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Chapter 19: The Palaus and Morotai: Strategic and Tactical Planning

The Strategic Setting

The capture of the Sansapor–Mar area and the development of airfields there was the last significant offensive undertaking executed by Southwest Pacific Area forces in the Dutch New Guinea region, and with this operation the campaign in New Guinea and the offshore islands was strategically, if not tactically, completed.1 Some 650 miles of Japanese-dominated islands and sea areas lay between the Vogelkop Peninsula and the first objective in the Philippines—Mindanao—toward which forces of the Central Pacific were also preparing to move. While the Sansapor operation had been going on, troops under Admiral Nimitz’ control had completed occupation of the Mariana Islands and had begun making ready for the seizure of the Palaus and other islands in the western Carolines.

General MacArthur’s Planning

General MacArthur’s plans called for an advance to the Halmahera area, about midway between the Vogelkop and Mindanao, on 15 September, and Admiral Nimitz planned for his forces to invade the Palaus on the same day. The premises upon which an advance to the Halmahera region were based are clear. First, an air base between the Vogelkop and Mindanao would be necessary to provide left (south) flank protection against whatever air power the Japanese could bring to bear from Ambon, Ceram, and the Celebes against Allied forces advancing to Mindanao. Second, the Halmahera air base would be needed to provide land-based air support for the invasion of Mindanao which, in mid-June, General MacArthur tentatively rescheduled to begin on 25 October.

Because it would be impossible to secure prolonged carrier-based air support for operations ashore in the Halmahera region, the target area there had to be within range of fighters and medium bombers based at Sansapor. If, before the Halmahera operation

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were undertaken, it appeared that these aircraft and longer-range planes from Biak, Noemfoor, and Darwin, Australia, could not sufficiently reduce Japanese air power at Ambon, Ceram, and the Celebes to assure the safety of Allied forces ashore in the Halmahera area, then the Arafura Sea islands might have to be seized also. By June General MacArthur was beginning to change his mind about the necessity for seizing air bases in the Arafura groups, especially since the occupation of those islands might delay the advance to Halmahera. Ultimately the Allied Air Forces proved capable of neutralizing the Japanese air power in the Ambon–Ceram–Celebes area, and plans to seize the Arafura islands were canceled. The Japanese there remained undisturbed except by air raids until the end of the war.

While the range from Sansapor was an important factor in the choice of a target in the Halmahera region, other considerations also influenced the final decision. The target had to provide adequate space for airdrome development and a base area for light naval vessels such as PTs. Finally, the objective area had to be a location not too strongly held by the Japanese, so that in seizing it General MacArthur would not have to commit such large forces that the invasion of Mindanao might be delayed.

The requirements limited the choice to northern Halmahera Island or Morotai Island, lying about twenty-five miles off the northern end of Halmahera. Since available intelligence indicated that a strong Japanese combat garrison was on Halmahera, the capture of that island would involve a larger force than General MacArthur was willing to commit. Moreover, northern Halmahera could be subjected to Japanese counterattacks from both land and sea. On the other hand, Morotai Island was thought to be but lightly defended. Available information indicated that Morotai had ample space for airdrome and light naval base facilities. The Japanese could not reinforce the island by barge traffic once Allied Naval Forces’ PTs and Allied Air Forces’ planes began operations from Morotai bases. After consideration of all these factors, General MacArthur, in mid-July, decided that the objective in the Halmahera region would be Morotai.2

While General Headquarters, Southwest Pacific Area, was selecting Morotai as the target in the Halmahera region, the Joint Chiefs of Staff requested General MacArthur and Admiral Nimitz to submit comments on the possibility of accelerating the Pacific war by moving forward all current target dates or bypassing selected objectives (including Halmahera, the western Carolines, and the Philippines) in favor of direct jumps to either Formosa or the Japanese home islands.3

Neither General MacArthur nor Admiral Nimitz was willing or able to give approval to such proposals. General MacArthur, who felt that bypassing the Philippines would be tantamount to abandoning those islands, believed

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that a move to Formosa would be impossible until land-based air support was available in the northern Philippines, and he then considered a direct move to Japan impracticable.4 Admiral Nimitz, like General MacArthur, pointed out that logistic and tactical problems made it impossible to assure meeting current target dates for scheduled operations, and he felt that Southwest Pacific air forces would have to be firmly established in Mindanao before any attempt could be made to move to Formosa. At the same time, he believed that General MacArthur’s hope of reaching Mindanao by 25 October was too optimistic.5 At the Joint Chiefs’ level, further proposals for radical revisions in the schedule of operations for the Pacific were dropped, pending developments in the general situation in General MacArthur’s and Admiral Nimitz’ areas.6

Admiral Nimitz’ fears concerning the optimism of the 25 October target date for the invasion of Mindanao were well founded, a point also realized by General MacArthur. During conferences at Pearl Harbor in July, called at the suggestion of Admiral Nimitz to coordinate Southwest and Central Pacific plans for the Morotai, Palau, and Mindanao operations, Southwest Pacific planners learned that less amphibious craft and assault shipping could be made available to them than had previously been anticipated. Moreover, restudy of range and weather factors made it appear somewhat risky to depend upon the ability of Morotai-based aircraft to provide air support for Southwest Pacific forces on Mindanao after carriers had to leave the latter area and before airdromes could be developed there. To obtain adequate land-based air support for the Mindanao invasion force, General MacArthur returned to discarded plans to seize air-base sites on the Talaud Islands, about equidistant from Morotai and Sarangani Bay, Mindanao, where the first landings in the Philippines were then scheduled to take place. The employment of amphibious means for the Talaud operation would delay preparations for Mindanao, as would the development of airdromes on the Talauds. Finally, to have the invasion of Mindanao take place much before the middle of November would involve a conflict in timing with anticipated employment of assault shipping and carrier support by Admiral Nimitz for the occupation of Yap and Ulithi in the western Carolines, an operation scheduled for the first week in October. General MacArthur therefore revised his program to call for the invasion of Morotai on 15 September, the Talauds on 15 October, and Mindanao on 15 November.7

Central Pacific Plans

Admiral Nimitz’ plan to secure Yap and Ulithi was part and parcel of his program

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for securing air and naval bases in the western Carolines to assure the neutralization of Truk and to co-operate with Southwest Pacific forces in gaining control over the eastern approaches to the Luzon–Formosa–China coast region, the strategic target area designated by the Joint Chiefs of Staff. Originally, Admiral Nimitz’ planners contemplated the seizure of the entire Palau Islands group, a reef-bound chain that extends about seventy-seven miles in a north-northeast to south-southwest direction and is twenty miles across at its widest point.8

But operations in the Marianas were taking longer than expected, employing troops, shipping, and supplies needed for the Palau operation. This fact, coupled with information that the enemy garrison in the Palaus was being greatly increased, prompted Admiral Nimitz to abandon plans for seizing the entire group. Instead, the three largest islands in the southern section—Angaur, Peleliu, and Ngesebus—would be taken; the other islands would be neutralized; and, finally, Kossol Passage, near the northern end of the chain, would be secured as an emergency anchorage. Thus, time and forces would be saved, for it would be unnecessary to invade the Japanese strongholds in the central section of the archipelago. On Angaur and Peleliu, and possibly on Ngesebus, airdromes would be developed to extend Allied control over the western Pacific and support the invasion of the Philippines.

To secure an additional airfield to aid in maintaining control over the western Pacific and in neutralizing the central Carolines, Admiral Nimitz decided to seize Yap Island, which lies about 300 miles northeast of the Palaus. The occupation of Yap would have the additional advantage of denying to the Japanese air and submarine base facilities there. Since Kossol Passage, in the Palaus, would not satisfy all requirements, Admiral Nimitz also determined to seize for a fleet base Ulithi Atoll, 400 miles northeast of the Palaus. The invasion of the southern Palaus would begin simultaneously with the Southwest Pacific’s landing on Morotai, 15 September, while the seizure of Yap and Ulithi would start on 5 October. On 7 July Admiral Nimitz ordered his subordinate commanders to begin preparations accordingly.9

Thus, by late July, General MacArthur and Admiral Nimitz had set and agreed upon the sequence of operations in the Southwest and Central Pacific Areas for the last stages of the approach to the Philippines:–10

Morotai and the southern Palaus 15 September
Yap Island and Ulithi Atoll 5 October
The Talaud Islands 15 October
Mindanao (at Sarangani Bay) 15 November

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Strategic Air Support

With the dates for the final stages of the drive to the Philippines firmly established, planners of the Southwest and Central Pacific Areas turned their attention to the provision and coordination of strategic air support missions during the Palau and Morotai operations. The planners kept in mind that the major objective of the two operations was very broad in scope—to secure control over the eastern approaches to the Luzon–Formosa–China coast area. Strategic air support had to be planned with this task in mind, as well as the more obvious tasks of securing bases from which future operations could be supported and preventing enemy interference with the occupation of the Palaus and Morotai.11

It was not expected that the Japanese could or would retain any significant number of aircraft in the Palaus or the rest of the Carolines during the weeks immediately preceding 15 September; what few aircraft might remain on those islands could easily be destroyed or driven away by land- or carrier-based planes prior to that date. Much the same situation would prevail, it was believed at General MacArthur’s headquarters, in the Morotai area. The Allied Air Forces was expected to be able to neutralize remaining enemy airfields in western New Guinea, Ambon, Ceram, the Arafura Sea islands, and to a lesser extent in the northwestern Celebes, before 15 September. The remaining Japanese air power would probably withdraw from those targets to the southern Celebes or to the Philippines.12

The Japanese could be expected to organize some aerial counterattack to the Allied invasions of the Palaus and Morotai, since the fall of those islands would signify the loss of the last strategic defensive positions in front of the Philippines. The Japanese maintained large air centers in the southern Celebes and Mindanao from which they could send strong counterattacks against Allied forces at Morotai unless these fields were neutralized before 15 September. Less concern was felt about the possibility of aerial counterattack against the Palaus, since the Japanese were not believed capable of employing effectively many long-range bombers across the 600 miles of ocean which separated the Palaus from the principal enemy air centers on Mindanao. No aerial attacks of any significance could be launched by the Japanese against the Palaus from any other direction.13

A program for strategic air support missions to be executed by land-based aircraft was soon agreed upon by General MacArthur’s and Admiral Nimitz’ planners. Shore-based planes of the Central Pacific were to neutralize Japanese fields at Yap, Woleai, Truk, and Ponape in the Carolines; to prevent the Japanese from using airfields on islands of the Gilbert and Marshall

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groups not yet occupied by Allied forces; to hit the Bonin Islands and Marcus Islands, north and northeast of the Marianas, respectively; and to destroy enemy installations on Pagan Island, in the northern Marianas. Central Pacific land-based aircraft were also to fly reconnaissance missions in front of carrier task forces and assault convoys moving toward the Palaus.14

The Allied Air Forces was to reinforce strikes flown against Yap, Woleai, and Truk by Central Pacific land-based planes; execute heavy bombing attacks against the Palaus; and provide Admiral Nimitz’ planners with photographic coverage of these islands. The approach of Central Pacific carrier forces and assault convoys to the Palaus would be covered by Southwest Pacific planes flying strikes against southern Mindanao and Halmahera, and by long-range reconnaissance over the Celebes Sea, the Banda Sea, and the western reaches of the Philippine Sea.15 Within the limits of the Southwest Pacific Area, the Allied Air Forces was to continue the neutralization of Japanese air centers in western Dutch New Guinea, Halmahera, the Talaud Islands, Ceram, Ambon, Boeroe, and the Arafura Sea islands. Heavy strikes against targets in the Celebes were also to be undertaken in order to neutralize Japanese air bases there insofar as range permitted the Allied Air Forces’ land-based planes to do so.16

Missions assigned fast carrier task forces of the U.S. Pacific Fleet were even more widespread, geographically speaking, than those allotted land-based planes, and they entailed strikes on enemy installations which available land-based aircraft could not reach. Moreover, the carriers’ tasks included strikes of a type not previously executed—sustained attacks on ground targets where Japanese land-based air power was deployed in depth and was easily reinforceable, namely the Mindanao area. Such carrier operations had previously been considered unacceptable risks except in case of dire necessity, but Admiral Nimitz proposed to send his carriers on what he still believed to be a hazardous undertaking because he hoped the attacks on the Philippines might precipitate another fleet action. Moreover, he felt that the Philippine strikes would result in widespread damage to Japanese air power, thereby creating an opportunity for the Allies to secure control over the approaches to the Luzon–Formosa–China coast area earlier than might otherwise be possible.17

Strategic air support missions by the Pacific Fleet’s fast carriers were to begin with a strike against the Bonin and Volcano Islands, between the Marianas and Japan, late in August. This strike had a twofold objective: the temporary neutralization of Japanese airfields on those island groups and, more important, the creation of a diversion on the north preceding stronger attacks against targets in the Philippines and western Carolines. Carrier action in the latter area was to begin on 6 September, with strikes on the Palaus, Yap, and Ulithi. The

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bulk of the carrier forces was to leave the western Carolines on the afternoon of the 8th to take up positions off Mindanao.18

Japanese airfields on Mindanao presented difficult targets because they were scattered over that large island, but it was believed that the cluster of airfields and associated installations in the Davao area would provide profitable targets for carrier-based aircraft attacks. The Davao and Sarangani Bay areas, as well as Japanese shipping routes from Davao to Zamboanga and thence north toward Manila, were also expected to provide profitable targets. Strikes against airdromes and shipping in the Mindanao area were to be carried out on 9 and 10 September, while on the 10th and 11th part of the carrier force was to hit the Palaus and Yap–Ulithi again.19

At first, plans for carrier strikes called for raids on the Talauds, Halmahera, and Morotai from 12 through 14 September, but Allied Air Forces, Southwest Pacific Area, was confident its planes could neutralize the Halmaheras and Talauds, and General MacArthur, hoping to preserve chances for local tactical surprise, wanted no strikes against Morotai prior to 15 September. These tentative attacks were therefore canceled in favor of additional strikes in the Mindanao area.20 On D Day, 15 September, one group of fast carriers was to hit Japanese air bases at the northeastern Celebes early in the morning. Thereafter, this group was to stand by to provide close air support at Morotai if necessary, strike Japanese airfields on Halmahera upon General MacArthur’s request, and carry out general reconnaissance and covering missions in the Celebes Sea region. At the Palaus one group of fast carriers, which would have completed additional strikes against that island chain from 12 through 14 September, was to be available for close air support on D Day. The rest of the fast carriers were to stand by in position between the Palaus and Mindanao ready to execute whatever close or distant support missions proved necessary. Close air support at Morotai and the Palaus was primarily the responsibility of escort carrier groups.21

Final plans for land- and carrier-based strategic air support of the Palau and Morotai operations were completed by 20 August. The finished program provided for the most widespread and thoroughly integrated series of strategic air support missions yet undertaken within the Pacific theaters.

The Objectives

The Terrain

Morotai Island is not unlike Noemfoor except that everything at Morotai is on a larger scale.22 The roughly oval-shaped island

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is about forty miles long north to south and some twenty-five miles wide. The coast line, like that of Noemfoor, has many indentations and all types of beaches, including many that are reef-bound. Inland, most of the island is very rough and has peaks rising to 3,500 feet or more. The interior is covered with thick rain forest. The largest of the few lowland areas, called the Doorbell Plain, is located at the southwest corner.

Morotai had come under Portuguese rule in the late 16th century but passed to the Dutch early in the next. The Dutch controlled the 9,000 natives indirectly through the Sultanate of Ternate, Halmahera. Most of the natives lived along the east, south, and west coasts, leaving the interior virtually uninhabited. There was no commercial development before the war and the only white residents were a Dutch missionary and his family. The Japanese took over control in early 1942.

The Doroeba Plain, the only area where military development is practicable, is about nine miles wide, east to west, and extends inland about four miles. From the southwest corner of the plain the Gila Peninsula extends into Morotai Strait, which separates Morotai from Halmahera. The peninsula is about five miles long from the mainland to Cape Dehegila, at its southern tip, and has a maximum width of one mile. On the east side of the peninsula lies Pitoe Bay, the sea approaches to which are generally free of obstacles. The bay is deep and exposed to the weather, leaving much to be desired as a site for landings. Beaches on the west side of the peninsula are better protected and, although reef-bound, appeared prior to the landing to be better than those on the Pitoe Bay side. The western beaches provided easy access to the Doroeba Plain, where, it was believed, airdromes could be developed without undue difficulty.

The Palaus were more civilized than Morotai and some commercial development had been undertaken in the islands ever since they were occupied by the Spanish early in the 17th century.23 Spain sold the group along with the rest of the Carolines to Germany after the Spanish-American war. The Germans lost the chain to the Japanese during World War I, and Japan held the islands under League of Nations Mandate from 1920 to 1935, when she quit the League and began exercising de facto sovereignty over the islands. In the Palaus the Japanese undertook intensive development of bauxite and phosphate deposits. Colonization was promoted until by 1941 there were about 16,000 Japanese in the islands as opposed to some 6,250 natives of Micronesian stock. Over half the natives lived on the largest island, Babelthuap, while most of the Japanese were located on the smaller islands to the south, such as Peleliu and Koror. Koror Town, on the island of the same name, was the site of Japanese administrative and military headquarters. (Map 19)

All the islands of the Palau group are very irregularly shaped and most of them are quite hilly. The northern islands are of volcanic basalt, while those on the south

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Map 19: Palau Islands

Map 19: Palau Islands

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consist principally of coral and limestone. Peleliu, the most southerly island enclosed within the reefs surrounding most of the Palau group, is about five and three-fourths miles long northeast to southwest and a little over two miles wide. On the west, an arm some 3,500 yards long and 1,000 wide extends northeast from the main portion, and on the east a short peninsula and reef-connected islets form another arm. Between the two arms are shoals and swamps. A Japanese airfield was located in the southwest section of Peleliu.

The western side of Peleliu bears strong similarity to the southeastern section of Biak Island. Beginning just north of the airfield and running northeast up the western arm is a rough, broken, and densely forested ridge line like that running along the south shore of Biak. Equally broken, the Peleliu ridges presented much the same problems as those on Biak and provided the Japanese with similar defensive advantages. Landings on Peleliu are feasible at many points, but from the point of view of terrain and proximity to the airfield the best beaches are on the southwest coast.

Angaur Island, lying about ten miles south of Peleliu and outside the Palau reefs, is shaped like a very broad crescent, with its tips pointing northwest and southwest. The island is two and a quarter miles long north to south and about one and a half miles wide east to west. Flatter than Peleliu, Angaur’s highest point—about 200 feet—lies in wooded coral ridges at the northwest corner, where the terrain was as broken and as easily defensible as that in the Ibdi Pocket on Biak. The Japanese had extensively strip-mined phosphate deposits on Angaur, and water-filled diggings in the north-central and northwestern sections formed two small lakes. Narrow-gauge railroad tracks, running through dense underbrush in many places, connected the various mine sites.

Angaur has many reasonably good landing beaches, including some that are reef-free. Existing reefs are generally narrow and drop steeply off into deep water. There was a pier for small craft at a protected cove on the west-central coast, and about 400 yards to the north was a conveyor belt pier extending into the sea with its outer end attached to buoys. From this apparatus large cargo vessels were loaded with the product of the phosphate diggings. No protected anchorages exist off any part of Angaur. The best beaches are on the southwestern and northeastern coasts. Ngesebus Island, lying off the northern tip of Peleliu, is flat, sandy, and reef-bound. Site of a Japanese airfield, the island had no defensive potentialities except for a short, very low ridge along the western shore.

The Japanese

The Palaus and the Halmahera area were closely related in Japanese defense plans at one time or another during the war. Halmahera fell within the 2nd Area Army’s zone of responsibility. To defend that island and western New Guinea Imperial General Headquarters once laid plans to send the 32nd and 14th Divisions to the 2nd Area Army, while dispatching the 35th Division to the Palaus. As a result of various changes in plans, previously recounted,24 the 32nd Division and two regiments of the 35th Division (less elements sunk in transit) landed in Halmahera early in May 1944. One regiment of the 35th Division was first sent to the Palaus, where it arrived in April. Since

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the Japanese desired to have more strength in the latter islands, the 14th Division was dispatched there in April. The 35th Division’s regiment then sailed south to rejoin its parent unit, then on the move to Sorong and Manokwari from Halmahera, where the 32nd Division remained.25

Lt. Gen. Sadae Inoue, the 14th Division commander, was also appointed Commander, Palau Sector Group, in which capacity his area of responsibility included Yap and Ulithi as well as the Palaus. He was ordered by Imperial General Headquarters to hold the Palaus at all costs, to protect the airfields there and deny their use to the Allies. The main air base—that on Peleliu—had existed before the war, and had undoubtedly been employed by the Japanese for scouting and reconnaissance missions at the outbreak of war. The Palaus had also been used as a base by a small carrier task force which executed the first Japanese air raids against the Philippines in 1941, and later they were used as a staging base for units moving to Luzon, Mindanao, and the Netherlands East Indies.26 Afterwards, the Japanese had used the islands as an intermediate staging base and supply point for troops moving eastward to the 8th Area Army’s zone. Upon the withdrawal of the Japanese strategic main line of resistance westward in the spring of 1944, base troops in the Palaus, under Maj. Gen. Takeo Yamaguchi, passed to the control of the 2nd Area Army, and, when General Inoue assumed command of the Palau Sector Group, to the latter’s control.27

The Halmahera–Morotai area had not assumed much importance to the Japanese until early 1944, when they began to develop Halmahera as a focal point for the defense of the southern approaches to the Philippines. In addition to the 32nd Division, the Japanese had on Halmahera innumerable service organizations, and they completed or had under construction nine airfields on the island, most of them in northern Halmahera. On that island they concentrated nearly 30,000 men, including at least 11,000 combat troops. Morotai was neglected except for some work at Doroeba Plain. There the Japanese started an airstrip which they soon abandoned, apparently because of drainage problems.28

On Morotai the Japanese had stationed about 500 men of the 2nd Raiding Unit, which was commanded by Maj. Takenobu Kawashima. The officers were Japanese but most of the enlisted men were Formosans, and the unit was divided into four companies, the dispositions of which on 15 September are unknown. The Japanese had some grandiose schemes for counterattack from Halmahera in case Allied forces landed on Morotai, but by 15 September Morotai was isolated and there was no chance to reinforce it. Allied air power had destroyed Japanese air strength on Halmahera, brought to a stop ship movements to and from that island, and, after D Day, with the aid of PT boats, should be able to prevent barge traffic between Halmahera and Morotai.

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The Japanese made no attempts to reinforce Morotai in the weeks immediately preceding 15 September and, possibly in the vain hope that the Allies might make a landing in northern Halmahera—an eventuality for which the Japanese were well prepared—apparently forgot Morotai.29

Not so in the southern Palaus, on which General Inoue had prepared elaborate defenses, nominally in co-operation with Japanese Navy units in the islands.30 General Inoue planned to stop invaders at the beaches, but, in case of defeat at the shore line, his forces were to fall back on previously prepared positions inland. To aid beach defense, many offshore obstacles were constructed and many mines were laid. Inland, there were more mines. Antitank obstacles were constructed ashore, and weapons as well as defensive positions were concealed. Artillery pieces were well emplaced to oppose landings, and excellent use was made of natural terrain features for defense. The ridge lines of northwest Angaur and western Peleliu were honeycombed with defensive works on an even greater scale than those on the similar terrain of southern Biak.

By mid-May the Palau Sector Group had already taken up many defensive positions. Headquarters, 14th Division (also Group headquarters) was at Koror; the division’s 2nd Infantry was on Peleliu; the reinforced 59th Infantry, less one battalion, was on Angaur; and the 15th Infantry, with the other battalion of the 59th attached, was on Babelthuap and the remaining islands. Many supporting weapons were already emplaced, and other gun positions were rapidly nearing completion. Both Angaur and Peleliu were divided into four defensive sectors and each maintained a central reserve.

Babelthuap and the central islands were placed under the command of General Yamaguchi who, in addition to the various 14th Division units disposed in his area, also had under his command the Sea Transport Units (probably landing craft and crews) of the 1st Amphibious Brigade and the various staging base troops previously attached to the 2nd Area Army. On 30 May these latter troops were reorganized into the 53rd Independent Mixed Brigade (IMB), over which General Yamaguchi retained command. One of the 53rd IMBs six infantry battalions was sent to Peleliu to reinforce the 2nd Infantry, as was the 3rd Battalion, 15th Infantry. The Peleliu garrison also included artillery, mortar, and signal units, and a tank organization containing twelve light tanks. The garrison totaled about 10,500 men, of whom almost 6,300 were combat troops. The Peleliu Sector Unit, as the Peleliu garrison was designated, was commanded by Col. Kunio Nakagawa, also the commander of the 2nd Infantry.31

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Late in July, for unknown reasons, General Inoue withdrew the bulk of the 59th Infantry to Babelthuap, leaving only the reinforced 1st Battalion of that regiment on Angaur. This battalion, commanded by Maj. Ushio Goto, was the nucleus of the Angaur Sector Unit (also under Major Goto), and had attached to it a few heavy artillery pieces, a battery of mountain artillery, some antiaircraft and antitank guns, a heavy mortar platoon, an engineer platoon, and miscellaneous service troops. The garrison totaled about 1,400 men.

Until August the Palau Sector Group was attached to the 31st Army (command post on Saipan), in turn under the operational control of the Central Pacific Fleet. But after the fall of the Marianas Imperial General Headquarters reassigned the Group administratively to the Southern Army and operationally to Headquarters, Combined Fleet. On 3 September Southern Army informed General Inoue that an Allied invasion of the Palaus was imminent. But the general apparently took this news with at least one grain of salt, for on the 8th he interpreted Allied carrier strikes on the Palaus as a diversion intended to cover landings elsewhere. It was not until the 11th that he changed his mind and alerted his command to make final preparations to defend the islands to the death.

And by 11 September about all the Palau Sector Group could look forward to was death or surrender. Sometime during the summer of 1944, probably not long after the Allied invasion of the Marianas and the concomitant naval battle, the Japanese had come to the conclusion that the Allies might not land in the Palaus and that seizure of those islands was not a necessary prerequisite to an Allied advance to the Philippines. But shipping could not be risked to take the Palau Sector Group away from the islands, and, moreover, should the Allies finally decide to take the Palaus, even a hopeless defense might delay Allied use of the Palau air bases. On the other hand, the Japanese were concentrating all their efforts on preparing the defense of the Philippines; they could spare no planes, ships, or troops to strengthen islands which they thought the Allies might bypass.

Therefore, after July 1944, only the barest trickle of the most necessary supplies was shipped to the Palaus. And even this trickle diminished toward September, for increasingly effective Allied air and submarine operations in the western Pacific did not encourage the Japanese to dispatch so much as a landing barge to the Palaus. The Palau Sector Group was a hopeless case indeed. It could look forward on the one hand only to death or surrender in case of an Allied landing, or on the other hand to being bypassed and left behind, useless, like garrisons in New Guinea and the Bismarck Archipelago that had been isolated earlier in the war.

Accurate information concerning enemy defenses in the Palaus was not available to the Allies until many highly classied documents from the files of Headquarters, 31st Army, were captured in the Marianas during July.32 One such document in particular, dated 8 June 1944, gave detailed supply data for Japanese forces in the Palaus and provided the initial basis for Allied estimates of the enemy situation in the islands as well as for much of the tactical planning.

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In mid-August new information permitted remarkably accurate revisions in the Allied June estimates. By that time, however, the principal Allied units concerned with operations in the Palaus had completed and issued their final tactical plans. The revisions were too late or lacked sufficient corroboration to materially change these approved plans.

Organization, Tactics, and Logistics

The Organization and Missions of the Forces

The organization of Southwest Pacific Area forces for the Morotai operation differed little from that for previous operations in the theater. As usual, ALAMO Force was responsible for the seizure and development of the objective area, with the support of the Allied Air and Allied Naval Forces. The Morotai plan called for the occupation of a perimeter about fifteen miles long around airfields to be constructed in the southwest section of the island. To hold this perimeter, to establish and protect radar stations around the island’s shores, to seize a beachhead against a possible regiment of Japanese (which, it was estimated, could be on Morotai), and to defend against whatever counterattacks the Japanese might strain themselves to mount from Halmahera, General MacArthur considered that no less than a reinforced division plus another regimental combat team would be needed.33

For this operation General Krueger chose the 31st Division (most of which was at Wakde–Sarmi except for one regimental combat team at Aitape) and the 126th Regimental Combat Team of the 32nd Division (at Aitape). Headquarters, XI Corps, under Maj. Gen. Charles P. Hall, was chosen to coordinate the operations of the 31st Division, the 126th Regimental Combat Team, and various attached combat and service units. As Headquarters, PERSECUTION Task Force, General Hall’s command had been in action at Aitape from late June to late August. For Morotai, his corps was designated the TRADEWIND Task Force. The 31st Division, under Maj. Gen. John C. Persons, was to execute the initial landings as the TRADEWIND Assault Force. The 126th Regimental Combat Team was named TRADEWIND Task Force Reserve. ALAMO Force Reserve for the operation was the 6th Infantry Division (less one regimental combat team) at Sansapor.34

Other major combat units of the TRADEWIND Task Force were an antiaircraft group of 3 automatic weapons battalions, 2 gun battalions, and 1 searchlight battalion; a medium tank company; a 4.2-inch mortar company; a signal battalion, less 2 companies; a military police company; the 534th Engineer Boat and Shore Regiment, less the Boat Battalion; and the 544th Engineer Boat and Shore Regiment, less 1 boat company. These combat components (including the reinforced 31st Division and the 126th Regimental Combat Team) numbered almost 28,000 men. The bulk of the service units assigned to the task force were engineer organizations destined to construct airfields and related installations. Service troops totaled about 40,200 men.35

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Naval organization was headed by Rear Adm. Daniel E. Barbey of the VII Amphibious Force as Commander, Task Force 77, the Attack Force. His amphibious command was divided into two groups totaling 12 destroyers, 2 APAs, 5 APDs, 1 LSD, 39 LCIs, 12 LSTs, and 12 LCTs. Also under Admiral Barbey was a Close Support and Covering Force, commanded by Rear Adm. Russell S. Berkey and containing 2 heavy cruisers, 3 light cruisers, and 10 destroyers. Close air support was to be provided by Rear Adm. Thomas L. Sprague’s Task Force 78—6 CVEs and 10 DEs.36 One fast carrier group of 2 CVs, 2 CVLs, 3 heavy cruisers, and 12 destroyers—Task Group 38.1—under Vice Adm. John S. McCain, was to provide additional air support as needed. This group was not under Admiral Barbey’s control, but was to operate with his Attack Force by co-operation.37

The Allied Air Forces, charged with the conduct of land-based air support for Morotai, designated the U.S. Fifth Air Force as the assault air force for that operation. This unit was not to conduct strikes on Morotai before D Day but was to hit near-by Japanese installations on that day and during the weeks preceding the landings. In addition, the Fifth Air Force was to aid the CVEs in protecting convoys moving toward Morotai and was to be ready to fly such close support missions over that island as might be necessary on and after D Day. The other echelons of the Allied Air Forces—the Thirteenth Air Force, the Royal Australian Air Force Command, and land-based planes of the Allied Naval Forces—had no close support missions but were assigned many strategic missions. The air garrison at Morotai was to be provided by the Thirteenth Air Force and included an advanced echelon of that unit’s headquarters.38

The organization of Central Pacific units for the move to the Palaus centered on Admiral William F. Halsey as the Commander, Western Pacific Task Forces, or, administratively speaking, the Commander, U.S. Third Fleet.39 Admiral Halsey’s missions were as follows: to occupy the Ulithi–Palaus line; to destroy or contain Japanese naval and air forces threatening interference with such occupation; to protect sea and air communications through the forward areas of the Central Pacific; and to provide air cover for the Morotai operation in the Southwest Pacific Area.

Admiral Halsey divided his Western Pacific Task Forces into two major combat echelons. The first of these was the Covering Forces and Special Groups (Task Force 30), over which Admiral Halsey retained direct command. The other section was designated the Joint Expeditionary Force and was placed under Rear Adm. Theodore S. Wilkinson, who was also the commander of the Third Fleet’s III Amphibious Force (Task Force 31).

The principal combat component of the Covering Forces and Special Groups was

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Chart 14: Organization for 
the Palau Operation

Chart 14: Organization for the Palau Operation

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Vice Adm. Marc A. Mitscher’s Fast Carrier Task Force, Task Force 38. Admiral Mitscher was responsible for conducting strategic air support missions, for hitting enemy naval forces threatening landing operations in the western Carolines, and for providing close air support for the Morotai and Palau landings. Also included within the Covering Forces and Special Groups was a Heavy Surface Striking Force of battleships, cruisers, and destroyers which, in case of fleet action, would be formed by ships otherwise assigned to Task Force 38’s four fast carrier groups. A Light Surface Striking Force of light cruisers and destroyers was to be formed from fire support ships otherwise assigned to Admiral Wilkinson’s Joint Expeditionary Force. In case of fleet action, this latter striking force would be transferred to the Covering Forces and Special Groups. The Special Groups comprised a flagship group, a service group of repair ships, an oiler and transport group, and a hunter-killer group of 1 CVE and 4 DEs organized to hunt down Japanese submarines. In addition to the specific missions assigned its component parts, the Covering Forces and Special Groups had the general task of utilizing all possible opportunities which might be presented or created to destroy major portions of the Japanese fleet.

Under Admiral Wilkinson’s Joint Expeditionary Force were the Western and Eastern Attack Forces, assigned the task of securing the southern Palaus and Yap–Ulithi, respectively. Other components of Admiral Wilkinson’s command were a Fire Support Group, an Escort Carrier Group, and a Minesweeping Group. The Western Attack Force, commanded by Rear Adm. George H. Fort, had three parts—the Peleliu and Angaur Attack Groups and the Kossol Passage Detachment. Admiral Fort retained command over the Peleliu Attack Group and delegated the control of the Angaur Attack Group to Rear Adm. William H. P. Blandy.

Maj. Gen. Julian C. Smith (USMC), as Commander, Expeditionary Troops, was to be in control of all ground action in the western Carolines. His position was roughly analogous to that of General Krueger of ALAMO Force in the Southwest Pacific, and was equivalent to that of an Army commander. The ground force commander for the southern Palaus was Maj. Gen. Roy S. Geiger (USMC), who commanded the Western Landing Force and Troops, or, as his headquarters was otherwise known, the III Amphibious Corps.40 The principal ground combat elements assigned to the III Amphibious Corps were the 1st Marine Division, under Maj. Gen. William H. Rupertus (USMC), and the 81st Infantry Division, commanded by Maj. Gen. Paul J. Mueller. The former was to seize Peleliu and the latter, less one regimental combat team in corps reserve, was to take Angaur. In general reserve for operations in the western Carolines were the 5th Marine and 77th Infantry Divisions. The 1st Marine Division had seen action on Guadalcanal in the South Pacific and on New Britain in the Southwest Pacific. Some 30 percent of the unit’s men had been in both operations and 60 percent had been in one or the other. The 81st Infantry Division had no previous combat experience and, when assigned to the Palau operation, was finishing jungle and amphibious training in Hawaii. The 77th Infantry

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Maj

Maj. Gen. Paul J. Mueller (left), with Rear Adm. Robert B. Carney (center) and Admiral William F. Halsey (right)

Division had seen action on Guam in the Marianas, while the 5th Marine Division was without combat experience.

Once all objectives in the western Carolines had been secured, responsibility for their defense and development would pass to the Forward Area Central Pacific (Task Force 57), commanded by Vice Adm. John H. Hoover. The latter delegated his duties in the Palaus to Rear Adm. John W. Reeves as the Commander, Western Carolines Defense and Service Forces (Task Group 57.14).

The Palau Tactical Plan

The production of all plans concerned with the seizure and development of the Palaus was complicated by many changes in objectives within the island group and by many other changes in headquarters, commanders, and units assigned to the operation.41 Plans started with the concept of

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securing the entire Palau group, passed through many changes to a concept of seizing only the southern Palaus, with Angaur first and Peleliu second, and, ultimately, called for the seizure of Peleliu first and Angaur within a day or two thereafter. Although study of operations in the Palaus had been under way in various headquarters in the Pacific Ocean Areas since early 1944, it was not until late May that Admiral Halsey was made responsible for the planning and execution of those operations. On 1 August he issued an outline plan for the invasion of the western Carolines and left detailed tactical planning to subordinate agencies.

Admiral Wilkinson’s Joint Expeditionary Force headquarters started its planning in May, while the staff of III Amphibious Corps, located at Guadalcanal, started work on its planning late the same month. About mid-June the III Amphibious Corps headquarters learned it would probably not be released from missions in the Marianas in time to participate in the Palau operations. Therefore, a provisional corps headquarters was set up at Pearl Harbor to finish the planning and to carry out the operation. But the III Amphibious Corps was through in the Marianas earlier than was expected and was reassigned to the Palau operation on 15 August. Most of the men of the provisional corps headquarters thereupon formed the nucleus for the staff of General Smith’s Headquarters, Expeditionary Troops. Final plans of both headquarters were revised as necessary and were completed within a few days.

The 1st Marine Division began its planning at its camp in the South Pacific early in June, but it was not until the second week in August that members of Admiral Fort’s Western Attack Force staff could reach Guadalcanal for essential joint planning. The division’s landing plans were therefore not completed until late August. The 81st Infantry Division started its planning in Hawaii during early July, making many changes as the concept of the operation was changed. Two regimental combat teams were finally assigned to the invasion of Angaur upon their release from a feinting and reserve role during the assault on Peleliu. The remaining regiment, initially in reserve for the 1st Marine Division, became III Amphibious Corps Reserve late in August. At the same time, the 81st Division was relieved of an earlier assignment to commit one combat team to Yap or Ulithi. This last revision made it necessary for the division to make provision to unload the entire unit on tiny Angaur. A final change was made on 16 September, when one regimental combat team, assigned to corps reserve, was redesignated the assault force for Ulithi. Despite such troubles, and many others for which lack of space

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prohibits detailed description, most of the units assigned to the Palau operation had their plans completed by mid-August, and final details were settled before the end of the month.

The 1st Marine Division was to begin landings on Peleliu at 0830, 15 September, with five battalions abreast over WHITE Beaches 1 and 2 and ORANGE Beaches 1 through 3 on the southwest shore of Peleliu, opposite the Peleliu airfield. (Map VI) The assault waves were to be carried ashore in LVTs and LVT(A)s. The 1st Marines was to land on the left (north) to drive up the western shore and clear the Japanese from the ridges overlooking the airfield. The 5th Marines was to land in the center, securing the airfield and dividing the island, while the 7th Marines was to seize the southern end of the island. The 11th Marines (artillery), reinforced by two 155-mm. battalions of III Amphibious Corps artillery, was to start moving ashore at H plus 60 minutes. One 155-mm. battalion was to find positions whence it could provide support for the 81st Division’s landing on Angaur.

Two beaches were selected for the landings of the 81st Infantry Division at Angaur on F Day, as the day for landing on that island was designated. (Map VII) RED Beach, located on the northeast coast, was about 250 yards wide and was flanked on its left by a small promontory and on its right by rough shore at the northern tip of the island. About 200 feet off the center of this beach was located a tiny rocky islet. The 322nd Regimental Combat Team was to land on RED Beach at 0830 with two infantry battalions abreast, each carried ashore in LVTs. There was some discussion of whether to commit the assault battalions abreast or in column over narrow RED Beach, but it was decided that the landing abreast would have the advantage of bringing each battalion’s heavy weapons into action sooner than might otherwise be possible and would prevent confusion that might result from one battalion’s passing through the lines of another on its way forward. The remaining battalion of the 322nd Infantry was to move ashore on LCVPs or, alternatively, on LVTs to which they would transfer in the stream from the LCVPs.

BLUE Beach, where the 321st Regimental Combat Team was to land, was located southeast of RED Beach and on the east central shore of Angaur. The two were separated by nearly 2,000 yards of rough coast line and eastern capes of the island. It was realized that such widely separated landings were not particularly desirable, but the choice of beaches was dictated by the nature of the Angaur terrain and known or suspected Japanese defensive dispositions. Aerial photography had indicated that an excellent beach near the northwest tip of Angaur was backed by terrain which would make progress inland extremely difficult; beaches on the southwestern and southeastern shores of the island, although wider and backed by more favorable terrain than RED and BLUE Beaches, were more strongly defended and more distant from important objectives, including the northwest hill mass, which was expected to be the center of Japanese resistance. Finally, the chosen beaches had no wide barrier reefs in front of them.

Division reserve for the landing was the 3rd Battalion, 321st Infantry, which was to land on either beach on call. The III Amphibious Corps Reserve (the 323rd Regimental Combat Team) was to make a feint at a beach not used by the rest of the division in order to keep the enemy defenders confused

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as to the location of the principal landings. It was hoped that this feint would also immobilize any enemy reserve.

Once ashore, the two assault regiments were to drive directly inland to secure a first phase line, which was drawn approximately 300 yards from the beaches. Not until the first phase line had been secured in each regiment’s sector were flank units to make contact between the two assault forces. Elements of each regiment were then to sweep back toward the beaches and the northeast cape to secure the terrain which had been bypassed on the way inland. The boundary between regiments began at the east capes (about midway between the two landing beaches) and ran west-southwest about 2,200 yards across the island to a junction of many of the island’s narrow-gauge railroad lines at a point about 1,000 yards inland from the west-central coast. Thence the boundary went south-southwest until it hit the southwest beach of the island at Garangaoi Cove, about 600 yards above the island’s southern tip.

The boundary line was arbitrarily drawn without reference to existing features, such as some of the narrow-gauge railroads. One of the principal reasons for selecting such a line was to place Cape Ngatpokul, one of the east capes, in the 322nd Infantry’s zone of action. Cape Ngatpokul projected toward RED Beach, and from it the enemy might pour down enfilade fire on the 322d’s landing operations. One battalion of the regiment was to swing sharply left upon landing to secure the cape, while the 321st Infantry was made responsible for securing Cape Ngariois, the more southern of the east capes. The 322nd Infantry was also to secure Cape Pkul A Mlagalp, at the north tip of the island; the hill mass at the northwest corner of the island; and Saipan Town, which, lying on the west-central coast, was the principal Japanese settlement on the island and the only population center of any note. The 321st Infantry was to secure the entire southern section of the island, excluding Saipan town.

The 81st Infantry Division’s artillery was faced with a peculiar problem in providing support for ground action on Angaur, for the island was extremely narrow. If the 105-mm. battalions landed on the beach behind the infantry regiment each was to support, both would have to fire on targets less distant than minimum effective support ranges or from positions from which good angles of fall could not be obtained. But there were no near-by islands where the 105-mm.’s could land, and they could not safely land on Angaur except at the beaches the infantry was to secure. Therefore, the 105-mm. battalion which was to support the 321st Infantry was to land on the 322nd Infantry’s beachhead, and the latter’s artillery was to land behind the 321st Infantry. Each 105-mm. battalion would fire diagonally across the front into the zone of the regiment it was to support, thereby gaining sufficient range and trajectory clearance for effective close support and reducing the danger of range deviations.

Two of the division’s 105-mm. battalions were to land on call at the beaches, while the third remained afloat as part of the 323rd Regimental Combat Team unless it was needed on Angaur. The division’s 155-mm. battalion was to land on Angaur on F plus 1 day. To provide some heavy support until the two 105-mm. battalions could get ashore, a battery of 4.2-inch mortars was to be landed on BLUE Beach with the leading waves.

It is well-nigh impossible to clearly distinguish between the strategic and close air

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support missions flown by carrier-based aircraft in the Palaus area. Fast carrier strikes were to begin on D minus 9, 6 September, and were to be preceded by attacks from the Southwest Pacific’s Fifth Air Force, which was to continue night attacks on the Palaus while the carriers were in the area. From D minus 9 through D minus 4, area targets were to be covered, while attacks on pinpointed targets were to begin on 12 September, in conjunction with naval gunfire support and mine-sweeping activities.

Fast carriers were also to provide some close air support on D Day at Peleliu and F Day at Angaur, in addition to the support to be obtained from CVE-based planes. No strikes against Angaur were scheduled for 15 September, but on F Day supporting aircraft were to hit known or suspected gun emplacements and defensive installations. There were also to be strafing attacks on the beaches. Because of the peculiar angle at which RED and BLUE Beaches lay in relation to each other, the strafing groups would fly a fine collision course if they executed their strafing perpendicular to the beaches, as was most desirable. Therefore, both groups were to head into the beaches almost due west, with the RED Beach group pulling up to the right and the BLUE Beach group pulling up to its left.

The original gunfire support plan for the Palaus called for two days of bombardment prior to D Day, but the III Amphibious Corps, concerned over the possibility of strong defenses near the. landing beaches, especially on Peleliu, asked for four days. Admiral Wilkinson could not entirely accede to this request since ammunition was lacking, but he did add one more day’s bombardment. This did not increase the actual weight of ammunition, but rather called for the expenditure of the same amount over a longer period of time and in a more deliberate fashion.

The Peleliu Fire Support Unit, comprising 4 old battleships, 3 heavy cruisers, 1 light cruiser, and 9 destroyers, was to start firing at 0530 on D minus 3. The destroyers and LCIs (rocket and gunboat) of the assault convoy were also scheduled to engage in fire support missions. The bombardment from D minus 3 through D minus 1 was to be divided between Peleliu and Angaur. On F Day the Angaur Fire Support Unit (2 old battleships, 1 heavy cruiser, 3 light cruisers, and 4 destroyers) was to start its work two hours before the landing. From H minus 30 minutes to H Hour the ships were to hit the beaches, gradually spreading their fires to the flanks and inland as the landing waves approached the shore; from H Hour to H plus 20 the fire was to be directed inland in front of the advancing infantry.

Four LCI mortar boats and two LCI gunboats were to support the landing on RED Beach, while seven LCI gunboats were to be in support at BLUE Beach. The LCI mortar boats were to begin firing about H minus 25 and were to stop when the leading boat waves were about 1,200 yards from shore, or H minus 8 minutes. The LCI gunboats were then to fire rocket salvos, after which they were to continue 20-mm. and 40-mm. fire on the beaches as the leading waves moved shoreward. Five of the gunboats were to devote special attention to the area between the two landing beaches.

Logistics of the Palau Operation

Approximately 49,500 troops were assigned to the III Amphibious Corps to execute the occupation and development of

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the Palaus during the assault phase of operations on those islands. These troops were divided between services as follows:–

U.S. Army 19,800
U.S. Marine Corps 24,300
U.S. Navy 4,800

Most of the naval personnel were either organic to or attached to the 1st Marine Division, although a few were attached to the 81st Infantry Division or Headquarters, III Amphibious Corps. The approximate breakdown among major tactical units was as follows:–

Headquarters, III Amphibious Corps 150
1st Marine Division, reinforced 28,400
81st Infantry Division, reinforced 21,100

About 63,800 tons of supplies and equipment were scheduled to be sent ashore for the III Amphibious Corps. Of this amount, the 81st Division was to unload about 29,500 tons of supplies, while the 1st Marine Division, some 7,000 men stronger, was to put ashore on Peleliu about 5,000 more tons of cargo. The ships assigned to move the 49,500 men and 63,800 tons of supplies to the Palaus were:–42

Type 1st Marine Division 81st Infantry Division Total
AP 1 3 4
APA 10 9 19
APH 2 0 2
AK 0 1 1
AKA 4 2 6
LST 30 21 51
LSD 2 2 4

The III Amphibious Corps’ assault units were to take with them to the Palaus 32 days’ supply of rations, 5 days’ supply of water, 20 days’ supply of clothing and unit equipment, 20 days’ supply of fuels and lubricants, 30 days’ supply of medical material, and 20 days’ supply of small boat and motor maintenance equipment. Five “CINCPOA” units of fire for all weapons were to be taken ashore during the assault phase. The 105-mm. howitzers were to be supplied with two additional units of fire, while 57-mm. antitank guns were to get four additional units.43

Such was the general supply plan as determined by Headquarters, Expeditionary Troops. The 1st Marine and 81st Infantry Divisions’ individual supply plans varied

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somewhat in detail, but in one way or another carried out the provisions of the general supply directive. The 81st Division was to put its supplies ashore in three phases—(1) in boats of the assault waves; (2) in floating reserve offshore in LSTs or in LVTs and DUKWs which unloaded the LSTs, to be called ashore when possible or necessary; and (3) on cargo ships such as APAs and AKAs, also lying offshore. The ships of the latter category were to be unloaded as soon as possible after the Angaur beaches had been secured.44

The 1st Marine Division’s supply plan called for placing ashore within a few days after the first landings all supplies as required by the general plan. Suspecting that the terrain on Peleliu might call for extensive use of weapons not usually employed in open land warfare, the division decided to take with it ten extra units of fire of flame thrower fillers and ten additional units of fire of explosives.45

To unload supplies at the far shore, the 1st Marine Division organized four separate shore party groups, one for each regimental combat team and one to act as division shore party headquarters. To man these four groups, six different units organic or attached to the division were divided sixteen different ways. The 81st Infantry Division assigned to each of its regimental combat teams for shore party work an engineer combat battalion. These three battalions were not split up, but operated as integral units under the general direction of an engineer group headquarters.46

The 81st Division, while loading, reported as its only critical shortage spare parts for LVTs. At first there was a shortage also in organizational equipment, the division having arrived in Hawaii with far less equipment than was needed for operations in the Palaus. Most organizational equipment shortages were made up prior to embarkation, though at the last possible moment.47 Early shortages of the 1st Marine Division included amphibian tanks, tank spare parts, signal equipment, bazookas, BARs, pack-type flame throwers, and submachine guns. By the time the division’s ships were loaded all these shortages had been made up, although some equipment arrived so late that it could not be properly loaded and had to be crammed aboard transports in the most expeditious method available.48

Initial engineer missions, in addition to shore party activities, were those common to all amphibious operations—establishing beach roads, clearing dump areas, cutting roads inland from the beaches, destroying enemy defensive installations, and supporting infantry action with demolitions. Two U.S. Navy construction battalions (CBs) were to rehabilitate the field on Peleliu for the use of fighter aircraft, at least, as soon as possible after landing. This field was to be extended for bombers, and the Japanese fighter strip on Ngesebus Island was also to be repaired. On Angaur, where no airdrome had previously existed, two U.S. Army engineer aviation battalions were assigned the task of constructing, by F plus 30, an airfield and associated installations adequate

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for the operations of a heavy bomber (B-24) group.49

Rehearsals for the 81st Division began on 31 July at Maui Island, Hawaii.50 The first day was spent on debarkation drills, formation of boat waves, and transfer of troops from LCVPs to LVTs. The next day the 323rd Infantry (less one battalion, which could not participate because ships were lacking) made a practice landing, remaining ashore to act as an enemy force while the other two regiments made their practice landings on 2 and 3 August. By staggering landings, all assault elements were able to participate in reasonably complete rehearsals. However, only 25 percent of the supplies were unloaded and not all the division artillery could take part, since not enough DUKWs were available to provide all units with opportunity to practice unloading weapons from such vehicles.

Final rehearsals were undertaken in the Guadalcanal area beginning on 30 August. On that day the 321st and 322nd Infantry Regiments participated, but artillery and tanks were not landed. Another landing was carried out on 1 September by the same units, this time with some of the artillery participating and, for the first time, with actual naval gunfire and aerial support. A third exercise was executed on 3 September for the benefit of the 323rd Infantry. Throughout the Guadalcanal rehearsals, the number of vehicles unloaded was drastically limited, principally because waterproofing material had to be husbanded for the actual assault on Anguar.

The 1st Marine Division carried out its rehearsals in the Guadalcanal area, where training was complicated by lack of space; by the fact that the division was receiving 40 percent replacements; by the necessity for organizing new LVT(A) units; and, finally, by a shortage of some types of equipment. Artillery units had little time to practice loading and unloading their weapons into LVTs and DUKWs. Furthermore, the training area at Pavuvu Island had in common with Peleliu only a wide fringing reef, and the last rehearsal area, the Tassafaronga region of Guadalcanal, lacked even the reef.

The 81st Division’s loading, which took place in Hawaii, was complicated by a number of factors, notably the many changes in the concept of the Palau operation. The division’s tactical groupings were not definitely settled until two weeks before the unit left Hawaii for Guadalcanal; before that time only theoretical loading plans could be worked out. In the end, almost all troop loading tables had to be revised, largely on the basis of inquiry as to which units were actually loaded on each ship during a series of staggered staging dates. About 60 percent of the cargo was loaded from 26 through 28 July, after which the loaded vessels took part in the Maui rehearsals. Loading was completed after 5 August, and much cargo had to be readjusted in holds to conform with final tactical plans. It was impossible for the division to combat-load all its cargo, for many supplies were not received at the docks until the day the division left Hawaii. As a result, some low priority cargo was placed in holds

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above high priority matériel. But sufficient high priority cargo was available when needed.

Dispersion of units and supplies at Hawaii created other problems. Most of the supplies had to be gathered and palletized—the division pallet-loaded the bulk of its supplies—at a depot some six miles from loading piers. Some troops were bivouacked even farther away. Some confusion resulted because the division Transport Quartermaster, faced with many changes in tactical plans and groupings, had insufficient time to publish and distribute loading tables far enough in advance to permit subordinate units properly to prepare their own plans. General Mueller finally directed regimental commanders to assume the loading responsibilities for their regiments and attached combat team units. Final loading was greatly decentralized, and the G-4 Section did not have a complete picture of the situation. There were many last-minute improvisations, such as employing one AKA as a cargo overflow vessel and drawing up new storage charts as ships were loaded. By 12 August, however, the division was completely loaded except for some medical matériel, not immediately available, which was flown to Guadalcanal for last-minute stowing aboard ships.

The 1st Marine Division, like the 81st Division, was plagued by necessity to load and rehearse simultaneously and by the late arrival of many cargo ships at Guadalcanal. Detailed planning for loading was impossible until the last moment, and inevitably many compromises and improvisations had to be made. Loading operations were undertaken at five widely separated points in the Guadalcanal area, and many ships had to pick up parts of their cargoes at two or more places. Finally, shortage of lighterage and docking facilities at some loading areas complicated staging.

For large cargo vessels, no unusual loading methods were employed. Insofar as possible, all were combat-loaded and much cargo, especially rations, ammunition, and medical supplies, was palletized. For LSTs, loads averaged from 500–750 tons. Bulk cargo was placed along one side of the LST tank decks, care being taken not to block door entrances, and was so arranged that three rows of vehicles could be stowed on the tank decks. Some bulk cargo was placed under DUKWs; some was placed in bins in the after section of the tank decks; and none was stowed to a height of over four feet. All loading and cargo readjustment for amphibious craft was completed before 4 September, upon which date the Palaus assault convoys began leaving the Guadalcanal area.

The Tactical and Logistic Plan for Morotai

Since little opposition was expected at Morotai and since it was extremely important to develop airfields on that island rapidly, the landings there were to take place close to the prospective airfield sites on the Doroeba Plain of southwest Morotai. (Map 20). General Krueger originally wanted landings to be made on both sides of the Gila Peninsula, jutting south into Morotai Strait from Doroeba Plain, but Admiral Barbey was opposed to this plan. First, exposed waters and lack of good anchorages on the east side of the peninsula would make unloading difficult, and second, landings on both sides would interfere with naval gunfire support and endanger the troops pouring ashore. It was therefore decided that the first landings would be made on two

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Map 20: Morotai Landings, 
15 September 1944

Map 20: Morotai Landings, 15 September 1944

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beaches—WHITE Beach on the west side of the Gila Peninsula and RED Beach on the mainland coast above the west head of the peninsula.

The 124th Infantry, 31st Division, was to begin landing on WHITE Beach at 0830, 15 September, in column of battalions. One battalion was to swing south to secure the Gila Peninsula while the other two drove inland and northeast along the south coast of Morotai to secure a beachhead area about 1,000 yards deep. The 167th Infantry, 31st Division, was to land in column of battalions on the south half of RED Beach beginning at 0830. This beach, located some 1,500 yards north of WHITE Beach, was nearly opposite the seaward end of Pitoe Drome, as the abandoned Japanese airstrip on Morotai was designated. Two battalions were to drive inland to secure the drome while the other assembled in reserve. On the north (left) half of the beach the 155th Infantry, 31st Division, was to land in column of battalions to drive inland north of Pitoe Drome in conjunction with the advance of the 167th Infantry. The D Day objective line for both regiments was situated about 2,200 yards inland.51

Leading waves at RED Beach were to consist of LVTs, while the assault on WHITE Beach was to be made in LCPRs. These waves were to be supported by LCI rocket and gun boats, which were to move as close inshore as the fringing reef would permit. Plans for the landing of artillery, engineers, and other supporting arms and services were similar to those employed in previous operations in the Southwest Pacific. There was, however, one unusual feature concerning the employment of the 126th Regimental Combat Team, TRADEWIND Task Force Reserve. The 1st Battalion, 126th Infantry (less its heavy weapons company), was to go ashore on D Day at WHITE Beach expressly for the purpose of providing labor at the beachhead. The rest of the combat team was to reach Morotai on D plus 1.52

As usual, the Allied Naval Forces was to move the first troops and supplies of the TRADEWIND Task Force to Morotai. General Headquarters expected that the Services of Supply would relieve the Allied Naval forces of this responsibility on D plus 15. Allied Naval Force units were responsible for providing their own supplies, but in an emergency could draw from Services of Supply stocks. Most of the Allied Air Forces supplies were to be provided through air forces supply channels, but others were to be provided by the Services of Supply. At Morotai, Australian engineer units attached to the TRADEWIND Task Force were to be provided with rations and clothing by the task force upon request. Netherlands Indies Civil Administration units were to draw all their supplies in the forward area through the task force quartermaster.

The various ground elements of the task force were to draw their initial supplies from Services of Supply bases or ALAMO Force supply points at which each unit staged for the operation. ALAMO Force was responsible for resupply. Typical among the measures taken by ALAMO Force to carry out this responsibility was a provision to have one unit of fire for all weapons of assault units sent to Morotai on each of two troop-carrying ships on D plus 1. Another example was provision for sending forward

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twenty-five tons of rations on each LST scheduled to arrive at Morotai on D plus 1, D plus 2, and D plus 4. The Allied Air Forces was to be prepared to transport supplies by air to Morotai in an emergency.53

The assault echelons of the TRADEWIND Task Force (units reaching Morotai from D Day through D plus 4) were to be provided with 10 days’ supply of rations, clothing, unit equipment (except ordnance and engineer unit equipment), fuels, and lubricants. Ordnance equipment was limited to organizational sets of spare parts, while 30 days’ supply of engineer unit equipment was to be taken forward. Because of anticipated rain and dampness at the objective, all units were to take 30 days’ supply of cleaning and preserving materials for all weapons. Provision for engineer construction matériel was the same as that for previous operations. A schedule of shipment for such cargo was established to coincide with anticipated progress of construction at that island.

The assault units were provided with two units of fire for all weapons and five units of fire of fragmentation hand grenades. At Morotai, ammunition dumps were to be established to provide three units of fire for all weapons. After D plus 4, additional supplies were to be sent forward to furnish 30 days’ supply of rations, clothing and unit equipment, fuels and lubricants, medical supplies, engineer equipment, and motor maintenance equipment. Most troops of the assault echelons were to go ashore with two full canteens of water on each man’s belt. This practice had become general in the Southwest Pacific, since there was no means of ascertaining in advance how long it might take engineers to set up water supply points at the various objectives.54

Rapid air-base development was required at Morotai, since the Talaud operation was scheduled to follow within a month and Mindanao within two months. An immediate local requirement at Morotai was the quick construction of a fighter strip from which the island’s troops and development projects could be protected after carrier-based aircraft left the area. The latter program called for the construction of facilities on Morotai for two fighter squadrons by D plus 2, 17 September, and this objective required a fighter strip 5,000 feet long and 100 feet wide.

The long-range program provided for construction of another strip 7,500 feet long, with associated facilities, by D plus 25, 10 October. By that date the Morotai fields were to be ready to take care of fighters, medium bombers, night-fighters, and the large PB4Y reconnaissance bombers. By D plus 45, in time to support the landings on Mindanao, another strip 6,000 feet long and capable of extension to 7,000 feet was to be ready to provide space for more medium bombers and two groups of heavy (B-24) bombers. Other construction requirements included fuel storage facilities, wharves and jetties, storage warehouses, hospital facilities, light naval base facilities for PTs, roads, camps, and headquarters buildings for both ground and air units.55

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As had been the case in the Sansapor operation, an engineering officer of the Allied Air Forces (Brig. Gen. Donald R. Hutchinson (USA) for Morotai) was attached to the TRADEWIND Task Force for the sole purpose of selecting airdrome sites and establishing priorities for the construction of airfields and associated facilities. His decisions were to be binding upon the Commander, TRADEWIND Task Force. However, if General Hall thought that General Hutchinson’s selections might interfere with the ability of the task force to meet assigned construction target dates, the task force commander would refer any disagreements to ALAMO Force for decision.56