World War II Day by Day

Yokosuka Naval Arsenal, Japan • October 8, 1944

Shinano was the largest aircraft carrier ever built until the early 1960s. Her keel was laid down on May 2, 1940, at the Yoko­suka Naval Arse­nal south of Tokyo. She was launched 4½ years later on this date, Octo­ber 8, 1944. The carrier was to have been the third of the legen­dary Yamato-class super battle­ships, whose keels were laid down in the late 1930s. In the wake of the Battle of Mid­way (June 4–7, 1942) and calam­i­tous loss of four Japa­nese fleet carriers (Akagi, Kaga, Soryu, and Hiryu carrying 248 com­bat air­craft), the Imperial Japa­nese Navy ordered the hull, 45 per­cent com­plete, con­verted to an air­craft carrier. The con­ver­sion caused the battle­ship’s main deck to become Shinano’s hangar deck for half the num­ber of air­craft aboard a typical Japa­nese fleet carrier. A flight deck was built on top of that deck to launch and recover planes. Shi­nano’s role was that of a heavily armored support air­craft carrier. Its hangar held its own air group of 18 fighters, 18 torpedo-dive bombers, and 6 recon­nais­sance air­craft with room for upward of 120 replacement aircraft.

At 69,000 tons Shinano’s displacement was several thou­sand tons less than her two half-sister battle­wagons, Yamato and Musashi. In part that was due to Shi­nano’s main armor belt being two-thirds less thick as well as the absence of the 9 devas­ta­ting 18‑inch cannon of her half-sisters. Other than its own air­craft, Shi­nano’s arma­ment con­sisted of 16 five-inch anti­air­craft guns, 105 25mm anti­air­craft machine guns, and 12 mul­tiple rocket launchers with 4.7‑inch unguided anti­air­craft rockets. With an esti­mated range of 10,000 nau­ti­cal miles, Shi­nano was to be crewed by 2,400 officers and enlisted men.

Shinano was commissioned on November 19, 1944, but an acci­dent the pre­vious month pre­vented her from begin­ning serious sea trials until Novem­ber 28. On Octo­ber 8, launch day, a dry dock gate buckled, allowing a surge of sea­water to smash the bow of the 872‑foot-long ship against the dock’s head­wall three times. Repairs took 2½ weeks, followed by a partial fitting-out and more sea trials.

Meanwhile, on November 24, 1944, the United States Army Air Forces launched its first strike of Boeing B‑29 Super­for­tresses from the Mari­anna Islands toward Tokyo. The target was an air­craft engine plant in the arse­nal sec­tor of the cap­i­tal north of the ship­yard where Shi­nano was build and berthed. A U.S. recon­nais­sance fly-over added to the pres­sure that the INJ order Shi­nano to a safer loca­tion. Late on Novem­ber 28, 1941, Shi­nano steamed south for Kure Naval Arse­nal, Hiro­shima, Japan’s single-largest naval base, not­with­standing that her water­tight doors had yet to be installed, holes in the com­part­ment bulk­heads for cables, venti­la­tion ducts, and pipes were still unsealed, and fire mains and bailing sys­tems lacked pumps. Aboard was a com­ple­ment of 2,175 crew­men, plus 300 ship­yard workers and 40 civil­ians engaged in making Shinano, in due course, shipshape.

Shinano steamed right into the arms of the USS Archer­fish. Two hours and 48 minutes after departing Yoko­suka’s ship­yard with a trio of es­corting destroyers, the quartet lit up Archer­fish’s radar screen. Like­wise Shi­nano, as she zig­zagged her way south to Kure, had picked up the uniden­ti­fied sub. Cap­tain Toshio Abe main­tained a tight leash on his screening destroyers, believing the intruder to be a wolf­pack decoy intent on luring away his escorts. At 3:15 a.m., Novem­ber 29, Abe changed course 30 degrees and veered broad­side right into the path of Archer­fish’s 6 loosed Mark 14 tor­pe­does, 4 of which found their mark.

Just shy of 11 a.m. Shi­nano capsized and sank, taking Abe and 1,434 naval men and civil­ians to their deaths 65 miles off the east coast of Honshū Island. Sur­vi­vors num­bered 1,112. Shi­nano’s demise was a well-kept secret. U.S. Pacific Fleet ini­tially cred­ited Archer­fish, skip­pered by Com­mander Joseph F. Enright, with sinking a cruiser (!), then settled on a 28,000–ton Hiyō–class air­craft carrier. After the war the record was corrected.

World War II Version of David Meets Goliath: USS Archerfish Versus Shinano, Imperial Japan’s Largest Warship

Above: Artist’s color rendering of the USS Archer­fish’s tor­pedo strike on the Shi­nano on her maiden voyage, Novem­ber 29, 1944. In 8‑second inter­vals 4 war­heads from a vessel 46 times smaller than its prey deto­nated against Shi­nano’s supposedly impreg­nable hull. At first Shi­nano’s offi­cers weren’t unduly worried about the carrier’s surviv­a­bil­ity and believed its destroyer escorts could tow the listing ship, thou­sands of tons of sea­water hea­vier, to a safe sanc­tu­ary. A single attempt was aborted when tow cables snapped. At 10:18 a.m., 7 hours after the attack, the abandon-ship order was sounded. Chaos reigned. Crew­members, con­scripted Korean laborers, and civil­ian pas­sen­gers had not been drilled on escape pro­ce­dures. Nearly 40 minutes later the mor­tally wounded carrier heeled and sank stern-first. Former destroyer com­mander and sur­vi­vor of the crushing Japa­nese defeat at Mid­way, Cap­tain Toshio Abe, was among Archer­fish’s victims. To sup­press news of the carrier’s embar­ras­sing loss, the 1,081 sur­vi­ving offi­cers, petty offi­cers, enlisted men and the 32 civil­ians were iso­lated on the island of Mitsuko-Jima near Kure Naval Arsenal, Shinano’s destination, until January 1945.

Left: This is just one of two photographs ever taken of the bulbous, clipper bow Shinano, which was built secretly at Yoko­suka Naval Arsenal by seques­tered workers under the watch­ful eyes of the Impe­rial Kem­pei secret police. A civil­ian photo­grapher aboard a harbor tug snapped the photo on Novem­ber 11, 1944, during the Shi­nano’s ini­tial sea trials in Tokyo Bay, just north of the ship­yard where she was built. A Boeing B‑29 recon­nais­sance air­craft took the only other photo­graph 10 days earlier. As seen in this photo­graph, much of Shi­nano’s single hangar was open for ven­ti­la­tion pur­poses at both ends as well as for jet­ti­soning burning aircraft or ordi­nance. Its armored flight deck of 3 inches armor plating and 3/4‑inch ordi­nary steel was designed to with­stand a direct hit by a 1,100‑pound bomb. The joints between the main armored belt and the armored bulk­heads below the water­line were sus­cep­ti­ble to leak­age, and Archer­fish’s tor­pe­does hit that joint. Captain Toshio Abe and his offi­cers scorned Amer­i­can tor­pe­does anyway, which had a poor repu­ta­tion even among some U.S. sailors. It took a full hour before Abe realized the gra­vity of his situ­a­tion, but of course Shi­nano’s fate had already been sealed when she crossed paths with the American sub.

Right: USS Archerfish’s fifth war cruise was skippered by Com­mander Joseph Enright. Archer­fish (also Archer-Fish) was a Balao-class submarine named for a fish that kills its victims with a lethal blast of water from below. Enright had pre­viously skip­pered a sub and botched a chance at sinking the air­craft carrier Sho­kaku. He and the Archer­fish’s exe­cu­tive offi­cer, Lt. Cmdr. Bob Bob­czyn­ski, put their heads together to plot the antic­i­pated anti­sub­marine zig­zag course of the faster uniden­ti­fied vessel (Shi­nano). Enright even sent a wire­less mes­sage informing Pearl Harbor of his posi­tion and his inten­tions in the event another Amer­i­can sub was better posi­tioned to inter­cept and sink his target. Just after a quarter past three on the morning of Novem­ber 29, 1944, four of Archer­fish’s six Mark 14 torpe­does tore into Shi­nano’s star­board hull con­taining oilers, engines, steering equip­ment, elec­tronic and com­mu­ni­ca­tion gear, and ammu­ni­tion maga­zines—Enright’s aim could not have been better. Once the exis­tence of Shi­nano was dis­covered, the U.S. Navy cred­ited Enright and the Archer­fish crew with sinking the largest war­ship ever sunk by a sub­marine and awarded the sub’s com­mander the Navy Cross, the depart­ment’s second-highest mili­tary deco­ra­tion for extraor­di­nary hero­ism in com­bat; Archerfish received a Presidential Unit Citation.

Japan’s 69,000-Ton Shinano Inaugurates Era of Super-Sized Fleet Carriers, Set in Context