On 6 June, while the convoys carrying the attack troops headed westward for their staging bases in the Marshalls, Marc Mitscher’s Task Force 58 weighed anchor and slipped out of Majuro for waters east of the Marianas. For this operation Admiral Mitscher had gathered together a total of seven carriers, eight light carriers, seven fast battleships, three heavy cruisers, ten light cruisers, and fifty-two destroyers.
Their missions were to prevent Japanese aircraft from interfering with the capture of Saipan, Tinian, and Guam; to protect the expeditionary force and the troops ashore from attack by enemy surface vessels; and, commencing on D minus 3 (12 June), to destroy aircraft and air facilities in the Marianas. Finally, on 13 June when it was presumed that Japanese aircraft operating from fields in the Marianas would be eliminated, Task Force 58 was directed to destroy all other types of Japanese defenses both by aerial bombardment and by ships’ fire from its supporting vessels.
This was to be the culmination of an accelerated program of aerial neutralization of the Marianas. Mitscher’s fast carriers had raided the islands on 22-23 February, and a few bombs had been dropped in April on both Saipan and Guam by B-24’s of the Seventh Air Force escorting Navy photographic planes over those islands. For almost three months Army heavy bombers and Navy and Marine Corps fighters and dive bombers had steadily pounded Truk, the western Carolines, the Palaus, and Marcus and Wake Islands.
After the destructive carrier strike against Truk on 17 February, primary responsibility for neutralizing that base as well as sister islands in the Carolines fell to planes of the Seventh Air Force, stationed in the Marshalls, and the Thirteenth Air Force, based at Empress Augusta Bay, Bougainville Island, and later (early May) in the Admiralties. The neutralization plan had called for almost daily attacks, since Japanese runways could otherwise have been quickly repaired to accommodate replacement planes flown down through the chain of mandated islands. As the target day for Saipan approached, B-24 raids against Truk were stepped up sharply and other possible danger points in the Caroline’s were hit proportionately. Meanwhile, late in May Mitscher’s Task Group 58 had conducted a successful raid on Marcus and intervention from that direction in the forthcoming Marianas operation. Thus, with all possible routes of enemy aerial interception from the south, east, and northeast successfully interdicted, Task Force 58 was assured a relatively free hand to deal with Japanese airpower based on the Marianas themselves.
The original plan for the pre-invasion bombing of the Marianas called for the first Task Force 58 carrier strike to be launched at dawn of 12 June, three days before the scheduled landing. Because of unexpectedly good weather conditions en route, the escorting destroyers were fueled more rapidly than had been anticipated, and the entire force arrived at points within fighter range of its targets earlier than planned. This bit of good fortune induced Admiral Mitscher to request permission to launch his first fighter sweep on the afternoon of 11 June rather than wait until the following morning. His main reason was that all previous carrier attacks by Task Force 58 had been launched at dawn and that an alteration in the pattern would surprise the enemy and be that much more effective.
Admiral Spruance approved, and at 1300 on the 11th the first planes took off from the carriers, which at that time were approximately 192 miles northeast of Guam and 225 miles southeast of Saipan and Tinian, The results were altogether gratifying. Of the 225 planes launched in this initial fighter sweep, only twelve were lost. By contrast, the enemy suffered heavily. Estimates as to Japanese aircraft put out of operation either through destruction or serious damage ran from 147 to 215.
Ashore on Saipan a Japanese soldier, member of the 9th Tank Regiment, wrote of the strike in his diary: At a little after 1300, I was awakened by the air raid alarm and immediately led all men into the trench. Scores of enemy Grumman fighters began strafing and bombing Aslito airfield and Garapan. For about two hours, the enemy planes ran amuck and finally left leisurely amidst the unparalleled inaccurate antiaircraft fire. All we could do was watch helplessly. At night we went, to extinguish the mountain fires which had been caused by gun fire. They were finally brought completely under control.
In spite of the magnitude of the attack, the Japanese command on Saipan apparently did not realize on the 11th that this was the prologue to a full-size invasion. At 1600 on that date 43rd Division headquarters ordered the construction of a new road between the Marpi Point and Aslito airfields. The north-south highway already in use ran along the west coast adjacent to the ocean shore, and General Saito felt that in “the event of a battle occurring at the shore, there would be a great danger of the direction of the battle being hindered by an immediate interruption of communications.”
The new road was to be inland from the coast line and follow the comparatively well-concealed foot of the mountains. Nothing could illustrate more graphically the Japanese failure to grasp the fact that the 11 June bombing was not merely another hit-and-run strike but the beginning of an invasion. If it had suspected an immediate invasion, the Army command on Saipan would not have diverted to a long-range project when men and matériel that could and should have been devoted to emergency fortifications.
Though there was a wide discrepancy in the estimates of damage inflicted on the Japanese during the attack of 11 June, there was no doubt that the enemy’s power of aerial resistance in the Marianas had been considerably reduced. At no time thereafter were Japanese land-based aircraft more than a minor nuisance to American operations. According to Admiral Nimitz, “Control of the air had been effected by the original fighter sweep on 11 June.”
For the next three days (12-14 June) all four of Mitscher’s task groups flew scheduled strikes over Saipan, Tinian, Guam, Rota, and Pagan with the object of continuing the destruction of enemy aircraft, rendering airfields at least temporarily useless, destroying coastal defense and antiaircraft batteries, and burning cane fields south of Mutcho Point on Saipan to prepare for forthcoming troop landings. In addition, last-minute photographic missions were flown over all three of the larger islands. During this period another fifty planes were reported destroyed with an additional sixty-six put out of operation. The task groups were less successful in bombing enemy airfields. Few runways on these or any other outlying bases were surfaced with concrete, macadam, or steel strip since the comparatively light weight of Japanese aircraft made such expenditure of time and material unnecessary, and it proved almost impossible to render the earthen airfields permanently unserviceable by moderate bombing attacks.
The effectiveness of preliminary aerial bombardment of coastal defense and antiaircraft artillery is difficult to assess. Pilots reported direct hits on gun positions on all three islands, but the accuracy of these reports could not be precisely measured. The mere fact that enemy guns remained silent after a strike was no indication that they had been destroyed or even seriously damaged since the Japanese might have been holding their fire in order to save ammunition or avoid detection. Indeed, one dive bomber squadron leader after a run on Tinian admitted, “The odds of a dive bomber hitting a target the size of a gun are astronomical even under ideal conditions.” He concluded that, on the basis of photographs and observations, shrapnel and blast resulting from the bombing caused the chief damage to enemy installations, knocking out the control posts and damaging some of the guns.
On 12 June Admiral Mitscher’s carrier pilots came into an unexpected windfall in the form of two Japanese convoys trying to escape the area. One of these, composed of about twenty vessels and located about 125 miles west of Pagan on a northerly course, was immediately bombed and strafed heavily. Nine merchant ships, with a total tonnage of almost 30,000 tons, along with their escort vessels including one large torpedo boat, three submarine chasers, and a converted net tender, were sunk. On the same day, other carrier planes hit two cargo vessels just off the northwest coast of Saipan, sinking one and damaging the other so badly that it had to be beached. Still another was sunk while being repaired in Tanapag Harbor. On 13 June a convoy fleeing south of the west coast of Guam was struck by planes of Rear Admiral Joseph G. Clark’s Task Group 58.1. One high-speed transport was definitely sunk and other shipping was reported set on fire.
[NOTE2-5-13 JANAC, Japanese Shipping Losses, pp. 12, 60-61. Naval pilots mistook this torpedo boat, the Otori, for a destroyer and so reported it. (Van Wyen and Land, Naval Air Operations in the Marianas, p. C-27.) The error is understandable since the Otori, though less than half the size of a destroyer, resembled it somewhat in silhouette. Otherwise, American damage claims for this action erred on the side of modesty. Postwar studies indicated a total of fourteen ships sunk, whereas the official American Navy claim came only to ten. Van Wyen and Land, Naval Operations in the Marianas, p. C-27; JANAC, Japanese Shipping Losses, pp. 12, 60]
Also on 13 June, while the carrier planes continued their bombing and strafing missions against the islands, the fast battleships and certain designated destroyers were detached from escort and screening duties and assigned the mission of initiating naval shore bombardment of Saipan and Tinian and covering mine-sweeping operations.
Seven fast battleships and eleven destroyers were detached and formed into a separate bombardment group under command of Vice Admiral William A. Lee, Jr. From 1040 until about 1725 they pounded the west coast of Saipan and Tinian. Meanwhile, ten fast mine sweepers probed the waters off the west coast of Saipan from distances of about six to two miles offshore. They found no moored contact or acoustics mines and received no fire from the beach. That night the battleships withdrew, but five destroyers remained in the area to deliver harassing fire.
The results of the first day’s naval gunfire were doubtful. At the close of the day’s bombardment, headquarters of the 31st Army reported that although the city streets in Garapan and Charan Kanoa had been almost destroyed, personnel losses had been relatively slight. In spite of naval reports of considerable damage done to shore installations, General Holland Smith’s naval gunfire officers remained skeptical. In their opinion, the effectiveness of the firing by these ships of Mitscher’s task force had been limited because of severe handicaps. With one exception, the fast battleships had received no continuous training in shore bombardment as had most of the old battleships. This type of firing, which required slow, patient adjustments on specific targets, was quite different from that normally experienced in surface engagements and called for specialized training. Also, air spotters off the fast battleships had neither experience nor training in locating ground targets. Finally, because none of the ships was allowed to move closer than 10,000 yards (five nautical miles) from the shore for fear of mines, accurate fire against anything but large buildings and other such obvious targets was virtually impossible.
Nevertheless, to the Japanese on the island the bombardment of the 13th, and especially that of the naval vessels, was a terrifying experience. One soldier described it thus: At 0500 there was a fierce enemy air attack. I have at last come to the place where I will die. I am pleased to think that I will die calmly in true samurai style. Naval gunfire supported this attack which was too terrible for words. I feel now like a full-fledged warrior. Towards evening the firing died down but at night naval gunfire continued as before. About 1700 communications with battalion headquarters were cut off.
Another eyewitness, a Japanese naval officer, noted: “The shells began to fall closer and closer to the airfield. It was frightful. The workers were all rather depressed.” The same officer reported that shortly after the naval shelling started he ordered his lookouts, his fire-fighting unit, and his workers to withdraw to caves in the hills. He himself remained behind with a junior officer and a “superior petty officer.” “On the veranda of the destroyed workers’ quarters,” he notes, “we who had stayed behind bolstered our spirits with five bottles of beer.”
Early on the morning of 14 June, Rear Admiral Jesse B. Oldendorf arrived off the coast of Saipan with the two bombardment groups that would carry the main burden of naval gunfire support both before and during the seizure of the island. This force consisted of seven old battleships, eleven cruisers, twenty-six destroyers, and a few destroyer transports and fast mine sweepers. The battleships had all been commissioned between 1915 and 1921. Four of them, California, Pennsylvania, Maryland, and Tennessee, were survivors of the attack on Pearl Harbor. All had undergone the rigorous training program for shore bombardment set up by V Amphibious Corps at Kahoolawe Island in the Hawaiian Islands.
These ships were able to move into closer range than had the fast battleships in the previous day’s bombardment. Mine sweepers had reported the area to the seaward of two miles from the shore line free of mines and were steadily moving in closer to the reef line. Better results were reported from this day’s activities, and many installations were believed to have been directly hit, in spite of the facts that the time allowed for deliberate pinpoint fire was too short and that air spotters again revealed their lack of training in distinguishing important land targets.
There is evidence that this pre-invasion bombardment was especially effective against prepared gun positions of antiaircraft units, which were for the most part fixed. Two prisoners of war taken on 29 June reported that their antiaircraft unit, the 1st Battery, 25th AAA Regiment, had been annihilated before D Day in the Magicienne Bay area. The Japanese naval officer quoted above noted in his diary, “Practically all our antiaircraft gun and machine gun positions were destroyed by bombing and shelling on the 13th, 14th, and 15th.”
In other respects, however, the American preliminary bombardment was far from perfect. A Japanese artillery instructor, assigned to Saipan as an observer, managed to radio the following report on the effects of the shelling: Beach positions withstood four days of bombardment. Those observation posts and gun emplacements that were protected by splinter-proof shelters were able to withstand the bombardment. Dummy positions proved very effective. During bombardment, both day and night, movement to alternate positions was very difficult Communication lines were cut frequently, and the need for repairs and messengers was great.
During this naval bombardment of the 14th, two of the supporting ships were hit by fire from the shore. The destroyer Braine, while bombarding Tinian, took a 4.7-inch shell that caused three deaths and numerous injuries. The battleship California was struck by a small caliber artillery shell; one man was killed, nine were wounded, and the ship’s fire control system was damaged.
Also on the 14th, three naval underwater demolition teams reconnoitered the landing beaches of Saipan as well as other parts of the shore line. Each team consisted of about sixteen officers and eighty men, all naval personnel except for one Army and one Marine liaison officer per team. The men were dispatched from destroyer transports in small boats to the edge of the reef whence they swam close into the shore line in full daylight under the protection of ships’ fire. No obstacles were reported and hence no demolition work was necessary. The teams performed their work under considerable fire from the beach, but even so only two men were killed and fifteen wounded—a low figure considering the inherent danger of the operation and the fact that promised air support failed to materialize and ships’ fire was generally too far inland to provide much protection.
One result of the underwater demolition activities was to alert the Japanese on Saipan as to the probable place and time of the forthcoming landing. At 0800 a 31st Army message stated: “The enemy at about 0730 was making reconnaissance of reef with small boats. It is judged that the enemy will land here.” Later in the day another message from the same headquarters reported: Since early this morning the enemy small vessels have been planting markers and searching for tank passages on the reef. Because as far as one can see there are no transports, the landing will have to be after tonight or dawn tomorrow. The enemy bombardment is being carried out on coastal areas in anticipation of a landing.
D-Day Bombardment and Ship-to-Shore Movement
On the night of 14-15 June most of the support ships retired, leaving a handful to continue harassing fire along the coast line. Meanwhile the Western Landing Group, commanded by Admiral Hill and consisting mostly of transports and LST’s carrying the 2nd and 4th Marine Divisions, was slowly approaching the island from the east. As dark fell the marines could observe fires burning ashore and the glow of star shells fired by the naval ships left in the area. Shortly after 0500 the gigantic convoy moved into the transport area off the west coast of Saipan. In the early dawn, Mount Tapotchau lay silhouetted in the east. Streaks of fire from the armada of naval support ships colored the sky and the shore was blurred in a haze of smoke and dust. As the light improved, the town of Charan Kanoa became visible. To the north lay Garapan, the capital city. In its harbor, called Tanapag, lay several Japanese ships, beached, half-sunken, and smoking.
Naval bombardment commenced about 0530. Heavy close support ships were ordered not to approach closer than 1,500 yards from the reef. Destroyers were permitted to move in as far as 1,000 yards. Two old battleships, two cruisers, and seven destroyers were assigned the duty of last-minute preparation of the landing beaches themselves. At dawn these ships took station and shortly thereafter the two battleships commenced main battery fire at the beach defenses; less than an hour later the two cruisers opened up with their 12-inch guns.
In spite of the apparent intensity of this barrage, the Japanese high command was not overly impressed—at least not officially. From 31st Army headquarters came the report: “They did not carry out large scale shelling and bombing against the positions on the landing beach just prior to landing. When they came to the landing, even though we received fierce bombing and shelling, our basic positions were completely sound.”
But to other less exalted defenders of the island, the shelling appeared more formidable. One member of the 9th Tank Regiment observed fairly effective results from the shelling of the Magicienne Bay area. A naval supply warehouse was hit, causing a considerable number of casualties, and a nearby ammunition dump was set off. “There was no way,” he reported, “of coping with the explosions. We could do nothing but wait for them to stop.” Somewhere in the same vicinity, the Japanese naval officer mentioned above took to the bottle again to calm his nerves against the shock of the shelling, “I quietly opened the quart I brought along,” he noted in his diary, “and took my first ‘shot’ from it. There is something indescribable about a shot of liquor during a bombardment.”
At 0545 the word was passed throughout the American task forces that H Hour, the moment at which the first troops were supposed to land, would be 0830, as scheduled. Guns and winches were manned; boats were lowered into the water from the transports.
Shortly after 0700 the thirty-four LST’s carrying the Marine assault battalions moved into position and dropped anchor about half a mile off the line of departure. The line, the starting point from which the assault landing craft would take off, was located 4,250 yards offshore. Bow doors swung open; ramps lowered, and hundreds of amphibian tractors and amphibian tanks crawled into the water and commenced to circle. In all, 719 of these craft would be employed in the operation.
Astern of the assault landing ships lay twelve other LST’s carrying light artillery, most of which would be landed in DUKW’s. Still further seaward of each division’s beach lay two dock landing ships embarked with heavier landing craft (LCM’s) that would take ashore the tanks and heavy artillery as soon as enough beachhead had been secured by the infantry. About 18,000 yards offshore the larger troop transports swung at anchor. Aboard were reserve troops, headquarters troops, shore party teams, heavy artillery, trucks, tractors, bulldozers, and sundry equipment and supplies.
Meanwhile, north of the main transport area, marines of the 2nd Regimental Combat Team (2nd Marine Division) and the 1st Battalion, 29th Marines, were conducting a diversionary demonstration off the town of Garapan. Boats were lowered, troops embarked, standard waves were formed and went in as far as 5,000 yards off the beach. There they circled for ten minutes without receiving any fire and then returned to their mother ships.
Off the main landing beaches, all ships’ fire ceased at 0700 to allow a thirty-minute Strike by carrier planes. Fifty fighters, 51 scout bombers, and 54 torpedo bombers conducted an area bombing attack along the beaches with the primary aim of demoralizing the enemy rather than knocking out particular installations. As soon as this strike lifted, the naval ships assigned to close support took up the course once again and continued to hit the beaches with heavy guns until the first wave of troops was only 1,000 yards from the shore line and with 5-inch guns until the troops had progressed to within 300 yards.
The line of departure was marked by four naval patrol craft (PC’s), each anchored and flying flags designating the number and color of the beaches opposite them. At 0750, H Hour was postponed to 0840 because of a delay in launching the amphibian tractors. Small control craft escorted the leading waves toward the line of departure. A few minutes after 0800 the control craft hoisted their Wave-1 flags and twenty-four LCI gunboats crossed the line of departure, firing their automatic weapons as they went.
About five minutes later wave flags were run down from the signal yardarms of the anchored patrol craft and the first wave of amphibian tanks and tractors crossed the line of departure. Following waves—three for the northern beaches and four for the southern—were spaced at intervals of from two to eight minutes. The run into the beach would take a few minutes less than half an hour at maximum LVT(A) speed of 4.5 knots.
About 1,600 yards from shore the gunboats on the northern beaches stopped engines and lay to just short of the reef but kept up their fire as the first wave passed through them. On the southern beaches, where the reef was closer to the shore, the LCI(G)’s moved in to 400 yards and let loose salvos of 4.5-inch rockets in a last minute saturation of the beach. As the leading troops came within 300 yards of the shore, all naval gunfire ceased except in the area around Afetna Point, which lay between the two divisions’ beaches. A last-minute strafing attack by seventy-two carrier-based planes commenced when the leading waves were 800 yards from the shore line, continued until the first troops were within 100 yards of the beaches, then shifted to 100 yards inland until the first landings were made.
[NOTE 35 LCM—landing craft mechanized—a shallow draft vessel, fifty feet long, equipped with a bow ramp and primarily designed to carry a tank or motor vehicles directly onto the beach.]
The formation of the assault waves differed between the two Marine divisions. North of Afetna Point, the 2nd Marine Division was landing with four battalion landing teams abreast. From north to south (left to right) the 6th Marines headed for Red Beaches 2 and 3; the 8th Marines for Green Beaches 1 and 2, immediately in front of the Charan Kanoa airstrip. South of Afetna Point, the 4th Marine Division proceeded toward Blue and Yellow Beaches with the 23rd Regimental Combat Team on the left and the 25th on the right.
In the 2nd Marine Division’s zone the first wave consisted of eight separated lines of six amphibian tractors, each in line a breast formation. Between each line of six LVT’s was echeloned one platoon of amphibian tanks (LVT(A) (4)’s) mounting 75-mm. howitzers. The succeeding three waves consisted of LVT’s alone in line abreast. The amphtracks (LVT’s) were crewed by the Marine’s 2nd Amphibian Tractor Battalion and the Army’s 715th Amphibian Tractor Battalion. The amphibian tanks, seventy in number, belonged to the Marine’s 2nd Armored Amphibian Battalion.
The 4th Marine Division’s landing plan differed. The first wave consisted exclusively of sixty-eight amphibian tanks, formed abreast and manned by the Army’s 708th Amphibian Tank Battalion. Most of these were old style LVT(A)(1)’s with only a 37-mm. gun on the bow, but sixteen of them were LVT(A)(4)’s carrying 75-mm. howitzers. Astern in four successive waves came the assault troops boated in amphibian tractors of the Marine 10th Amphibian Tractor Battalion (less Company A, plus Company C, 11th Amphibian Tractor Battalion) and the Army 773rd Amphibian Tractor Battalion.
From the line of departure to the reef the first waves moved in good order and met only moderate enemy gunfire. Once across the reef, however, the picture changed. All along the line the Japanese opened up with automatic weapons, anti-boat guns, and artillery and mortar barrages against the first wave. These increased in intensity as the second, third, and fourth waves climbed over the reef.
In the 2nd Marine Division’s zone, three amphibian tanks and four tractors were knocked out of action between the reef and the beach.39 Surf in the area ran as high as twelve to fifteen feet, too high for amphtracks to operate with any great degree of safety. Nevertheless, only two capsized as a result of the swells. About 98 percent of all the tractors got ashore safely.
Once across the reef, the wave formation in the 2nd Division area broke down completely. Because of their superior speed, many of the tractors commenced to overtake their supporting amphibian tanks and to compress them from echelon almost into column formation. Some tractors crossed in front of the tanks thus masking their fire.
Even more serious, the Navy guide boat led the leading waves off course. This has been variously attributed to compass error, a strong drift of current to the northward, and the fact that extremely heavy fire was coming at the boats on the right flank from the area around Afetna Point. Whatever the reason, the entire right flank of the leading waves veered to the left, thus causing a northerly shift along the entire line and considerable crowding in the center.
The 2nd Battalion, 8th Marines, which was scheduled to land on Green Beach 2, went ashore instead on Green 1, where it became badly intermixed with the 3rd Battalion of the same regiment. The two assault battalions of the 6th Marines landed about 400 yards north of their assigned beaches, Red 2 and 3.
The first assault waves of the 8th Marines landed on the Green Beaches at approximately 0843; the last were being landed by 0900. On the Red Beaches the first assault wave landed at 0840, the last at 0908.
To the south, in the area of the 4th Marine Division, the ship-to-shore movement was proceeding somewhat more smoothly. Here, the sixty-eight amphibian tanks of the Army’s 708th Amphibian Tank Battalion constituted the entire first wave. All commenced to fire 75-mm. howitzers or 37-mm. guns about 400 yards from the shore after mounting the reef. From each beach came answering fire of all types including mortar, small arms, and artillery. Japanese artillery markers—small flags on bamboo sticks that were apparently a part of the enemy’s prearranged fire plan and for unknown reasons had not been removed by underwater demolition teams on the previous day—were scattered along the reef. Of the sixty-eight tanks in the first wave all but three arrived safely. One burned, one was swamped on the reef, and one received a direct hit from an antitank weapon firing from the shore at about twenty-five yards range.[N2-5-42]
Astern of the tanks came the amphibian tractors of the Marine 10th Amphibian Tractor Battalion and the Army 773rd Amphibian Tractor Battalion in four waves, spaced from two to six minutes apart. Of the 196 troop-carrying tractors, only two failed to land their cargo; one was hit by a shell on the reef and the other developed mechanical difficulties. Between 0843 and 0907 all of the leading waves with about 8,000 marines embarked were ashore.
[N2-5-42 1st Lieutenant Russell A. Gugeler, FA, 1st I and H Sv, Army Amphibian Tractor and Tank Battalions in the Battle of Saipan, 15 June-9 July 1944, 20 Jan 45, pp. 6-7, MS in OCMH. These figures differ from those given in the official action report of the 708th Amphibian Tank Battalion, which states that two of its tanks were overturned and three lost due to maintenance difficulties. The report mentions no direct hits. (NTLF Rpt Marianas, Phase I, Incl H to Incl Y, p. 1). The former figures are accepted as more accurate because the author of that account gives a detailed description of the LVT(A) casualties in the battalion as well as the names and actions of the personnel involved.]
Breakdown of the Landing Plan
From the outset, two factors marred the smooth execution of the landing plan. The first was the wide gap that had developed between the right battalion (2nd Battalion, 8th Marines) of the 2nd Marine Division and the left battalion (3rd Battalion, 23rd Marines) of the 4th Marine Division. The landing plan had provided for a gap between the two divisions. Troops were not to land on Afetna Point itself because of the reasonable fear that the enemy would have placed his heaviest concentration of artillery there to guard the only channel through the reef to the pier at Charan Kanoa. However, the distance between the two divisions was more than double that envisaged because the 2nd Battalion, 8th Marines, landed north of its assigned beach. Almost three days would elapse before firm contact between the divisions was established.
Perhaps more serious was the breakdown of the scheme to employ amphibian tanks and tractors to carry the assault inland from the water’s edge. The basic plan for the landing on Saipan prescribed a blitz assault, continuous from shipboard inland to the first high ground. In the 2nd Marine Division’s zone of action the four companies of amphibian tanks were to proceed inland about three hundred yards to the tractor control line, cover the debarkation of the assault troops from their tractors, and support their advance to the first objective line, which lay about 1,500 yards inland. Tractors of the first wave were to accompany the LVT(A)’s to the tractor control line and there debark their troops. The succeeding three waves were supposed to discharge their troops on the beach.
In the zone of the 4th Marine Division, the initial wave—amphibian tanks—was to lead the next two waves—tractors—all the way to the first objective line, which was located on the first high ground a mile inland. There, the tanks would deploy and support the troops as they debarked and moved forward. The fourth and fifth waves were to be discharged at the beach and mop-up areas bypassed by the leading waves.
None of these plans succeeded completely, and for the most part the scheme of
employing amphibian tanks as land tanks and amphibian tractors as overland troop-carrying vehicles must be marked off as a failure. The LVT(A)’s had neither the armor nor the armament to withstand the terrible pounding from enemy artillery and supporting weapons that could be expected during this phase of the assault Moreover, the LVT(A)’s were underpowered and were stopped by sand, trenches, holes, trees, and other minor obstacles, most of which a land tank could have negotiated with ease. Once the tractors were out of the water, their hulls were exposed and they became easy targets for enemy fire, which their armor was too light to resist. On shore they were clumsy and slow. It proved far healthier for troops to extricate themselves from these death traps as fast as possible and find shelter in whatever natural protection the terrain and the vegetation offered.
On the 2nd Marine Division’s beaches the situation rapidly became chaotic. Trees, trenches, and shell holes stopped some of the tanks of the 2nd Armored Amphibian Battalion before they could even cross the beach. Between the beach and the tractor control line, twenty-eight LVT(A)’s, more than one-third the total number, were disabled.
Only a few points of ingress from the beach inland could be discovered, and while the amphibian tanks were maneuvering up and down trying to locate the points they became almost hopelessly intermixed with the tractors of the first and succeeding waves. Up to the tractor control line infantry troops were able to maintain close contact with the tanks, but the eighteen LVT(A)’s that went beyond that point got little infantry support. Tanks fired indiscriminately among troops and tractors and in general merely added to the confusion instead of aiding the battalions they were supposed to support.
Congestion was particularly bad in the area of Green Beach 1, where the two battalions of the 8th Marines were trying to land at the same time because the right flank of the first wave had veered to the left. These troops were all embarked in the amphibian tractors of the 715th Amphibian Tractor Battalion. Directly ahead of them was a heavily wooded bank constituting an almost impassable barrier for tanks and tractors alike. The marines forthwith abandoned their tractors and took cover behind the embankment. Within five minutes after the first wave touched shore, the second wave arrived and landed a little to its right. By the time the third and fourth waves had landed, the men on foot were being squeezed between the tractors to their rear and the Japanese to the front. Altogether, only two tractors were able to get beyond the beach, one making its way as far as the radio tower 700 yards inland. Two days later, the driver wandered back to the beach but was too shell-shocked to be able to remember how he had got that far or what had happened when he got there. On the southern beaches, the 708th Amphibian Tank Battalion fared a little better.
Of the sixty-eight tanks in the first wave, about half reached Fina Susu ridge by ten o’clock. Contrary to expectations, progress through the town of Charan Kanoa was fairly easy, and by 0915 thirteen tanks of Company B, assigned to this sector, had arrived at the objective. South of them the going was more difficult. The tanks that landed below Charan Kanoa had to fight swamp ground, tank trenches, heavy artillery, a burning gas dump, and a steep railroad embankment before attaining the ridge. Nineteen made it. Those on the extreme right had the most difficulty. Swinging south, three tanks reached the tip of Agingan Point about a thousand yards south of the lowest landing beach. They braved it out against fairly heavy Japanese mortar and artillery fire, but when American naval shells commenced to drop in the area they discreetly withdrew. Agingan Point would have to wait another day for capture.
Meanwhile, back on the beaches most of the troops were deserting their amphibian tractors for the dubious safety of traveling on foot and belly. The 23rd Marines, which landed in and just south of Charan Kanoa, made fair progress inland. Fifteen LVT’s of the second wave were able to carry their troops through the town itself and on to the ridge behind. On the beach immediately below, thirty-three tractors got as far as a railroad embankment about 400 yards inland before the infantry commanders ordered their troops to debark.
On the southern (Yellow) beaches, where the fighting was fiercest, no such progress was made. One company of the 773rd Amphibian Tractor Battalion got as far as a railroad spur about 700 yards inland, but the rest unloaded their troops as rapidly as possible and shoved off back to the transfer line beyond the reef. In spite of the hasty withdrawal of most of the first group of LVT’s, the shore line soon was thick with tractors as succeeding waves telescoped onto the beach. It was small wonder. After a full hour’s fighting the 1st Battalion, 25th Marines, had succeeded in pushing just twelve yards in from the beach, and the 2nd Battalion’s progress was only a little better. The tractor plan failed most signally here. The infantryman was on his own.
Expanding the Beachhead: Action of the 2nd Marine Division
On the Red Beaches to the north, the two assault battalions of the 6th Marines met fierce enemy fire immediately upon landing. The failure of most of the amphibian tanks and tractors to proceed any considerable distance inland and the rain of enemy shells caused unexpected congestion and confusion on the beaches. The command posts of both battalions received direct hits that seriously injured battalion commanders and most of their staffs. The regimental commander, Colonel James P. Risely, USMC, came ashore at 1000 and established his command post practically at the water’s edge. Forty minutes later the regimental reserve (1st Battalion, 6th Marines) commenced to land and prepare to support the assault elements.
By 1105 the front line had advanced only 400 yards inland. The 3rd Battalion, on the right, was suffering especially heavy casualties, and the 1st Battalion was therefore ordered to pass through the 3rd. Weak points began to appear all along the line. More serious, a dangerous gap developed between the right flank of the 6th Marines and the left flank of the 8th Marines when the 6th Marines landed some 400 yards north of its assigned beaches. In spite of the fact that Companies K and L of the 6th Regiment were ordered to establish physical contact, a gap of 300 yards still existed, although covered by fire. Around noon the 6th Regiment’s casualties had mounted to an estimated 35 percent.
An hour later three Japanese tanks counterattacked in the area in front of the command post. Two of the tanks were knocked out by bazookas before penetrating the front line, but the third managed to push through to within seventy-five yards of the command post before being disabled by a bazooka rocket fired from the post itself. During the morning and early afternoon the regiment had no supporting weapons ashore other than those carried as organizational—bazookas, antitank grenades, and 37-mm. guns. Meanwhile, however, some tanks had commenced to land.
Shortly after 0900 a pilot tank was disembarked at the reef’s edge to explore the best passage through the reef. By 1020 it had searched out a path to Green Beach 1, although it was under heavy fire all the way. Once on the beach, enemy fire forced the crew to abandon the tank, but a reef route was marked and by 1300 the first of the 2nd Division’s tanks had landed on Green 1 and moved northward to support the 6th Marines. By midafternoon those tanks assigned to the 8th Marines had successfully landed and were in operation. Southward, on the Green Beaches, the chief problems facing the 8th Marines were confusion and congestion. The right flank battalion (the 2nd) had landed from 700 to 1,000 yards north of its assigned beaches.
As a result, the two assault battalions of the 8th Marines and part of one battalion of the 6th Marines all found themselves in the same beach area. To add to the confusion, the commanders of the two assault battalions of the 8th Marines were both wounded early in the action and had to be evacuated. The 2nd Battalion, 8th Marines, had the most difficult job—to attack south along the beach toward Afetna Point.
The object was not only to remove the menace of anti-boat weapons located in that area but also to secure the single reef channel off Charan Kanoa and permit the early entry of tank-carrying landing craft, which could not negotiate the reef itself. According to their prescribed scheme of maneuver, one company (Company G) moved south along the beach and the other two (E and F) fanned out to the southeast.
Company G was heavily armed with shotguns in addition to its normal weapons. These short-range guns with wide dispersion patterns were allotted to Company G chiefly as insurance against its firing into the lines of the 4th Marine Division toward which it was advancing. Progress was slow —the beach itself was thickly covered with pillboxes, and enemy riflemen situated east of the Charan Kanoa airstrip made the most of the flat, open terrain to harass the company’s left flank as it inched southward. At 0950 the 1st Battalion, in regimental reserve, was ordered to land. Company B was attached to the 2nd Battalion to support Company G’s attack toward Afetna Point. Companies A and C were committed between the 2nd and 3rd Battalions.
Later in the afternoon, the 1st Battalion, 29th Marines, was landed and also attached to the 8th Marines on the Green Beaches. Because of a shortage of amphibian tractors, the battalion was unable to boat up properly and hence landed in considerable disorder. Company B, 29th Marines, was ordered to proceed at once to fill a gap between Companies E and G of the 8th Marines.
However, its knowledge of the terrain was inaccurate and it was furnished no guides, so the company ended up about 600 yards north of its assigned position. The gap between the two right companies of the 2nd Battalion, 8th Marines, still remained unfilled, and Company A, 29th Marines, was ordered at 1730 to take that position. The approach of darkness and a heavy barrage of enemy artillery pinned these troops down before they could arrive at their destination.
Meanwhile, the 2nd Marines, which had participated in the demonstration off Tanapag, was beginning to come ashore on Red Beach 2. By 1800 the 3rd Battalion had landed and was attached to the 6th Marines, taking station before nightfall on the division left flank. By nightfall one company from the 2nd Battalion, 2nd Marines, in addition to the regimental commander and the advance echelon of his command post, was also ashore. The rest of the regiment was ordered to return to the area of the control vessel on the line of departure and remained boated throughout the night, to be landed by midmorning of the following day.
By noon of D Day Red Beach 3 was sufficiently clear to permit shore parties to land. The first team came ashore at 1300, and supplies began to flow over the two central beaches. Two more shore parties landed before the end of the day. Late in the day the two 75-mm. pack howitzer battalions of the 10th Marines were ashore and in position to support the infantry.
The 1st Battalion landed by 1403 and supported the 6th Marines; the 2nd Battalion was ashore at 1730 and in position to support the 8th Marines. Before dark the 2nd Marine Division’s commander, General Watson, had established his command post on Red Beach 2. By this time the division was digging in for the night and consolidating its positions against counterattack. Amphibian tanks and tractors had set up a defensive net against possible counteramphibious attacks from the sea. Division casualties were estimated to amount to 1,575—238 killed, 1,022 wounded, and 315 missing in action.
Action of the 4th Marine Division South of Afetna Point, the 4th Marine Division was having it own share of problems. To be sure, opposition in the town of Charan Kanoa was comparatively light. Japanese riflemen sniped away as troops and tractors moved through the rubble of the town, but they caused small damage.
The 3rd Battalion, 23rd Marines, reached the first objective line with phenomenal speed. On its right flank, however, the 2nd Battalion of the same regiment was not so lucky. Troops debarked from their tractors unevenly and there was no semblance of a continuous line. Fighting degenerated into a series of small unit actions, and not until midafternoon was tactical control regained by the battalion commander. The farther south, the worse the situation became. After a full hour, the 25th Marines had penetrated only twelve yards in from the beach. From its right flank the 1st Battalion caught the heaviest load of fire from pillboxes and mortars on Agingan Point. Amphibian tanks, bombs, and naval shells were unable to abate this nuisance for the remainder of the day, and at nightfall the 1st Battalion, 25th Marines, had to dig in with its right flank exposed.
Tanks of the 4th Marine Division began to come ashore about two hours after the initial landing. Their progress from ship to shore was seriously impeded since the channel off Afetna Point was still interdicted by enemy fire, thus making it necessary in most cases for tanks to debark from landing craft at the reef and attempt to negotiate the lagoon under their own power. Mounting seas during the afternoon increased the hazards of the trip. Of the sixty tanks of the 4th Tank Battalion, twenty-one failed to reach the 4th Marine Division’s beaches. One sank with the LCM on which it was boarded, another settled into a pothole off the reef, others were unable to locate landing craft to take them ashore or had their wiring systems fouled en route. Finally, six medium tanks were misdirected to Green Beach 2, a 2nd Division beach. Of these, five were immobilized in deep water inside the lagoon and the sixth was appropriated by the 2nd Division and failed to reach its parent organization until several days later. The only decisive tank action on the southern beaches occurred on the extreme right flank. There, the 1st Platoon of Company A helped to break up a counterattack that, if successful, would have driven the 1st Battalion, 25th Marines, back into the sea.
In the matter of artillery, the 4th Marine Division was more fortunate than the 2nd Division. Whereas the latter got only two battalions of 75-mm. pack howitzers ashore on D Day, the entire 14th Regiment, consisting of two 75-mm. pack howitzer battalions and three 105-mm. howitzer battalions, was landed by 1630 to support the 4th Marine Division. Shortly thereafter the reserve regiment, the 24th Marines, landed and proceeded to an area about 800 yards south of Charan Kanoa.
At 1930 General Schmidt, commander of the 4th Division, came ashore. His command post was a series of foxholes about fifty yards from the beach and very poorly protected from enemy light artillery, which was firing from the high ground about 1,500 yards away. General Schmidt later recalled, “Needless to say the command post during that time did not function very well. It was the hottest spot I was in during the war, not even excepting Iwo Jima.”
By the time the division commander had landed, the division’s left flank had been pulled back to conform to the configuration of the remainder of the line. The 2nd and 3rd Battalions, 23rd Marines, were both ordered to withdraw to positions roughly 800 yards west of the first objective line on the reverse slope of Fina Susu ridge. The movement was executed under cover of darkness—a difficult operation but one carried out successfully and without alerting the enemy. After the withdrawal was completed, the 1st Battalion relieved the 3rd, and the latter assembled in what was euphemistically called a “rear area” to protect the left flank.
Summary of the Situation at Nightfall By darkness of the first day it could be concluded that the landing was a success, even though only about two thirds of the area within the first objective line was under the marines’ control. In spite of the failure of the initial plan to carry some of the assault waves 1,500 yards inland aboard amphibian tractors, the troops had established a beachhead approximately 10,000 yards in length and over 1,000 yards in depth in most places. Two divisions were ashore with almost all their reserves. Seven battalions of artillery had landed, as had most of the two tank battalions. Both division command posts were ashore by the time the troops had dug in for the night. The most serious weaknesses in the Marine position were on its flanks. Afetna Point, between the two divisions, was still in enemy hands. So was Agingan Point on the right flank, and the 6th Marines’ hold on the extreme left was precarious.
As for the Japanese, they had exacted a heavy toll—how heavy cannot be accurately stated because of the inadequacy of casualty figures for D Day. The American landings had been made against what the enemy considered his strongest point and at a time when his garrison there was four battalions over strength. He had registered the landing area, using flags on the reef for registration markers, and as successive waves landed artillery and mortar fire increased in intensity. The Japanese had massed at least sixteen 105-mm. howitzers and thirty 75-mm. field pieces on the first high ground and the reverse slope thereof about 1.5 miles southeast of Charan Kanoa. Directly east of the airstrip they had emplaced a 150-mm. howitzer battery of four weapons with a similar battery south of it. All of these weapons were well sited, and they were responsible for a tremendous amount of fire on the landing beaches.
Although the enemy realized that the diversionary maneuver off Tanapag was a ruse, he did retain one infantry regiment (the 135th) in that area instead of committing it, as was intended, to the south of Garapan. At no time on D Day did the Japanese employ infantry in any great strength. They relied almost entirely on artillery, heavy weapons, and scattered tank attacks.
In the opinion of Holland Smith’s operations officer, the “most critical stage of the battle for Saipan was the fight for the beachhead: for the security of the landing beaches, for sufficient area into which troops and heavy equipment could be brought, and for the ability to render logistical support to those forces once landed.” This, to be sure, could be said of any amphibious landing where strong opposition is encountered. On Saipan, it was six days before the beachhead could be considered completely secured, but it was the first day’s action that was crucial. The most critical stage of “the most critical stage” was past.
SOURCE: Campaign in the Marianas; BY: Philip A. Crowl (United States Army Center of Military History)
World War Two: Saipan (2-6); Capture of Aslito Airfield
World War Two: Marianas(2-4); Prewar Japanese Activities