Part II: TOENAILS Operation
Blank page
Chapter 1: Objective: New Georgia
Background of Munda1
Occupation of the Russells, following closely on the heels of the Guadalcanal victory, seemed to whet the appetite of Allied forces in the South Pacific for more action, more show-downs with the Japanese. In Admiral Halsey’s New Caledonia headquarters, optimism and enthusiasm ran high. Singleness of purpose and a spirit of camaraderie united all representatives on ComSoPac’s staff; and, charged by Halsey’s impatience to get on with the war, his staff busied itself planning for the next major offensive in the Solomons. The objective: seizure of the New Georgia Group.2 (See Map II, Map Section.)
A compact maze of islands separated by shallow, coral-fouled lagoons or narrow reaches of open water, the New Georgia Group lies on a northwest-southeast axis between Bougainville, 110 miles to the northwest, and Guadalcanal, 180 miles to the southeast. Nearly 150 miles long and 40 miles wide, it comprises 12 major islands outlined by many smaller islands and formidable reefs. A dense, forbidding jungle growth covers the rugged terrain and accents the abruptly rising, conical mountains which mark the volcanic origin of the group.
Largest island in the group is its namesake, New Georgia. It is hugged closely on the north by the islands of Wana Wana, Arundel, and Baanga and guarded to the southeast by Vangunu and Gatukai. Standing off to the south are Rendova and Tetipari, with two islands—Vella Lavella and Ganongga—in a line to the northwest. Gizo Island chains Vella Lavella to Wana Wana and blocks the southern end of Vella Gulf. Completing the New Georgia Group is the circular, 5,450-foot mountain peak, Kolombangara, which juts out of the sea between Vella Gulf and Kula Gulf, only a few miles northwest of Arundel.
The group centers on New Georgia. A tortuous, misshapen mass with a spiny ridge of peaks, it lies pointing north in a big inverted V, 45 miles in length and 20 miles wide. Its southern coastline is bordered for nearly 20 miles by Roviana
Lagoon, a coral-laced and treacherous stretch of water varying from one to three miles in width. Only small boats can safely trace a channel between the narrow openings in the reef and around the shallow bars of the lagoon. Viru Harbor, southeast of Roviana, is one of the few easy-access points on the southeast coast. A land-locked anchorage, it has an unobstructed but zigzag channel.
The entire east and northeast side of the island is reef-lined, with Marova and Grassi Lagoons bordering that coast almost as Roviana does on the south. As the coastline turns south at Visuvisu Point—apex of the V—Kula Gulf swells directly into three deep-water anchorages formed by jungle rivers rising in the mountains on the north coast. Rice Anchorage and Enogai Inlet are short and mangrove-lined with deep forest crowding the shores; Bairoko Harbor, deeper and longer, is partially blocked by reefs but is the best anchorage along the gulf. Past Bairoko, Hathorn Sound connects the gulf with the passage through to the south, Diamond Narrows. Only 224 feet wide at its narrowest point and 432 feet across at its widest, the Narrows separates New Georgia from Arundel and is the northern entrance to Roviana Lagoon. Its twisting channel is navigable, however, only by small boats.
The dank, oppressive nature of the island characterized even the life of the New Georgia natives. Theirs was a scrubby existence from small gardens, native fruits, some fishing, and occasional trading. One-time headhunters, they became aggressive sailors who moved from point to point through the lagoons by canoe, avoiding the rugged inland travel. As a result, they were, in 1943, excellent guides to the coastlines of the islands but almost completely ignorant of the interiors.
In November 1942, while still contesting possession of Henderson Field on Guadalcanal, the Japanese sought another airfield which would bring their fighter planes within shorter striking distance of the southern Solomons. They found it at Munda Point on New Georgia, about two-thirds of the way from Rabaul to Guadalcanal. It was a natural selection. Munda Point was relatively flat and could be reached from the sea only through one narrow break in its barrier reef, which was risky even for shallow-draft ships at high tide, or through several openings in the string of islets locking Roviana Lagoon to the island. An overland approach required an arduous jungle trek either from river inlets 10 miles to the north or from points to the east in Roviana. The position of the proposed airfield made an ally of the entire island, utilizing in protection all the reefs and islets which ringed New Georgia and the matted canopy of jungle growth which covered it.
The Japanese came to Munda in force on 13 November 1942. Their transports stopped off Munda reef late that day and, by early morning of the 14th, troops completed debarking by small boats. The occupation unit immediately sent out armed patrols to “subjugate” the natives and inform them of the Japanese intentions. Kolombangara, Rendova, Vangunu, and surrounding smaller islands were visited and quickly put under control. The construction of an airfield began with the arrival of additional troops and engineers on 21 November.
Coastwatcher Donald G. Kennedy at Segi Plantation on the extreme southeastern tip of New Georgia was one of the first
to hear of the occupation. In October, a month previous, when the Japanese first reconnoitered New Georgia, Kennedy organized a band of natives to help him defend his post. When they informed him of the Munda landing, he sent Harry Wickham, a half-native co-worker, to Rendova to watch Munda and report on the progress of the airfield.
Wickham’s report of Japanese activity at Munda was investigated immediately by Allied air reconnaissance. The first report, on 24 November, was negative. Photographs clearly showed a plantation area, a small cluster of buildings at Munda, and a similar cluster of buildings at Kokengola Mission north of Munda. There was no activity which could be classed as enemy, no evidence of airfield construction. Allied planes bombed the area anyway. It was a gesture of confidence in Kennedy and Wickham.
Then photo interpreters picked up interest. New buildings began to show up in later photo strips, and a strange white line appeared beneath the plantation trees. On 3 December, SoPac interpreters announced their discovery: a possible landing strip under construction. Two distinct strips, 125 feet wide and about 1,000 feet apart in a direct line with each other, were visible in the prints. One strip was about 175 feet long, the other about 200 feet. Natural camouflage, it was decided, partially shielded the construction. Two days later the field was 2,000 feet long. No trees had been cut down, but piles of either loose earth or coral appeared beneath each tree. New buildings, obviously control towers, had been built adjacent to the field. On 9 December, photos showed the field nearly clear, the trees apparently pulled up and taken away, and the holes filled in with coral. The Japanese, alerted by the continued interest of Allied planes over Munda, had abandoned further camouflage attempts.3
By 17 December, after only a month at Munda and despite multiple bombing raids, the enemy had an operational airstrip 4,700 feet long. A series of revetments and a turn-around loop eventually finished the field. An advance echelon of 24 aircraft was moved to Munda upon its completion, but all were destroyed or badly damaged by bombing raids within a week after arrival. Thereafter, the Japanese used the field mainly for servicing planes after raids on Guadalcanal and the Russells, and few pilots dared Allied bombings to tarry at Munda very long. Repair of the strip was easy; bulldozers quickly filled in the holes. Despite the rain of bombs and occasional shellings, the field was never out of operation longer than 48 hours.4
New Georgia, the Allies had decided, would be the target of the next offensive in the South Pacific. Munda airfield was the bull’s-eye. As a military prize, it held the enemy’s hopes for a re-entry into the lower Solomons and the Allied hopes for another step towards Rabaul.
New Georgia Reconnaissance5
Halsey had intended to be in New Georgia by mid-April. His planning date scrapped by the JCS and his offensive tied to construction of airfields at Kiriwina and Woodlark, the admiral waited for the go-ahead signal. While waiting, he sent reconnaissance patrols probing the Central Solomons.
Guadalcanal land operations had been plagued by a dearth of information on terrain and topography. New Georgia was likewise unmapped and hydrographic charts were badly out of date. Since aerial photography revealed only thick jungle growth, actual physical scouting by trained men was the only answer. A combat reconnaissance school with experienced Marine and Army personnel and selected coastwatchers as instructors was organized at Guadalcanal, and about 100 men were trained and formed into scouting teams. Halsey found their reports invaluable, and beginning with ELKTON planning, “never made a forward move without their help.”6
First terrain information on New Georgia had been received from a patrol of six Marines and a ComSoPac staff officer that had prowled Roviana Lagoon and the Munda area in late February, contacting coastwatchers, scouting and mapping trails, and selecting possible landing beaches. Their report helped the admiral reach a decision on hitting the Central Solomons and gave SoPac planners the information for tentative strategy.7
On 21 March, a group of Marine scouts drawn from the raider battalions and graduates of the combat reconnaissance school landed by PBY (Catalina flying boat) at Segi Plantation.8 With Kennedy’s natives as guides, the group split into patrols and set out to scout possible landing beaches, landmarks, and motor torpedo boat (MTB) anchorages. Traveling by canoe at night and observing during daylight hours, the patrols checked travel time from point to point, took bearings on channels, scouted enemy dispositions and installations, and sketched crude maps to help fill in the scanty information already available. One group had the mission of “collecting information about the Viru garrison, armament and accessibility to the area, both by way of direct attack up the harbor cliffs and by inland native trails through the jungle,”9 which marked
it as a possible target in the assault. Other patrols ranged from Roviana Lagoon to Arundel and Kolombangara, along the northern shore of New Georgia from Enogai Inlet to Marova Lagoon, and around the coast of Vangunu. Another patrol contacted the Rendova coastwatcher, Harry Wickham.10 The missions were virtually the same: to bring back all possible data on the enemy and terrain.
At this early date in the spring of 1943, tentative invasion plans envisioned a divisional landing at Segi Plantation followed by a sweep overland to capture Munda field. The patrol reports confirmed the growing suspicions of the ComSoPac war plans staff: Segi’s beaches would not accommodate a large landing force, and a sizable body of troops could not move through untracked jungle to Munda with any hope of success. Another method of attack would have to be developed.
The patrols continued to shuttle back to New Georgia for more information. Coastwatchers A. R. Evans on Kolombangara, Dick Horton and Harry Wickham at Rendova, and Kennedy at Segi played hosts to furtive guests who slipped in by native canoes from submarines, fast destroyers, or PBYs. The patrols searched openings in the barrier reef of Roviana, checked overland trails from Rice Anchorage on the north coast to Zanana Beach on the south in Roviana, and looked for easy access to Munda field. In this connection, Wickham—who had lived on New Georgia most of his life—”was particularly valuable.”11
The reports on Munda were discouraging. Hathorn Sound had no beaches and shallow landing craft could pass safely only halfway through Diamond Narrows.12 LSTs might possibly skirt the west shore of Baanga Island to get to Munda, but it would be a hazardous, obstacle-lined trip. Crossing the reef at Munda bar was another risk. Soundings indicated that the opening, through continued coral deposits, had become more shallow and restricted than admittedly outdated reports indicated. A direct assault over Munda bar, the closest entrance to Munda, was patently the most dangerous course and held the least chance of success.
Final assault plans were a concession to the terrain. They provided for landings off-shore from Munda, followed by a troop buildup on New Georgia and then a strong attack on the airfield from all sides. The last reconnaissance patrols went into the New Georgia Group on 13 June. Landing at Segi they took off in log canoes for the four landing spots finally selected: Rendova, Rice Anchorage, Viru Harbor, and Wickham Anchorage. Teams of Marine Corps, Army, and Navy officers studied the designated beaches and sought artillery positions, observation posts, water points, bivouac areas, and interior trails. Some of the patrols skirted Japanese defenses, noting the strength and habits of the enemy, before striking inland for terrain information. When the teams paddled back to Segi, some of the members stayed behind with natives to
guide the landing parties to the beaches with lights flashed from the shore.
Awaiting Assault13
Munda assumed a new role in enemy strategy during the spring of 1943. Instead of the proposed springboard for recapture of Guadalcanal, it became a keystone in Japan’s decision to build up the Lae-Salamaua defense line while maintaining the Solomons as delaying positions.
Japanese engineers, after rushing Munda into completion, hurried to Kolombangara to construct another field at Vila Plantation on the southeast shore. Here they did not attempt concealment. The task went ahead despite almost daily bombings and occasional naval bombardments. The enemy now had two strips from which they could stage attacks against Allied positions on Guadalcanal and the Russells; but the air over The Slot was a two-way street, and most of the traffic was from Henderson Field.
Buildup of troop strength in the Vila-Munda area was steady but slow. Air supremacy was still contested, but the initiative was with the Allies. Japanese plans for reinforcing the Central Solomons were slowed by the continual harassment from planes of Commander, Aircraft Solomons (ComAirSols), and the enemy was eventually reduced to scheduling troop transfers “from the end of the month to the beginning of the following month to take advantage of the new moon.”14 Then, too, the transport losses in the Battle of the Bismarck Sea on 3 March and the steadily mounting attrition of naval craft from air attacks was slowly sapping Japanese sea power.
By the end of April, land defenses in the Central Solomons had been strengthened with Army and Navy troops, and additional reinforcements were standing by in the Buin-Shortland area for further transportation. The 8th Combined Special Naval Landing Force (CSNLF), which included the Kure 6th Special Naval Landing Force and the Yokosuka 7th SNLF was the Navy’s contribution to the defense of Vila-Munda.15 After Japan lost the initiative in the Pacific, these amphibious assault troops were changed to defense forces. Named for the naval base at which the unit was formed, an SNLF generally
included: a headquarters unit; two rifle companies; a heavy weapons company with howitzer, antitank, and machine gun units; an antiaircraft company; a heavy gun or seacoast defense unit; and medical, signal, supply, and engineer troops.
The Yokosuka 7th landed at Kolombangara on 23 February with 1,807 men, and was followed on 9 March by the Kure 6th with 2,038 men. This unit went into positions between Bairoko and Enogai and around the airfield at Munda. Rear Admiral Minoru Ota, commanding the 8th CSNLF, assumed responsibility for the defense of the New Georgia sector.
By prior agreement between the Seventeenth Army and the Eighth Fleet, Army and Navy strength in the Central Solonmons was to be about even. After sending the 8th CSNLF to the New Georgia area, the Navy was determined to hold the Army to its end of the bargain. Following a number of conferences, the Army reinforcements began arriving in late March. The original force at Munda consisted of two companies from the 2nd Battalion. 229th Regiment of the 38th Division, with two antiaircraft battalions for protection for the naval base construction troops. Kolombangara was garrisoned early in 1943 with troops from the 51st Division including an infantry battalion, an artillery detachment, and engineer and air defense units.
The remainder of the 229th Regiment at Buin, with supporting troops, began to filter into New Georgia late in April and the 51st Division troops on Kolombangara were relieved. The 229th moved to the Munda airfield area, and a battalion from the 13th Infantry Regiment, 6th Division, took over actual defense of Kolombangara. As opportunities arose, the Japanese moved in more troops.
Guadalcanal had been a well-learned—albeit painful—lesson. The reinforcement of the Vila-Munda area reflected Japan’s new strategy:–
Our fundamental policy was to bring the desired number of troops into strategic key points before the enemy offensive, in spite of manifold difficulties; and in event of an enemy offensive, to prevent our supply transportation from being hampered; to throw in our entire sea, land, and air strength at the first sign of an enemy landing to engage it in decisive combat; and to secure completely the strategic key positions linking the Central Solomons, Lae, and Salamaua, which formed our national defense boundary on the southeastern front.16
On New Georgia, the Japanese prepared defenses for all eventualities. Munda Point and the airfield vicinity bristled with antiaircraft and artillery weapons. The enemy did not discount the threat of a direct assault over Munda bar and sited some of their armament to cover that approach; but the bulk of the weapons pointed north toward Bairoko—from which an overland attack might come—and toward Laiana Beach on Roviana Lagoon—where an attack seemed logical. The Japanese believed, however, that the next Allied objective was to be Kolombangara in an attempt to attack Munda from the rear; so Vila likewise was prepared to repulse any assault. Increased Allied air activity, the presence of a great number of troop transports in the Guadalcanal area, and increased reconnaissance convinced the enemy that an attack was imminent. Their intelligence reports of about 50 cargo-type airplanes at Henderson Field also prompted speculation on the possibility of airborne operations against Vila-Munda.
With both Army and Navy troops occupying identical Central Solomons positions, a more unified command arrangement was sought. Admiral Ota, the senior commander in the area, had been responsible for both Army and Navy land defenses in the Vila-Munda area. On 2 May, however, Imperial Headquarters directed that a command post be established in New Georgia, and on 31 May, Major General Noboru Sasaki of the 38th Division arrived at Kolombangara to head the new Southeast Detachment, a joint Army-Navy defense force. Administratively attached to the Seventeenth Army but under the operational command of the Eighth Fleet, General Sasaki was assigned responsibility for all land defenses in the New Georgia sector and command of all Army troops in the area. Admiral Ota, still in command of Navy troops, was directed to give him fullest cooperation. It was a command structure which criss-crossed Army and Navy channels, but with Sasaki’s assignment spelled out, and with Ota’s cooperation assured, a unified force was established.
By late June, as Japan waited for an Allied thrust she believed was coming, the defensive positions in the New Georgia Group were set. To obtain greater coordination, General Sasaki divided his defense area into three zones of responsibility: the Central (Munda); the Western (Kolombangara); and the Eastern (Viru-Wickham). The task of defending Munda Point he gave to Colonel Genjiro Hirata and the 229th Regiment, augmented by two batteries of the 10th Independent Mountain Artillery Regiment. Air defense would be provided by the 15th Air Defense Unit which combined the 41st Field Antiaircraft Battalion (less one battery), the 31st Independent Field Antiaircraft Company, the 27th Field Machine Cannon Company, and the 3rd Field Searchlight Battalion (less one battery). One company of the 229th Regiment was dispatched to Rendova.
To aid Sasaki in the defense of the airfield, Admiral Ota established three seacoast artillery batteries at Munda with 140-mm, 120-mm, and 80-mm guns. Also based there was an antiaircraft machine gun company of the Kure 6th SNLF, the 21st Antiaircraft Company and the 17th and 131st Pioneers (labor troops). Ota also sent a rifle company from the Kure 6th to Rendova. The remainder of the Kure 6th, under Commander Saburo Okumura, was to defend the Bairoko Harbor area. Kolombangara’s defense was entrusted to a battalion of the 13th Regiment, reinforced by a battery of the 10th Independent Mountain Artillery. Air defense of Vila airstrip rested with the 58th Field Antiaircraft Battalion (less one battery), the 22nd and the 23rd Field Machine Cannon Companies, and a searchlight battery. The main detachments of the Yokosuka 7th SNLF and the 19th Pioneers were also based on Kolombangara.
Viru Harbor was garrisoned by the 4th Company of the 229th, less one platoon which went on to Wickham Anchorage to augment a seacoast defense battery from the Kure 6th. To complete the defensive picture, lookout platoons were scattered about the coastline of New Georgia and on some of the small adjacent islets to act as security detachments.
In all, as Sasaki’s reinforcement and defense plans raced right down to the wire with Allied offensive preparations, the Japanese had about 5,000 Navy and 5,500
Army troops in the New Georgia-Kolombangara area. Although the 8th CSNLF was not combat tested, the 229th Regiment and the 13th Regiment were another matter. The 229th had participated in the capture of Hong Kong before taking part in the occupation of Java. Committed to combat again, the regiment had one battalion nearly annihilated on New Guinea and another battalion suffered heavy casualties at Guadalcanal. Reinforced by fresh troops at Rabaul and Bougainville, the survivors had been formed into new battalions to join the 2nd Battalion at New Georgia. The elements of the 13th Regiment, before being sent to Kolombangara, were part of the 6th Division which garrisoned the Northern Solomons. One of Japan’s oldest divisions, the 6th, was likewise hardened by combat in China before being sent to the Solomon Islands.
Sea Offensives17
Expanding sea and air offensives by the Allies in the late spring of 1943 had a definite bearing on Japan’s outlook toward her defenses in the South Pacific. Widening the scope of the war, a large-scale bombing attack in mid-May plastered the Japanese-held atoll of Wake in the Central Pacific. This strike followed a landing in the Aleutians on 11 May by U.S. Army troops covered by naval forces. The enemy believed that the counterlandings in the North Pacific were a direct threat to the Home Islands, and plans for the southeast area were immediately curtailed. About 20 per cent of the troops earmarked for the Solomons and New Guinea were shifted to the northeast area; and Admiral Mineichi Koga, successor to Admiral Yamamoto, pulled his Combined Fleet headquarters out of Truk and moved to Tokyo so that he could better control operations throughout the Pacific. His main fleet units, however, remained at Truk.
True to his promise to the JCS at the time of the 28 March directive, Admiral Halsey kept the pressure on the Japanese in the Central Solomons. Under the pounding of bombs and sea bombardments, the Vila-Munda area never had the opportunity to develop past its use as a refueling point for enemy planes. The Allied strikes scored few casualties among the Munda defenders, relatively secure in underground defenses near the airfield, but kept enemy engineers busy repairing the cratered runways. The attacks lowered morale, however, by keeping the Japanese “sleepless and fatigued,”18 and occasional hits were scored on fuel and supply dumps. Prior to May, Munda and Vila had taken nearly 120 bombing raids, and four major naval bombardments had rained shells on the two airfields.
The Tokyo Express—fast destroyers carrying troops and supplies to the New Georgia Group—still steamed on. The Allies found they could not possibly cover all avenues of supply, and that to halt the traffic entirely would require more planes
and ships than South Pacific forces could muster at this stage of the war. On 6 May, however, the express runs were abruptly, if only temporarily, disrupted. Rear Admiral Walden L. Ainsworth, heading a Third Fleet task force of three cruisers, five destroyers, and three converted destroyer-mine layers, steamed up the gap between Gizo and Wana Wana Islands into the Vella Gulf. As Ainsworth’s cruisers and four destroyers blocked the northern entrance to Vella Gulf, the three mine layers escorted by a radar-equipped destroyer laid three rows of mines across the straits between Kolombangara and Gizo. Then the entire force turned for home bases at Guadalcanal. (See Map II, Map Section.)
Dividends were almost immediate. The next night, four Japanese destroyers slipped into Blackett Straits with Vila as their destination. They never reached it. The trap was sprung. Blundering into the mine field, one ship went down almost immediately; two others were badly damaged. The fourth ship stood by to pick up survivors. And that’s the way Allied planes, somewhat delayed by adverse weather, found them the next day. The two damaged ships were sunk by bombs, but the fourth ship, heavily bombed and strafed, managed to limp back toward Bougainville. Gleeful coastwatchers radioed the box score to Guadalcanal.
Heartened by the success, the Third Fleet planned another surprise. This time, Vila would be shelled as the northern entrance to Kula Gulf was mined. On the night of 13 May, Admiral Ainsworth led a force of three cruisers and five destroyers in firing runs past Vila, steaming in from the north, while a destroyer and three fast mine layers planted mines off the east coast of Kolombangara. As each of Ainsworth’s ships completed her run past Vila, she turned and pumped heavy fire into the Bairoko and Enogai-Rice Anchorage areas.
At the same time, a force of one cruiser and three destroyers plastered Munda on the opposite side of New Georgia. The airfield had not been included in the original bombardment plans, but a last-hour switch in orders—accomplished by dispatch and a message drop from planes to the ships designated—had added that stronghold. Vila was hit by a total of 2,895 six-inch and 4,340 five-inch shells, Munda by 970 six-inch and 1,648 five-inch. The operation was covered by an air strike in the Northern Solomons and additional fighter planes flew cover and reported bombardment results.
The mine-laying did not produce the earlier results. It slowed the Japanese supply chain by forcing it to be more cautious, but it did not halt it. The bombardment was a bigger disappointment. Less than 12 hours after the last shell had been fired, a flight of 26 Japanese fighters staged from Munda-Vila was chasing the attack force back to Guadalcanal. Coastwatchers radioed the warning; 102 Allied aircraft formed a welcoming committee. Seventeen enemy planes were reportedly shot down; 16 of them were claimed by Marine fighters. Five Allied planes and three pilots were lost in the action. The bombardment was the last scheduled before the actual invasion; the results, it was apparent, were not worth the price. A harassing bombardment, CinCPac later advised, was not justified when “all ships were subjected to the hazard of enemy MTB and SS [submarine]
attacks with no prospect of equal opportunity to damage the enemy.”19
Air activity increased during June. Airfields in the Russells gave the Allies a shorter range to targets in the Northern and Central Solomons, as well as providing another launching area for getting planes into the air to repel attacks. Attracted by the concentration of shipping in the Guadalcanal area, the Japanese tried a new one-two punch of heavy flights of fighters followed by large numbers of bombers, but three major strikes on 7, 12, and 16 June resulted in staggering losses. The enemy had hoped to break even in fighter tolls, which would then give their bombers opportunity to attack unmolested. The maneuver boomeranged. Each time, ComAirSols was able to meet the threat with from 105 to 118 aircraft and in the three strikes, a total of 152 enemy airplanes was claimed. The Allies lost 21.
Preparing to Strike20
The assault of New Georgia, viewed in optimism contagious at the time, seemed an easy assignment despite the inaccessability of Munda. Reconnaissance had virtually pinpointed Japanese strong points, and the combat effectiveness of the Vila-Munda airfields had been reduced considerably by the Allied pounding. Intelligence sources, which later proved remarkably accurate, estimated that there were only about 3,000 Japanese at Munda, with another 500 troops at Bairoko and a detachment of 300 men at Wickham Anchorage and about 100 more at Viru Harbor. The bulk of the forces, estimated at 5,000 to 7,000 troops, was on Kolombangara, together with an additional 3,000 laborers.
Japan’s reinforcement ability from points in the Northern Solomons was noted, but there was no ready estimate of the numbers available for quick assignment to combat. Her sea strength in the Solomons was believed to be 6 destroyers, 5 submarines, and 12 transports, with a cruiser, 5 destroyers, 7 submarines, and 25 attack transports at Rabaul. Japanese air strength was put at 89 land-based aircraft in the Solomons with another 262 at Rabaul. While troop estimates were near the actual enemy totals, ComSoPac guesses on air and sea numbers of the enemy were low. The entire Eighth Fleet was in the Shortlands area, while a part of the Combined Fleet at Truk was committed to lend assistance in Southeast Area operations. The Japanese Navy had 169 land-based planes available for combat from a total of nearly 300 deployed in the Bismarck Archipelago and the Northern Solomons. The Eighth Area Army had about 180 aircraft attached directly to it; however, most of these were supporting operations against the Allies in New Guinea.
The target had been marked. Early in June, Admiral Halsey published his orders for the seizure and occupation of New Georgia. The improbable code name TOENAILS masked Halsey’s part in the CARTWHEEL offensive. The missions: capture Wickham Anchorage and Viru Harbor as small-craft staging areas; seize Segi Plantation as a possible airfield site; seize Rendova as a base for the neutralization of Munda by artillery fire. Orders for the actual assault of Munda airfield
would be issued by ComSoPac after the successful completion of the first phase of TOENAILS.
Task units of the Third Fleet were assigned covering missions which would insure success of the operation by blocking any enemy force attempting to disrupt the landings with a counteroffensive. While one force of destroyers and cruisers moved in to mine the main sea channels around the Shortland Islands, another heavier force of battleships and destroyers was to stage a bombardment of Japanese strong points in the Northern Solomons and Shortlands. Air units of the South Pacific Air Command, under Vice Admiral Aubrey W. Fitch, were assigned strikes against shipping in the Shortlands area and bombing missions on airfields on Bougainville. Carrier air groups were to intercept any enemy ships or aircraft heading for the New Georgia Group. SoPac submarines were to range into the Northern Solomons for interception and early warning of any Japanese force, and destroyer units would provide close-in support for the transport groups engaged in the actual landing operations. Thus, with Admiral Halsey’s forces guarding the northern and eastern approaches to New Georgia, and General MacArthur’s operations in New Guinea shielding the western flank, the assault forces could proceed with the seizure of TOENAILS objectives.
The Army’s 43rd Infantry Division, part of Major General Oscar W. Griswold’s XIV Corps, was named as the assault and occupation troops. The 2nd Marine Aircraft Wing headquarters under Brigadier General Francis P. Mulcahy was assigned to direct tactical air support over the target during the operation. Rear Admiral Turner, commander of amphibious forces in the South Pacific, was given overall responsibility for New Georgia operations. Detailed planning for the actual seizure and occupation of the objectives outlined in Halsey’s broad plans would be Turner’s job.
To accomplish the TOENAILS missions, Turner divided his command into two units. He would personally direct the larger Western Force in the main landing at Rendova and would be responsible for movement of troops and supplies to the objective and for their protection. The Eastern Force, under the direction of Rear Admiral George H. Fort, would seize Viru, Segi Plantation, and Wickham Anchorage. Admiral Fort would be responsible for movement to these targets and for embarking troops and supplies from the Russells for subsequent operations.
Admiral Turner’s ground commander, Major General John H. Hester, headed the New Georgia Occupation Force (NGOF). Its combat units consisted of Hester’s own 43rd Infantry Division, including the 172nd and 169th Regiments and one battalion of the 103rd Regiment; the Marine 9th Defense Battalion; the 136th Field Artillery Battalion from the 37th Infantry Division; the 24th Naval Construction Battalion (NCB); Company O of the Marine 4th Raider Battalion, the 1st Commando, Fiji Guerrillas;21 and assigned service troops.
Fort’s Eastern Force would include the 103rd RCT (less the battalion with Nester); Companies N, P, and Q from the 4th Raider Battalion; elements of the 70th Coast Artillery (Antiaircraft) Battalion; parts of the 20th NCB; and service units.
The landing force would be headed by Colonel Daniel H. Hundley, commanding the 103rd RCT. Selected as ready reserve for the operation was the 1st Marine Raider Regiment (less the 2nd, 3rd, and 4th Battalions), commanded by Colonel Harry B. Liversedge. The Army’s 37th Infantry Division (less the 129th RCT and most of the 148th RCT) would be in general reserve at Guadalcanal, ready to move on five-days’ notice.
Execution of the assigned tasks looked easy. Turner’s original concept was to seize the southern end of New Georgia simultaneously with Rendova. Artillery based on Rendova and offshore smaller islands would soften Munda field while the buildup of assault forces began. Four days later, it was planned, Munda would be attacked through Roviana Lagoon and over Munda Bar, while Bairoko would be struck either from the Russells or by a force hitting overland from Roviana Lagoon. This maneuver would block reinforcements for the airfield. Capture of Munda would then trigger the next shore-to-shore jump to Kolombangara, the last phase of Operation TOENAILS.
These were the first plans. ComSoPac orders stressed their successful completion with a minimum of forces. It could not be foreseen at the initial planning conferences that, before Munda could be captured and the New Georgia Group occupied, elements of four infantry divisions would be committed and extensive changes in plans would be required. The problems mounted early. Laiana Beach on Roviana Lagoon east of Munda was heavily defended, although the best landing area. The channel through Roviana, scouted from canoes, was too shallow for LCMs. The islands near Rendova originally considered for artillery positions were not within effective 105-mm howitzer range of Munda airfield. And coastwatcher reports indicated that the enemy—despite Allied efforts—was slipping reinforcements into the Vila-Munda area. Further, a reconnaissance team reported that a strike at Bairoko from Roviana was impossible within the time limits planned.
The solutions plagued Turner’s staff. Zanana Beach, about 5,500 yards east of Laiana, was smaller but virtually undefended, the scouts reported. While it would hold only a few landing craft, the Piraka River mouth 1,000 yards farther east could permit beaching of additional boats. Hester decided on Zanana as his landing beach, and Turner gave his approval. Reaching Zanana would be a problem, however. Landing boats would have to slip through narrow, coral-choked Onaiavisi Entrance that threaded between the small offshore islands and then follow a twisting channel to the beaches. The selection of Zanana was based as much on its undefended nature as on its capability of being reached by LCMs. It had, however, one apparent drawback. The attacking troops would be unloaded at a considerable distance from their objective. (See Map 5.)
The planning problems were unexpectedly magnified by an emergency. An urgent call for assistance by Coastwatcher Kennedy at Segi resulted in the premature commitment of two Marine raider companies and two companies from the 103rd RCT on 21 June. Admiral Turner made the decision. The speedup in schedule upset previous planning, but it was deemed necessary. It required a change in basic
strategy, a shuffling of troops, a change in the transport plans—and some around-the-clock supply duty by the Marine 4th Base Depot in the Russells—but the decision retained possession of Segi for the Allies until the actual New Georgia invasion.22
General Hester, who would direct the operations ashore, continually faced thorny problems. To deal with the mounting complexities, he delegated the planning for the Rendova landings to a 43rd Division staff headed by his assistant division commander, Brigadier General Leonard F. Wing. A second staff, the NGOF staff, completed the New Georgia attack planning. Hester retained command of both staffs. The final assault plans evolved from the best solutions to a multiplicity of problems. In the scheme of maneuver, part of the Western Force would hit at Munda through Onaiavisi Entrance with two regiments landing at Zanana and pivoting to the west in an overland attack with one flank resting on the lagoon. This force, designated the Southern Landing Force, would be commanded initially by General Wing.
Liversedge’s raiders—now titled the Northern Landing Group—would strike directly at Bairoko from Kula Gulf. This would be coordinated with the landings at Zanana and would block reinforcements to Munda. It was not expected that the Munda forces would attempt to reinforce the Bairoko defenders. This half of a pincer movement faced one handicap; the area was not as well scouted as that of Roviana Lagoon. The Hester plan of attack envisioned a short campaign during which the Japanese would be caught between a hammering force from the south and a holding force in the north. Thus, the enemy would be pushed back towards an area where, ringed by Allied troops, they could be pounded into submission by aircraft and Rendova-based artillery. To insure success, additional 43rd Division artillery (the 192nd and the 103rd Field Artillery Battalions) was added to the NGOF.
D-Day assignments were set. Troops of the 172nd Infantry would seize two small islands guarding the approaches to Rendova and then establish a beachhead on Rendova itself. Through the secured passage, Hester and Wing would funnel the rest of the landing force, with the 103rd Infantry given the task of expanding the beachhead and mopping up the island, reported to be lightly defended. Simultaneously, two companies of the 169th Infantry would land on islets flanking Onaiavisi Entrance and a detachment of Fiji guerrillas and Marine raiders would mark the channel with buoys to Zanana Beach and the nearby Piraka River. Four days later, the 172nd Infantry would make the Rendova-Zanana move and establish a beachhead for the landing the following day of the 169th Infantry from the Russells. The 169th was to move inland to the north of the 172nd, then face to the west. This would put two regiments abreast, ready to launch an attack from a line of departure along the Barike River, some 2,000 yards closer to Munda. Artillery on the offshore islands and Rendova would support the attack. Five days later, it was planned, the 3rd Battalion of the 103rd Infantry and the eight tanks of the Marine 9th Defense Battalion would cross Munda bar for the final, direct assault on Munda airfield.
Marine Corps Support23
Marine units which were to participate in the seizure of Munda were fulfilling a number of tasks and training missions prior to the operation. The actual job of pushing the enemy from New Georgia belonged mainly to General Hester’s 43rd Division; contributions to the campaign by the Marine Corps would be in support of the main effort. The 9th Defense Battalion was given a dual mission of making enemy positions on Munda untenable by artillery fire and of providing antiaircraft protection for the landing forces. The 1st Marine Raider Regiment, at first intended as a reserve element, was thrust into an active role with its mission of wedging a block on Dragons Peninsula between the Munda defenders and reinforcements at Bairoko Harbor.
Colonel Liversedge’s raiders were a cocky, confident group which prided itself on being a volunteer unit within a volunteer Corps. Carrying only 60-mm mortars and light machine guns as supporting weapons, each battalion was generally organized with four rifle companies, an engineer and demolition platoon, and a headquarters company. Smaller in authorized strength than the regular Marine infantry battalion, the actual strength of the raider battalions varied between 700 and 950. Specially trained for jungle fighting, amphibious raids, and behind-the-lines guerrilla action, the raiders had participated in the Tulagi- assault, a hit-and-run raid at Makin Island in the Gilberts, the defense of Midway, and jungle warfare on Guadalcanal. These Marines thus brought to the New Georgia campaign considerable combat experience plus the conviction that the fighting ahead would follow no orderly lines of battle. The vexing problems presented by the jungle in maintaining communications and supply would demand the utmost in courage, ingenuity, and stamina; but the raiders felt up to the task. They were firm in the belief that these difficulties, inextricably complicated by the terrain and enervating climate, could be overcome by their tough physical training, combat experience, and high morale.
At the time of consolidation of the four battalions under one command on 15 March 1943, the raiders were scattered throughout the South Pacific with regimental headquarters and the 2nd and 4th Battalions at Espiritu Santo, the 1st at Noumea, and the 3rd in the Russells. Upon assignment to the TOENAILS operation, the regiment (less the 2nd and 3rd Battalions) moved to Guadalcanal, arriving there the first week in June. Here the raiders had only a few days to go over their orders, iron out organizational kinks, and practice as a single unit before the 4th Battalion was abruptly assigned to Kennedy’s assistance.
The 9th Defense Battalion commanded by Lieutenant Colonel William J. Scheyer, had particular reason to be proud of its assignment in the TOENAILS operation. With a quick conversion of its seacoast batteries to field artillery units, the 9th would be in an offensive role against the Japanese at Munda and the prospect pleased the entire battalion. One of 14 such highly specialized defense forces scattered from Cuba to New Zealand, the 9th was providing antiaircraft protection for Guadalcanal forces when picked for the New Georgia offensive. Activated early in 1942, the 9th trained extensively in Cuba before arriving at Guadalcanal on 30 November 1942. The battalion was in defensive action almost immediately, and its 90-mm batteries bagged a total of 12 enemy aircraft in the following months.
Organizational changes had to be made, however, to get the unit ready for its part in the capture of Munda. In 21 days, the seacoast batteries, augmented by 145 new men, were trained in field artillery fire direction methods and had test-fired newly arrived 155-mm pieces. The change from seacoast sights to field artillery sights and different fire commands was only part of the problem, though. As one battalion officer reported:–
Our problem was not one of training but one of obtaining the necessary equipment and ammunition so that a relative calibration could be fired to obtain some idea as to the relative velocity errors of the new weapons in order to mass their fires. We were plagued throughout the operation with this equipment and ammunition problem. When the ammunition did arrive from Noumea, there were 19 different powder lots in a shipment of 25 rounds. Obviously, calibrations could not be conducted with propellants of different powder lots and about all that was accomplished was test firing of the weapons so that the men could be familiar with them.24
The battalion, with an assist from its relieving Army unit, the 70th Coast Artillery (Antiaircraft) Battalion, picked up new 90-mm antiaircraft guns equipped with power rammers and remote control equipment in exchange for the old guns which were left in position. In addition, power-operated mounts were placed on spare 20-mm guns, increasing speed and efficiency over the standard mounts which were pedal-operated. The 9th also borrowed 12 amphibian tractors from the 3rd Marine Division, and Griswold’s XIV Corps exchanged new trucks and jeeps for old. As the 9th readied itself for its mission, its armament included a platoon of 8 light tanks, 8 155-mm guns, 12 90-mm guns, 16 40-mm guns, 28 20-mm guns, and 35 .50 caliber antiaircraft machine guns.
Relieved of its defensive role on Guadalcanal on 17 June, the battalion spent the remaining time in familiarization firing of weapons, gun drills which included reconnaissance, selection, and occupation of positions, and practice landings. Gunners and loaders from the antiaircraft batteries turned riflemen to give the tankmen practice in tank-infantry tactics. The amphibian tractors were test-loaded until a loading arrangement was obtained which would provide enough 40-mm, 20-mm, and .50 caliber ammunition for all three types of antiaircraft guns to go into action immediately upon landing. The 9th also took advantage of a liberal interpretation of its orders to get more ammunition for the 90-mm batteries. Loading orders specified three units of fire were to be carried. Since an Army unit of fire for the 90-mm guns was 125 rounds and a Marine unit of
fire 300 rounds, the 9th interpreted the orders to mean Marine Corps units of fire and carried the extra ammunition. Despite some misdirected trucks and some confusion as to unmarked dock areas, the eager 9th was aboard ship and waiting hours before the scheduled departure.25
In time, elements of the 10th and the 11th Defense Battalions would be called upon to augment the 9th in its mission at Rendova and Munda, but until placed on alert, they continued to assist in the defense of Guadalcanal and the Russells. A fourth unit, the 4th Defense Battalion, which had been in the New Hebrides before going to New Zealand, was soon to be recalled to Guadalcanal for participation in the final phase of the campaign in the Central Solomons. The employment of these battalions as offensive elements instead of defense forces illustrated the change in the character of the war.
Although not carried on the orders as part of the New Georgia Occupation Force, another Marine Corps element was to provide invaluable support to the operation. This was the 4th Base Depot, a supply organization which had been activated at Noumea on 1 April 1943 as the direct result of a logistics logjam in the South Pacific. Prior to the New Georgia operation, the Army had responsibility for unloading all supplies, but as the size of forces in the area grew, the inadequate and limited facilities and the understaffed corps of laborers in the Pacific were strained to maintain a smooth and uninterrupted flow of necessary supplies. Despite the Army’s best efforts, the result was a confused backlog of equipment and supplies at New Caledonia and Guadalcanal which almost sidelined the New Georgia operation.
Shipping to the lower Solomons, except for vital aircraft engines and spare parts, motor transport spare parts, rations, and medical supplies, was curtailed for a time, and all other goods were routed to Noumea for transshipping to Guadalcanal on call. Supplies necessary for the New Georgia operation were then plucked from the stockpiles at Noumea and assembled at Guadalcanal. Other war materials were directed to the Southwest Pacific forces, added to the growing dumps in the New Hebrides, or stored in New Zealand.
The 4th Base Depot, under the command of Colonel George F. Stockes, and with personnel gleaned from the 1st, 2nd, and 3rd Base Depots and the Marine 12th Replacement Battalion, moved with 61 officers and 1,367 men to Guadalcanal to help relieve the congestion. Placed under the command of the XIV Corps, it was ordered by Griswold to relieve the service elements of the 43rd Infantry Division in the Russells, and to bring order out of the general confusion. The 4th Base Depot was then to receive and store all supplies for the New Georgia operation and the Russells garrison; maintain a 60-day level of supplies for TOENAILS forces; and handle and load aboard ships all supplies as called for by the 43rd Division and supporting troops on New Georgia.
The assignment was insurance that logistical problems would not slow the attack. It was a timely move. Shortly after the 4th Base Depot began working on the jumbled stockpiles of material, the initial phase of TOENAILS began with the Segi Plantation occupation, and the Marines were called upon for supply assistance.
By the time the main operations started at Rendova, the depot had the necessary material ready for forward movement, and in the following months it funneled a steady stream of lumber, cement, ammunition, rations (including fresh fruit and meats), clothing, tires, spare parts, gasoline, lubricants, sand bags, tents, engineer equipment, post exchange items, and many other types of supplies into New Georgia.
For Marine Corps aviation units, establishment of an exact date for the start of the New Georgia campaign is difficult. The conflict for air superiority was constant and continuing, not boundaried by beachheads or D-Days. The struggle for undisputed possession of the lower Solomons phased directly into the New Georgia campaign, and it is hard to differentiate between the squadrons which supported the consolidation of the Solomons and those which directly took part in the capture of Munda airfield. In any event, most Marine squadrons then based at Guadalcanal or in the Russells participated in both campaigns, either in part or in whole.
Rear Admiral Marc A. Mitscher, as ComAirSols, had an Allied force of 627 planes with which to support operations in the Central Solomons. It was a composite of Marine, Army, Navy, and New Zealand aircraft, and included 290 fighters, 94 scout bombers, 75 torpedo bombers, 48 heavy bombers, 26 medium bombers, 30 flying boats, 24 seaplanes, and a miscellany of 40 search, rescue, and transport planes.26
Although plans for garrisoning New Georgia were still in the tentative stage, a number of Marine squadrons were to be based at Munda airfield following its capture and would become an integral part of the New Georgia Air Force. Prior to the campaign, however, this term was a paper designation for a forward echelon of the 2nd Marine Aircraft Wing, attached to the NGOF; its commanding officer, General Mulcahy, would “exercise operational control of aircraft in flight assigned to air cover and support missions in the New Georgia area.”27 Requests for air support strikes would be made to liaison parties with each landing force, and General Mulcahy as ComAir New Georgia would approve, disapprove, or modify. It was, in effect, a fighter-bomber direction center for both air defense and direct support missions. Control of the assigned aircraft would pass to ComAir New Georgia when the planes took off from their home fields.
Available for such tactical air support missions as would be assigned them in the months ahead were seven Marine fighter and four scout bomber squadrons, backed up by three utility squadrons and a photo reconnaissance detachment. For the most part, though, the role of the Marine squadrons in the seizure of Munda is part of the bigger story of how Allied air strength reduced the Japanese stronghold at Rabaul to impotency. This will be related in Part V of this volume.28