The War Below Read online

  The assault on Truk represented another milestone in America’s advance across the Pacific. The summer of 1943 saw the United States shift from defense to offense. American forces by that time had driven the Japanese from the Aleutians, captured as part of the attack on Midway. A network of air and naval bases protected supply lines across the south and southwest Pacific, while battles in the Solomons and New Guinea had cost Japan important forward bases and chewed up the country’s air and naval forces. America planned to capitalize on its growing strength to capture or neutralize strategic islands across the central Pacific, including the Gilberts and Marshalls, the Carolines, and the Marianas. This maritime march west through Micronesia, coupled with MacArthur’s drive north through New Guinea and the Philippines, promised to place the enemy’s homeland within reach of America’s bombers. War planners calculated that only with Japan’s industrial cities reduced to rubble would the emperor surrender.

  This road through the central Pacific promised much bloodshed as Japanese leaders depended on Micronesia for defense, providing vital airfields and fleet anchorages to repel invaders. Japan had captured the Marshalls, Carolines, and much of the Marianas from Germany in the Great War. Barring foreign ships and visitors, Japan had spent the interwar years militarizing many of the islands, building barracks, airstrips, and seaplane bases, all under the pretense of cultural improvements. To prevent the possible fall of the islands, Japan designed each group with its own defensive system. The largest atoll in the world with a 839-square-mile lagoon, Kwajalein served as the defensive heart of the Marshalls while Truk played the same role for the Carolines and Saipan for the Marianas.

  The United States had set its sights first on the Gilbert Islands, a former British colony more than 2,000 miles west of Hawaii that Japan had grabbed in the days after the attack on Pearl Harbor. Seizure of this string of sixteen tiny equatorial atolls—the largest just fifteen square miles—would give America a foothold to invade the Marshalls, the next island group to the north. Forces from there could advance through the Carolines and on to the Marianas, the ultimate prize, which would provide American bombers the coveted runway to reach Japan. Troops hit the beaches of Tarawa in the Gilberts in late November 1943, fighting hand-to-hand against entrenched Japanese forces that left more than a thousand Americans dead and twice as many injured at the end of the seventy-six-hour battle. Crews readied four airfields in the Gilberts by December with three able to accommodate heavy bombers. American land-based and carrier planes bombed the Japanese in the Marshall Islands, Wake, and Nauru to hold these advances.

  The United States next turned to the Marshalls, consisting of twenty-nine coral atolls and five separate islands. The total dry land in the Marshalls added up to just seventy square miles peppered across an area of ocean almost three times the size of Texas. Strategists anticipated better fortifications than in the Gilberts, since the Japanese had controlled the Marshalls before the war. America overlooked no detail in preparation for the January 31, 1944, invasion of Kwajalein and Majuro atolls, from assembling an armada of 217 ships to ferry more than 60,000 troops to including fifty harmonicas and seven ukuleles. The Navy’s twelve carriers boasted some 700 planes compared to Japan’s 110; American forces wiped out ninety-two of those planes in a single pre-invasion strike. Battleships and heavy cruisers pounded the islands before American troops charged ashore, easily overwhelming the Japanese, as evidenced by the lopsided casualties: the United States suffered 334 killed compared to the more than 8,400 dead Japan counted.

  The success of the Marshalls invasion had led the Navy to push up plans to seize Eniwetok, originally scheduled for May. The strategic atoll along the northwestern edge of the Marshalls would play a vital role in the drive through the neighboring Caroline Islands. To protect American forces at Eniwetok, the Navy planned a carrier raid against Truk, dubbed Operation Hailstone. Tang’s patrol around this enemy stronghold in the Carolines supported that operation. Home to as many as 11,500 Japanese soldiers, sailors, and airmen, Truk played a similar strategic role for Japan as Hawaii did for America. The press dubbed this fortress built atop the peaks of undersea mountains “Japan’s Pearl Harbor” and the “Gibraltar of the Pacific.” Nine aircraft carriers and seven battleships, cruisers, and destroyers steamed toward this central Pacific citadel for the February 17–18 attack. War planners hoped Tang and other submarines could pick off enemy ships in advance of the strikes and then torpedo escaping vessels afterward.

  O’Kane was eager to oblige.

  Tang’s support of Operation Hailstone represented a larger shift in the undersea service’s mission. Submarines had largely operated throughout the war’s first two years—with the exception of Midway and some operations in the Solomons—as lone raiders tasked to target Japan’s naval and merchant fleets. The invasion of the Gilberts and the launch of America’s offensive drive across the Pacific demanded a new role. Submarines would continue to destroy Japan’s merchant fleet, but increasingly the Navy called on the undersea service to support major fleet operations. Those tasks assigned to the service played to a submarine’s inherent strengths. The boats could slip into Japanese-controlled waters to take important weather readings in advance of air strikes and snap periscope photos of beaches where troops might land. Submarines during an invasion could cripple the enemy’s supply lines and intercept warships that might counter an operation as well as pluck downed American pilots from the waves.

  Ten submarines deployed for the Gilberts invasion. Since weather in the Pacific moves west to east, America had no way of determining conditions in advance of the assault. Armed with weather balloons and a newly recruited aerologist, former Drum skipper Robert Rice parked Paddle 300 miles west of Tarawa. At sunset for the five days leading up to the invasion, Paddle fired off a report of atmospheric wind direction and velocities. The submarine Nautilus reported surf conditions at Tarawa the day before the invasion and landed seventy-eight Marines on Apamama atoll, even bombarding entrenched Japanese forces with its two six-inch deck guns. Nautilus and Plunger both served as lifeguards for downed aviators while other boats lurked near Truk’s entrances and along the major sea routes through the Marshalls to monitor enemy fleet movements that might counter America’s invasion. The success of the operation led the Navy to call in submarines for the Marshalls invasion and now for Operation Hailstone.

  • • •

  Frazee wrapped up his calculations at the control room table. Tang’s second in command, nicknamed “Fraz,” sported dark hair, a medium build, and gentle features that masked a ruggedness developed during an adolescence marred by economic hardship. The Naval Academy offered Frazee four years of stability and a chance to play soccer and lacrosse, though he preferred fifty-cent nine-ball at a local pool hall. Like O’Kane, Frazee had been a mediocre student, graduating in the bottom half of the 1939 class. But the twenty-eight-year-old lieutenant’s youth disguised his extensive wartime record. Frazee had already served seven patrols on the submarine Grayback, earning a Silver Star for one, before landing as O’Kane’s exec on Tang.

  Frazee shouted his suggested course and speed for the night up to O’Kane in the conning tower. The barometer dropped shortly before midnight and the waves rose. O’Kane polished off a cup of coffee and climbed to the bridge. The skipper and his executive officer studied the whitecaps. The waves stretched to the horizon, disappearing into the black night. The pounding seas cut Tang’s eighteen-knot speed by almost two knots and O’Kane knew the situation would only worsen before dawn. If the heavy seas forced Tang to miss the plotted intercept point, O’Kane told Frazee he could adjust the course left at dawn and still cut off the convoy later in the morning. That would require Tang to run on the surface after daybreak. Such a brazen and exposed chase so close to Japanese operations around Truk exposed Tang to the possibility of an air attack. Frazee listened to his skipper’s plan. “We can dive faster than a Zeke, Captain,” Frazee responded, referring to a Zero fighter.

  The seas calmed by
morning. The dawn star fix showed that Tang remained some forty miles short of the convoy’s track. O’Kane ordered the submarine to come left twenty degrees. All four engines roared. Sailors used the aircraft radar sparingly, fearful the Japanese might detect the signal. With each radar check, men noted distant pips, which O’Kane surmised could be island plane traffic or even convoy air escorts. One pip that had remained some eighteen miles out began to close the distance shortly before 9:30 a.m. The radar operator relayed reports as it closed to within twelve miles. O’Kane couldn’t risk being spotted. He flashed his exec the thumbs-down sign and the submarine slipped beneath the waves to eighty feet. Tang surfaced soon after. This time lookouts failed to spot a Japanese fighter until it appeared right off the port bow, forcing the submarine back down, this time to 300 feet. “All was clear,” O’Kane wrote. “But now that we had been sighted, there would be no ships along that course—and most probably along any other course for Truk—on this day.”

  O’Kane had blown it, not just for Tang, but for Skate and Sunfish, too. Japanese war planners would cancel convoys and reroute others. Escorts and air patrols would increase. The element of surprise had vanished. O’Kane could only hope the convoy had returned to Gray Feather Bank, a move that might allow him to salvage an attack once the Japanese felt the area safe again. Tang spent the afternoon submerged as officers swept the horizon with seventeen feet of periscope in the unlikely chance a convoy might risk it, but nothing appeared. Any ship that departed Gray Feather Bank for Truk might vary its course to the north or the south, but it still had to steam in one direction: east. Toward Tang. If O’Kane ran north–south legs throughout the night he might intercept a convoy. He ordered Tang to patrol on the surface at fifteen knots with its radar to cover as much distance as possible.

  No ship appeared that night.

  Nor the next day.

  The frustrated skipper’s luck changed on February 17 at 12:25 a.m. Radar picked up a convoy to the northwest at a range of almost eighteen miles. O’Kane ordered Tang to close while the tracking party determined the convoy’s course and zigzag pattern. Once armed with that critical information, O’Kane planned to maneuver seven miles ahead to intercept. Sailors soon determined that the convoy steamed east directly into the rising half-moon at 8.5 knots. The convoy had originally departed Yokohama almost two weeks earlier with as many as thirty ships. Most had since split off, bound for other ports. The five remaining vessels, loaded down with munitions and troops, steamed toward Truk, accompanied by four escorts that Tang’s radar showed encircled the convoy. “It looked more like a small task force than a convoy,” O’Kane noted. “The high ratio of escorts to merchantmen showed what had been happening: Japan’s merchant fleet was being sunk at three times the rate of its escorts.”

  An Ultra message arrived from Pearl Harbor, this time addressed to Tang and copied to Skate and Sunfish. “Convoy will depart Gray Feather Bank at twenty two hundred February sixteen for Truk,” the message read. “Note Skate and Sunfish this is the convoy you were to have attacked but one of you was sighted and convoy ordered to return onto Gray Feather Bank.” That convoy—now some two hours into its voyage—loomed in Tang’s sights. O’Kane chafed at the writer safely back in Hawaii who—though blaming his fellow sub skippers—had indirectly called him out for being spotted. While he downplayed his foul-up as an occupational risk, his superiors took a dim view: a convoy that should be on the bottom wasn’t. O’Kane refocused. Why would a convoy risk such a perilous trip at night? The moon glowed overhead, silhouetting ships and making them easy prey. Lookouts also faced greater challenges spotting submarines in the dark. It didn’t make sense. Tang approached an attack position at 2:19 a.m. ahead of the convoy that steamed more than eight miles away.

  A dark silhouette suddenly appeared 7,000 yards astern—the convoy’s starboard flanking escort. The patrol charged after Tang. Even with the moonlight O’Kane couldn’t believe the escort’s lookouts had seen the submarine’s low and sleek shape. It must be armed with radar. No wonder it had dared such a risky nighttime transit. Tang continued at flank speed, but the escort still closed the distance. The skipper had no choice but to dive. The klaxon sounded and the men on the bridge poured through the hatch. Tang slipped seconds later beneath the surface of the dark water. The skipper watched through the periscope as the escort kept coming, its frothy bow wave looming large. O’Kane had to go deep. Tang reached 450 feet before the first depth charge exploded. Another blast shook the submarine followed by three more. None caused any damage. “His attack was half-hearted,” O’Kane later wrote in his report. “We were able to return to radar depth fifteen minutes after he passed by.”

  O’Kane refused to be shaken off in his first real test since Wahoo. Everyone from the teenage seamen on board Tang to the senior officers at Pearl Harbor would judge him. O’Kane ordered full speed submerged, now hidden beneath a temperature gradient that shielded the submarine from the escort’s sonar. Tang soon climbed back up to radar and then to periscope depth. The convoy, still five miles out, headed O’Kane’s way. He waited. The skipper planned to fire his bow tubes, but when the lead freighter reached 3,000 yards, he saw that the ship had turned and would now pass Tang’s stern. O’Kane adjusted, ordering the outer doors aft opened. Unlike the manual cranks used on older boats, Tang’s operated by a hydraulic system. He watched the leading escort cross to the freighter’s opposite bow away from Tang. The port escort passed just 100 yards from Tang’s bow, oblivious to the lurking submarine. O’Kane had penetrated the escort screen. “We were on the inside,” he wrote. “Nothing could stop us!”

  The 6,854-ton Gyoten Maru—a former British ship once known as the Empire Moonbeam—closed to just 1,500 yards on track to cross Tang’s stern in seconds. O’Kane watched it chug across his scope. “Constant bearing,” he said. “Mark!”

  “Set.”

  “Fire!”

  Frazee pressed the firing plunger at 3:35 a.m. Tang shook as a blast of compressed air ejected a one-and-a-half-ton torpedo from tube seven, its steam-driven propellers kicking on with a whine as it cleared the submarine. O’Kane fired three more times. Petty Officer 1st Class Floyd Caverly, the twenty-six-year-old Minnesotan soundman, listened through his black headphones as the torpedoes zoomed toward the target at forty-six knots. “All hot, straight, and normal,” he reported.

  “What’s the time of the run?” O’Kane asked.

  “Fifty-eight seconds, Captain,” Frazee replied.

  Chief Petty Officer Sidney Jones, Tang’s senior quartermaster, called out the time to detonation. Ten seconds passed. Twenty. Then thirty. O’Kane was anxious. He had fired his first shots of the war as skipper. He wanted to be successful. Forty-five seconds after firing, the skipper raised the periscope. He sighted Gyoten Maru’s silhouette. Nine seconds later, the ship exploded. O’Kane watched the stern vanish. The next thirteen seconds delivered two more hits. The explosions knocked out Gyoten Maru’s radio. The wounded ship’s siren rang out as water flooded its bowels. The stunned escorts milled around Gyoten Maru before the freighter broke in half and slipped beneath the waves. O’Kane had sunk his first ship. The skipper ordered Tang to hide beneath the 375-foot temperature gradient. The submarine leveled off at 575 feet and cleared the area as distant depth charges exploded.

  • • •

  The next few days remained slow for Tang as it patrolled sixteen miles off the island of Ulul. Ten submarines now lurked in the waters around Truk. Darter, Searaven, and Seal performed lifeguard duty while Skate, Sunfish, Aspro, Burrfish, Dace, and Gato joined Tang to intercept ships. But Operation Hailstone belonged to the aviators, who flew 1,250 sorties, blackening the skies over the sunken mountain range. Five hundred tons of bombs and torpedoes pounded Japanese airfields, ships, and fuel and ammunition depots. The two-day attack cost Japan 270 planes along with twenty-six merchant ships and six combatants for a total tonnage lost of some 200,000. The laconic Pacific Fleet Commander Admiral Chester Nimitz bragged to the press ab
out Hailstone’s success. “The Pacific Fleet has returned at Truk the visit made by the Japanese fleet at Pearl Harbor on Dec. 7, 1941, and effected a partial settlement of the debt.”

  O’Kane’s new orders arrived after dawn on February 20. The fast carrier task force that had reduced Truk to ruins planned to hammer Japanese forces at Saipan. Tang and four other submarines from Truk would head some 700 miles north and await additional orders. O’Kane suspected he was the first to learn of the new plan. Submarines could receive fox messages—the nightly broadcasts from Pearl Harbor to boats at sea—only when on the surface to recharge batteries. Tang had come up soon after its dawn dive, just in time to pick up the chance message. If he was correct, Tang would have a 250-mile head start on the other subs. Furthermore, with all the submarines now around Truk, O’Kane doubted that any patrolled the Marianas, fertile hunting ground. The skipper ordered Tang, then running on just one engine, to make eighteen knots. “There had to be ships,” he wrote. “Tang would have the Marianas all to herself, at least for a time.”