JAPANESE SUB I-58 SINKS HEAVY CRUISER USS INDIANAPOLIS

Philippine Sea Between Guam Island and Leyte Gulf • July 30, 1945

On July 15, 1945, Capt. Charles B. McVay III, 46‑year-old skipper of the USS Indi­an­apo­lis, a fast Port­land-class crui­ser in Cali­for­nia for repairs, received orders to pick up some special cargo at Hun­ters Point (prede­ces­sor name for the now-closed San Fran­cisco Naval Yard). Eleven days later, on July 26, Indi­an­apo­lis unloaded her mysteri­ous cargo—a large crate that had been secured to its deck and a 2‑ft.-long metal cylin­der placed in the flag lieu­ten­ant’s cabin—all delivered under tight secu­rity to the B‑29 Super­fortress heavy bomber base on the Central Pacific island of Tinian in the Marianas. Of course, the key item on Indi­an­apo­lis’ top-secret cargo mani­fest was none other than the precious fis­sile com­po­nents for “Little Boy,” the code­name for the atomic bomb that would obliterate Hiroshima, Japan, on August 6, 1945.

Four days after leaving Tinian, just after mid­night on this date, July 30, 1945, 6 Type 95 wake­less tor­pe­does, the fastest and most deadly in use by any under­water navy in World War II, were launched, 3 seconds apart, by Japa­nese sub­marine I‑58, 36‑year-old Lt. Cdr. Mochit­sura Hashi­moto com­manding. Two 1,200‑pound/­544-kilo­gram war­heads struck the Indi­an­apo­lis 50 seconds later, one in the star­board bow and one amids­hips, as the heavy cruiser was en route to Leyte Gulf in the Philip­pines for gun­nery drills in anti­ci­pa­tion of the Allied inva­sion of Japan. In so doing I‑58 inflicted the greatest loss of life in U.S. naval his­tory: 300 officers, sai­lors, and Marines were killed in the 27‑minute attack, and the remaining 896 of the ship’s com­ple­ment bobbed in the unfor­giving sun and shark-infested waters of the South Paci­fic for 4 days and nights with­out the U.S. Navy having a clue the ship was missing. When at last the bobbing men were acci­dent­ally spotted by a Navy patrol bomber on a rou­tine mis­sion and rescued the next day, August 3, just 316 out of the origi­nal 1,196 sailors and Marines had sur­vived the sinking, expo­sure to oil, sun, and sea, dehy­dra­tion, salt­water poi­soning, and prowling sharks—reputedly the most shark attacks on humans in history. News of the tragedy was with­held from the Amer­i­can public for 16 days and went largely unnoticed owing to the momen­tous events of August 6 and 9 on the Japanese homeland.

The tragic demise of Indi­an­apo­lis and the fate of her crew was not assuaged by scape­goating Capt. Charles McVay in a Naval court-martial con­vened in late 1945. It was the judg­ment of the court that McVay was cul­pa­ble for the loss of his ship and crew. Although Indi­an­apo­lis had a top speed of 32.5 knots/­52 km/h, the fast cruiser had neither escort ves­sel (requested but rejected as unnec­es­sary) nor under­water detec­tion equip­ment, which con­ceiv­ably could have altered events. Worse, McVay was denied vital infor­ma­tion about a group of Japa­nese sub­marines oper­a­ting in close prox­im­ity of the Indi­an­apo­lis’ route. The ill-fated cruiser was on her own in pre­sum­ably safe waters. The panel of judges came down on McVay for “hazarding his ship” by failing to steam in a zig­zag pat­tern. According to Lt. Cdr. Hashi­moto’s own (entirely believ­able) testi­mony at McVay’s court-martial, zig­zagging wouldn’t have mattered one bit. Fleet Admiral Chester Nimitz even­tually remitted McVay’s sen­tence, although his con­vic­tion stayed on the books. McVay was restored to active duty and remained in the Navy until he retired in June 1949 as a rear admiral. But the deaths of his men in the ocean con­tin­ued to haunt him until, on Novem­ber 6, 1968, he killed him­self. The Indi­an­apo­lis had tragi­cally claimed its last victim. Thirty-two years passed before an act of the U.S. Congress exonerated the ex-skipper.

USS Indianapolis and Japanese Sub I-58, July 1945

Left: USS Indi­a­nap­o­lis off California’s Mare Island, July 10, 1945, days after the heavy cruiser’s final over­haul and repair of com­bat damage (incurred on March 31, 1945, off Oki­nawa) and 5 days before setting off for the Cen­tral Paci­fic island of Tinian to deliver crit­ical ele­ments of the atomic bomb that was dropped on Hiro­shima, Japan. The 9,800‑ton, 610‑foot/­186‑meter-long heavy cruiser served in numer­ous head­line-grabbing naval engage­ments, among them the Battle of the Coral Sea, the Battle of Mid­way, the Guadal­canal Cam­paign, the Battle of Leyte Gulf, the Battle of the Philip­pine Sea, the Battle of Iwo Jima, and the Battle of Oki­nawa. Indi­an­apo­lis served as a fleet flag­ship for Vice Admiral Ray­mond Spruance when he com­manded the U.S. Fifth Fleet in its battles across the Central Pacific. Sunk a half month before Japan’s uncon­di­tional surrender, Indianapolis was the last victim of the Japanese Navy.

Right: U.S. Navy preparing I‑58 for scuttling, April 1, 1946. I‑58 was a Type B3 sub­marine built and launched in June 1943 and displaced 2,200 tons. Jet-black and sleek, it was one-and-a-half times larger than the new Balao‑class Amer­i­can subs. Three hun­dred and fifty feet/­107 meters long and with 2 Kam­pon diesel engines pro­ducing 4,700 hp, I‑58 could cruise 21,000 miles/­33,796 kilo­meters at 17 knots/­31 km/h on the sur­face and 12 knots/­22 km/h sub­merged, a very respect­able dis­tance and speed for an under­water boat. One of the best and most skilled sub­marine offi­cers in the Impe­rial Japa­nese Navy, 36‑year-old Lt. Cdr. Mochitsura Hashi­moto com­manded I‑58’s crew of 107 offi­cers and enlisted men, many of whom he chose from other subs he had served on since becoming torpedo offi­cer on I‑24 in October 1941.

Left: This view of I‑58’s torpedo room shows 3 crew­men standing in front of the breach end of 4 21 in./­533 mm tor­pedo tubes. (The 2 lowest tubes can’t be seen.) The photo was taken at Sasebo naval base in occu­pied Japan in 1946. I‑class ves­sels had 6 tubes in the bow and none at the stern in con­trast to Amer­i­can, British, and German subs, which had both bow and stern tor­pedo tubes. The I‑class boats carried 19 Type 95 wake­less tor­pe­does, the fastest and deadliest in use by any navy in World War II. The Type 95 was second only to the famous Type 93 Long Lance used by Japan­ese sur­face ships. A real ship killer at more than 23 feet/­7 meters-long and 3,600 lb./­15.9 kg, the Type 95 could travel up to 12,000 yards/­10,973 meters at nearly 56 knots/­104 km/h. The war­head weighed 1,200 lb./­544 kg, giving it con­sider­ably more punch than Amer­i­can Mark 14 and Mark 16 tor­pe­does. Adding to I‑58’s deadly tor­pe­do arse­nal were 4 Type 1 Kaiten human tor­pe­does. These were modi­fied Long Lance tor­pe­does fitted with a 1‑way pilot’s com­part­ment and were suspended from the sub’s deck during transit. Kaitens had few suc­cesses when loosed on U.S. ships. Kai­ten pilots sunk just 3 U.S. ships during the Pacific War for a loss of 106 of their craft. Hashi­moto, being the skilled tor­pedo offi­cer that he was, stuck by his training and expe­ri­ence and sent the USS Indi­an­apo­lis and the bulk of her crew to their deaths using his trusty Type 95 torpedoes.

Right: This photo is believed to depict crew­men in action aboard the I‑58 in 1945 shortly before the fateful encounter with Indi­an­apo­lis. Up until then I‑58 had failed to sink a single enemy ship. Against his better judg­ment Hashi­moto sent 2 Kai­tens to strike a U.S. tanker and escorting destroyer 3 days before sinking the India­na­polis. Neither Kai­ten was success­ful, and the explo­sions Hashi­moto heard on his acous­tical head­phone were likely the torpedo pilots self-destructing.

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