Photo courtesy of Hap Halloran

The Imperial Japanese Navy, which had never been defeated prior to Midway, had inherited the attractive, but dangerous, concept of the "Decisive Battle" from Admiral Togo, who, in 1905, destroyed two Russian fleets in decisive battles in Tsushima Straits. This concept naturally appealed to the warrior spirit of Bushido which pervaded the Japanese military and it soon became doctrine in the Imperial Navy. More than once during the Pacific War with the United States the dogmatic persistence of this belief caused the Japanese to devise tactics which gambled all on a single, great victory over the American fleet. By mid-1944, the US Navy was sufficiently strong to enable it to indulge the same philosophy, and one objective of American operations became the luring of the Japanese Combined Fleet out for a "decisive" engagement near the Mariana Islands.

The Mariana Islands had been part of the Spanish Empire since their discovery in 1521, but were lost in 1898 following Spain's defeat in the Spanish-American War by the United States. The U.S. also acquired Guam in the Marianas, as well as the Philippines and Puerto Rico. In 1899, Germany purchased the Carolines, Marshalls, and the remaining Mariana Islands, of which Saipan was one, from Spain for $4,000,000. In 1914, Japan, using her 1910 treaty with England as an excuse, seized German possessions in China and the Pacific. When, in 1929 the League of Nations gave Japan a mandate over the Caroline and Mariana Islands, she suddenly had an empire that stretched across the Pacific, north of the equator, almost to Hawaii.

Saipan is a tropical island 14 miles long and 5 miles at its widest, located about 15 degrees north of the Equator and just east of 130 degrees of Longitude and is mainly volcanic in origin. Dominating its center is Mount Tapotchau, a 1554 foot peak which forms the apex of a spiny backbone, a jagged ridge with thousands of caves, which runs down the center of the island between Mt. Tapotchau and Mt. Marpi at the northern end. To the north and east of this ridge a succession of high plateaus and rolling hills end abruptly in steep coastal flats and sheer cliffs that drop hundreds of feet to the sea. To the south and west, the land rolls out onto a long coastal plain fringed with beaches. As with most coral and volcanic islands, a reef rings the island in varying distances from shore, and in this case, mostly on the western side of the island.

Located 1500 miles east of Manila and 1300 miles SE of Tokyo, the Marianas, in 1941, were part of a supposed ring of "fortress islands" which the Japanese had created in direct violation of the League of Nations mandate. Actually very little construction of a defensive nature took place in any of the islands, except for Truk (now Chuuk) and Palau in the Carolines, until after Pearl Harbor. On Saipan, the second largest island of the Marianas group, Aslito Airfield had been built in 1935 (near the site of the present airport on the southern tip of the island). A little later, a seaplane base was built on the west coast at Tanapag, and a fighter strip laid out at Marpi Point, on the northern end.

Following a rapid influx of Japanese settlers, Saipan became a bustling community, a Little Tokyo, and, during the 30's, sugar cane became an important export, managed by the South Sea Development Co., a Japanese monopoly. By December 1941, Saipan had a population of more than 30,000 people, including 25,000 Japanese, of which a high percentage were Okinawan construction workers and their families. The native Chamarro's numbered less than 4000.

In the first two years of the war Saipan was used mainly as a supply and staging area, even though the Japanese Imperial General Headquarters considered it a key stronghold whose loss would cut Japanese supply lines to the south and isolate Truk, 600 miles southeast of Guam. Furthermore, the JIGH realized that possession of the island by the Americans would provide forward bases from which B-29's could easily reach Japan. But even after the American conquest of Tarawa (23Nov.43) and Kwajelein (8 Feb.44), little was done to build up Saipan's defenses, other than a few pillboxes, and the garrison remained little more than a token force. In the early Spring of 1944, with the Marshall's and the Gilbert's securely in American hands, and Truk reduced and by-passed, Admiral Nimitz and his planners turned toward the Marianas, considering Guam as the primary target.

However, Saipan and Tinian were 100 miles closer to Japan, and since taking these two islands would deprive the Japan on Guam of air support, Admiral Nimitz decided to invade Saipan first and Guam three days later. On 23 February 1944, Saipan received the first taste of what lay in store when the Admiral's carrier-based planes attacked Aslito and Marpi airfields, catching them flat-footed. Of the seventy-four Japanese planes which managed to take off from Saipan, Tinian and Guam to meet the threat, only seven returned to base, and one hundred and one aircraft were destroyed on the ground, at a cost of only six U.S. planes. It was a prophetic score.

THE A-GO PLAN

On 1 March 1944, Admiral Koga Mineichi, Yamamoto's successor as CINC, Combined Fleet, had ordered a reorganization of the Japanese Navy, in which the 1st Mobile Fleet, under Vice Admiral Ozawa Jisaburo, would be the Main Body. Combined Fleet Headquarters would move to Saipan, and, with the "decisive battle" in mind, Koga ordered an increase in the numbers of land-based Naval air forces as well as an expansion to more bases within the Inner South Seas (the term used for the Marianas-Palau area). These aircraft were to support regular carrier aircraft in any naval operations within the area. Tinian, a small island barely a mile off the southern tip of Saipan, was to be the site of the headquarters. Vice Admiral Kakuta Kakuji, a veteran naval flier, was appointed to head this command.

The Navy's reorganization dove-tailed neatly with a plan Koga's staff had been working on for counter-attack against an American attempt to seize either the Carolines or the Marianas. The plan's code-name was Operation A or A-Go. Admiral Koga died in an plane crash before A-Go plans were completed, but details were hammered out by the end of April, and on 2 May, Admiral Toyoda Soemu, Koga's successor, issued notice that the "decisive battle area would be the Palaus, but if the Americans attacked in the Marianas, it would be necessary to 'lure' them south," into range of the Mobile Fleet and Admiral Kakuta's land-based aircraft.

The move would be accomplished in three stages: "a hop, skip and a jump" in order to get to an anchorage in the Philippines from which it could sortie. The "hop" would take the fleet to the island of Tawi Tawi, off the northeastern tip of Borneo, the "skip" was to take the fleet to the center of the Philippines, and the "jump" would be either to Palau or to the Marianas, depending upon which the Americans attacked. Accordingly, on 10 May, 1944, the 1st Mobile Fleet left Linga Roads and headed for Tawi Tawi.

Then, on 27 May, the Japanese Imperial General Headquarter's attention was diverted from the Central Pacific southward to Biak, an island, off the northwestern coast of New Guinea, where General Mac Arthur's forces had just landed. Now, once again Admiral Togo's legacy led the Japanese to devise a plan they hoped would lure the American fleet into a "decisive battle" near Palau -Operation KON, a plan to recapture Biak. Operation KON started on 3 June, but after the first two attempts failed, Combined Fleet Headquarters detached a portion of Admiral Ugaki's battleship fleet of five battleships, which included the Musashi and Yamato, ten cruisers and about 14 destroyers, from the 1st Mobile Fleet at Tawi Tawi and sent it to reinforce Operation KON. For the moment, the Central Pacific was quiet.

Then, around noon on 11 June, 208 fighter planes and 8 torpedo planes from the approaching invasion force, Task Force 58 struck Guam, Rota, Tinian and Saipan simultaneously. Approximately 500 Japanese planes were destroyed in the air and on the ground, seriously depleting the number of Kakuta's aircraft available to assist any fleet operations. This attack was followed on 12 June, by more air strikes and a heavy naval bombardment which convinced Combined Fleet Headquarters that Saipan was about to be invaded. Operation KON was canceled and Operation A-Go was activated.

Admiral Ozawa's 1st Mobile Fleet, which included his flagship, the newly commissioned carrier, Taiho, the fleet carriers Shokaku, Zuikaku, medium carriers Hiyo, Junyo, and the light carriers Zuiho, Ryjo, Chitose, and Chiyoda, was ordered to a rendezvous with Admiral Ugaki's battleship force east of the Philippines, where they would refuel and proceed to the relief of Saipan and the destruction of the American invasion fleet. Just before noon on 13 June, when the 1st Mobile fleet left its anchorage at Tawi Tawi and sortied into the Sulu Sea, it was observed by the U.S. submarine Redfin, skippered by Marshall H. Austin. The submarine was unable to reach an attack position, but followed the ships until dark, reporting their progress and position. That night the Japanese force refueled at the island of Guimaras, between Panay and Negros, and then proceeded into the Visayan Sea, and on through San Bernardino Strait, where it divided into three separate groups, each taking a different route to the rendezvous with Ugaki.

At dusk on 15 June, the same day the landings began on Saipan, another U.S. submarine, Flying Fish, commanded by Robert Risser, reported one of the groups near the San Bernardino Straits, between Samar and SE Luzon, heading east. A coast-watcher, who probably saw the same group of ships, radioed that there was a large Japanese fleet of eleven destroyers, ten cruisers, three battleships, and nine carriers with aerial escort, coming through the straits from the west. Receipt of this information caused Admiral Spruance, commander 5th Fleet to delay the invasion of Guam, scheduled for the 18th, until Rear Admiral Richmond Kelly Turner's transports and supply ships off Saipan were unloaded, after which they were to retire eastward to safety. TF 58, under Admiral Marc Mitscher, was sent to a position about 200 miles west of Saipan to await Ozawa's force. An hour or so after the Flying Fish's report, skipper Slade D. Cutter in submarine Seahorse, which was on station two hundred miles east of the Surigao Straits, reported a large group of battleships, Ugaki's southern force, steaming almost due north. On 16 June at 1700, Ozawa's three groups, unobserved now by any submarines, met with Ugaki's battleship force about 380 miles east by northeast of Mindinao. The ships refueled from their train of oilers and proceeded toward Saipan.

So far, none of the submarines that had observed the enemy groups had been able to position themselves for an attack on any of the ships, but on 17 June, this circumstance was about to change after Herman Kossler, commanding the submarine, Cavalla, made contact with a force of fifteen or more ships and trailed them for over 54 hours, periodically reporting their progress, position and direction.

Admiral Ozawa approached Saipan from the southwest with his force divided into two principal elements; one, Carrier Division 3, under Vice Admiral Kurita Takeo included three light carriers and a relatively heavy screen of surface ships. The second element, a hundred miles to the rear, was Ozawa's main body, Carrier Divisions 1 and 2, formed around the six other carriers and their screens. Ozawa's forces had only half the number of carrier planes - 430 against 891 - Mitscher did and this disadvantage was aggravated by the relative inexperience of most of the air crews.

During the afternoon of 18 June, Japanese scout planes spotted TF 58 about 200 miles west of Saipan. Kurita's force, in the van, moved ahead to a position about 300 miles from the American force, almost a hundred miles beyond the striking range of Mitscher's planes. Rear Admiral Obayashi Sueo, in command of the three carriers of Carrier Division 2, was closest to the Americans and had impulsively ordered an air strike, which Ozawa countermanded and the planes were recalled. Ozawa wanted to strike with a massive assault from all his carriers early the next morning, before any of his groups came within range of the American planes, whose range was only about 280 miles, while the range of the Japanese planes exceeded 300 miles.

The Americans were unaware of Ozawa's force until about midnight 18-19 June, when DF apparatus detected the ships. Though his mission was to "cover" Saipan and not to sortie, Admiral Mitscher asked for permission to engage the enemy at 0500, 19 June. Spruance feared that TF 58 would be lured away, allowing another Japanese task force to slip in and attack the invasion force. Mitscher's Fast Carrier Task Force included fifteen fleet carriers and light carriers, grouped into four task groups with screening cruisers and destroyers. Six fast modern battleships, normally part of the carrier task groups, had been detached to form the 5th Task Group, the Battle Line, which four days earlier had shelled Saipan's western shoreline prior to the landings. Now, the 5 groups, spaced 12 to 15 miles apart, were disposed to repel either a direct Japanese drive for Saipan from the west, or an end run around the American fleet. The Battle Line was held ready to meet a surface attack, should Ozawa launch one.

Dawn of 19 June was cloudy, with numerous scattered rain squalls dotting the area, when Ozawa launched sixteen search planes at 0445 hours. Two other groups of search planes were launched at intervals. Because of the limited visibility these aircraft searched until after 0730 before finding TF 58. Finally, at 0830, the first wave of forty-five bomb-carrying Zeros and eight torpedo planes covered by sixteen Zeros, took off from Taiho. Twenty-six minutes later, a second wave of one-hundred and twenty-eight planes took off. As this group was rising from the deck the submarine Albacore, commanded by James W. Blanchard, raised its periscope and saw the 31,000 ton carrier approaching rapidly on a line that would allow a near ideal torpedo spread. Despite a problem with the torpedo data computer, the six forward tubes were fired at the carrier in hopes that some would hit. On the way down, there were two faint explosions, but the skipper assumed that he had missed with all the torpedoes and made no radio report of the attack. Actually, one of the six torpedoes had hit the carrier.

As the last planes off Taiho rose and circled to form up, one of the pilots saw a line of bubbles streaking toward the ship and, realizing it was a torpedo, unhesitatingly crash-dived into it. Seconds later a second torpedo struck the starboard side of the ship. One such hit on a carrier seldom puts it out of action, let alone sinks it, but this hit was crucial. The most obvious damage to Taiho was the jammed forward aircraft elevator and gasoline filling the elevator pit from fuel tanks ruptured by the explosion, but Damage Control did not consider this to be serious and the huge ship plowed on as though it had been a rock thrown against its side instead of a torpedo. Hours later, Admiral Toyoda, aboard the Combined Fleet flagship, Oyodo, received a message that the ship had been "somewhat damaged".

According to the plan of Operation A-Go, the Japanese planes which had just taken off, after attacking TF 58, were to continue on to Guam to refuel and rearm. Then, joined by Admiral Kakuta's land-based planes from Guam, Tinian and Saipan, they were to make a second attack on the way back to their carriers. As yet, neither Ozawa nor Kurita was aware that the heavy carrier air strikes by TF 58 had already chopped the number of land-based aircraft down to a fraction of the expected number.

At 1000 hours TF 58's radar picked up Ozawa's first wave while they were still one hundred and fifty miles out. Hellcats that were hitting Guam were recalled to the fleet and TF 58 turned into the wind and began to launch aircraft in a rotation that would keep a maximum number of fighters aloft to meet the threat. Thirty minutes later, eleven Hellcats of the regular CAP, dived upon the approaching enemy. In the first clash, twenty-five Japanese planes went down, then sixteen more. Only one got through to make a hit on the battleship South Dakota, but no enemy planes got through to the carriers. Ozawa's second wave was still sixty miles away from the American fleet when Hellcats from the Essex found them, and in minutes seventy Japanese planes had been shot down. An oil slick, full of debris from the downed aircraft, stretched over a twelve mile long strip. This time though six dive bombers and a few torpedo planes got through to the carriers. The Bunker Hill was damaged slightly.

Meanwhile, the third wave from the Japanese carriers had been given the wrong coordinates and only twelve were diverted to the battle area. Of these, seven were shot down. The fourth wave was also misdirected and, after failing to find the American carriers, dropped their bombs into the sea and headed for Guam. As they made their final approach for landing at Orote Field, Hellcats swept in upon them and destroyed thirty planes. Seventeen others were so badly shot up that they crash-landed.

Ozawa's troubles were about to draw compound interest, when before noon on 19 June, the submarine, Cavalla, raised its periscope and found the 30,000 ton carrier, Shokaku, busy recovering aircraft. Cavalla closed to within 1100 yards and fired the six forward tubes and immediately plunged deep. As the boat descended, three distinct detonations were heard, and then the screws of the escorts as they swarmed over the patch of ocean where the submarine had been. For three hours the Cavalla played tag with over one hundred depth charges, and, when the submarine was finally able to come near enough the surface to raise its periscope, it was night and the sea was empty. The three hits had set off fires which caused a series of internal explosions which ripped through the ship, enveloping it in flames, and, a little after 1500 that afternoon, the Shokaku, veteran of Pearl Harbor and the Coral Sea, had rolled over and sunk.

In the several hours since the Albacore's torpedo had hit, the "somewhat damaged" Taiho had become a huge time bomb. In an effort to clear the damaged elevator shaft of gasoline fumes, ventilating fans had been turned on and the volatile, explosive vapors were circulated throughout the ship. About 1530 hours, the ship shuddered and slowed in the water as a gigantic explosion buckled the flight deck and blew out the hull sides of the hanger deck like a cherry bomb in a tin can. The ship began to take on water. Admiral Ozawa was urged to transfer his flag to the nearby heavy cruiser, Haguro, which he did reluctantly. At approximately 1815 hours, a second explosion literally ripped the Taiho asunder and ten minutes later she tilted heavily to port and slid, stern first, under the water, carrying with her 1650 officers and men. Thus, two Japanese fleet carriers had been sunk within a few hours of each other.

Aboard the Oyodo there was little doubt of the outcome of A-Go and Admiral Toyoda ordered a withdrawal. Meanwhile, having received reports that TF 58 had been badly damaged, Ozawa directed a night retirement to the northwest to refuel with the intention of resuming the attack next morning. The admiral believed that many of his missing planes had landed on Guam as planned and would return by dusk or in the morning. However, late in the afternoon of the 20th, an intercepted signal from an American scout plane told Ozawa that his force had been spotted and that he could expect an attack. The Japanese force increased speed to draw out of reach for a pre-dusk attack, but it was too late.

Admiral Mitscher had been steadily closing the distance between the two fleets with three of his four carrier groups. It was 1540 hours before one of his scout planes spotted the Japanese fleet 275 miles away. But now, Mitscher had an agonizing decision to make: If he waited till morning he might lose contact and the Japanese ships would escape during the night. If he launched an immediate attack, he could still hit Ozawa's fleet before darkness fell, but it meant that his planes would have to make their way home in darkness. Mitscher judged the opportunity worth the risk, turned TF 58 into the wind and launched a 216 plane strike.

The sun was low on the horizon when the American planes came upon the Mobile Fleet. Ozawa was able to put up only seventy-five planes from his new flagship, Zuikaku, but these were brushed swiftly aside, and in a short time, the carrier Hiyo was mortally hit and sinking; the Zuikaku was badly damaged and set ablaze, as was the light carrier Chiyoda. Battleship Haruna and heavy cruiser Maya were damaged. Sixty-five Japanese planes were lost, at a cost of 20 American. Two of Ozawa's oilers were sunk. Aware now that the damage reports which he had received regarding the American fleet were greatly exaggerated, Ozawa turned his remaining force westward, abandoning any thought of further combat.

Darkness falls rapidly in the Pacific and there was barely any light left and fuel was running low when the attacks ended. The American planes reformed above the shattered Japanese fleet to make their way home. As the returning American strike force approached their carriers in the dark, planes began to ditch from battle damage or lack of fuel. As the sound of their engines reached the ears of the waiting fleet, Admiral Mitscher, defying the possibility of lurking submarines, ordered all ships to turn on their lights. Besides the flight deck illumination necessary for night carrier landings, ships' running lights were switched on, and searchlights pierced the sky like beckoning fingers to the incoming pilots. Some ships even fired star shells to illuminate the area. Though most of the planes landed more or less safely, eighty planes crashed on the carrier decks or ditched near the TF for lack of fuel or a clear deck to land on. Mitscher's ships combed the waters that night and through the next day for survivors. All but 38 of the returning pilots were saved.

The elated Navy pilots dubbed the battle, "The Great Mariana's Turkey Shoot," and the two day score was impressive; three heavy Japanese carriers and 475 planes - 92% of Ozawa's aircraft, at a cost of 2 US oilers and 130 planes, including the 80 which splashed or crashed returning to the carriers. Four of Admiral Mitscher's ships had suffered minor damage; none were sunk or put out of action. Though, four months later, in Leyte Gulf, the Japanese Navy was finally destroyed, the Battle of the Philippine Sea, had irretrievably broken Japanese naval air power in the Central Pacific. The last "classic" carrier-vs-carrier battle of the Pacific War was over, and, by the 21st, Ozawa was out of striking range. That evening TF 58 turned back for the Marianas.

Ozawa's defeat meant that there would be no relief for Saipan, though the Japanese there were not aware of this for several days. Organized defense on the island had collapsed and the scattered remnants of Japanese units were isolated in hundreds of caves over the northern part of the island, being blown or burnt out one by one by the Marines. At the mouth of one of these caves at about 1000 hours on 6 July, Generals Saito Yoshitsugu and Keiji Igata, the Army commanders, committed ritual suicide, seppuku. Rather than beheading them, moments after they slit their bellies, as is customary, their seconds shot them in the back of the head. At about the same time, in another cave somewhere on the northern end of the island, Admiral Nagumo Chuichi, whose fleet had struck Pearl Harbor three years before, killed himself with a pistol. For him, the events he set in motion that day had come full circle.

Three days later, at 1615 hours on 9 July, Admiral Richmond Kelly Turner, who had commanded the landing force, announced that Saipan was secure. Almost the entire Japanese garrison of 25,469 soldiers and 6,160 sailors had died, along with nearly 22,000 civilians. The cost in American casualties was high; 14,111, including 3,126 dead, but the final cost would surely have been much higher had Admiral Ozawa succeeded in his mission.

-- Bud Wilson

Many thanks to Jim Meeks for introducing us to this story.!!