It took roughly two British carriers to equal the striking power and fighter screen of a single Essex.

Furthermore, the American design was better suited to the realities of the Pacific War. The vast distances and need for sustained high-tempo operations demanded the long range and massive fuel capacity that were hallmarks of the Essex class. The British Pacific Fleet with its shorter-legged ships and less experienced fleet train could not have maintained the relentless operational pace of Task Force 58.

 Ultimately, there was no single better carrier. Each was an optimized solution for a different set of problems. The Royal Navy, shaped by war in the confined seas of Europe, built a ship to survive. The US Navy envisioning a war of annihilation across an ocean built a ship to deliver a knockout blow. The kamicazi was the unforeseen variable and by sheer chance the British design proved to be the almost perfect passive countermeasure.

As the American naval historian Samuel Elliot Morrison later wrote, “A kamicazi hitting a steel deck crumpled up like a scrambled egg and did relatively little damage, whilst one crashing the wooden flight deck of an American carrier usually penetrated to the hangar deck and raised hell below. The lessons learned in the fire off Okinawa were not forgotten.

 When the United States Navy laid down its next generation of carriers, the Midway class, the design incorporated a key feature proven by their British allies, a heavy, fully armored flight deck. The duel of philosophies had ended, and a new synthesis born from the brutal experience of war would shape the future of naval aviation.