American victory The Battle of Wakde (Operation Straight Line) was part of the New Guinea campaign of World War II.

The operation involved an assault on the Japanese-held Wakde island group by a reinforced US infantry battalion, which was transported from a beachhead the Allied troops had established around Arara, on the mainland, the previous day.

[3][4] Initial Allied plans had called for the capture of Sarmi on the mainland, but aerial reconnaissance had later shown that it was unsuitable for heavy bombers.

The discovery that the airfields around Hollandia, on the Sentani plain, could not support heavy bombers, accelerated Allied plans to secure Wakde.

The Japanese had installed antiaircraft guns around the three airfields, and had around 11,000 troops in the Sarmi–Sawar–Maffin area, centered around Sarmi where Lieutenant General Hachiro Tagami's 36th Division had established a command post.

Nevertheless, the necessity to conform with plans in the central Pacific meant that it could be carried out no later than 17 May, with operations to capture Biak scheduled to take place 10 days later using most of the same landing craft.

The beach frontage on Wakde was considered too narrow to support a full regimental combat team; as a result, it was decided to carry out the operation in three phases.

[15] Early on 17 May, after a fifty-minute bombardment, three battalions from the 163rd Infantry Regiment were landed at a beachhead on the mainland around Arara, to the east of the Tor River.

Overhead a force of Allied fighters and medium bombers stood ready to provide close air support, but Japanese resistance was light, consisting of only rifle fire.

Indirect fire support was also provided from mortars and machine guns operated by the troops that had landed on Insoemanai the previous day.

By 9:25, the invasion force was ashore with two tanks (one of the others had been lost at sea, while the other had damaged during loading) which the Americans used to secure the beachhead, despite heavy fire from Japanese defenders which killed one of the company commanders.

By 13:30, the Americans reached the northern part of the airfield but failed to take the eastern side where the majority of the remaining Japanese forces were located.

Despite the delay in securing the island, throughout the afternoon stores and construction equipment were unloaded at the landing beach so that work could begin on the airfield.

Following the capture of the airfield, the surviving Japanese made their way to coral caves on the coast, delaying the Americans for several hours before finally being overcome.

The third day of the battle consisted mainly of mopping up operations by American forces who cleared up the last pockets of Japanese resistance in north-eastern corner of the island.

[30] The same day, the Kumamba Islands, to the northeast, were also occupied by Allied troops to install search radars to offer early warning to the base at Wakde.

Several Japanese snipers still remained on the island; they were eventually cleared out by Company L, which had been detached from the 3rd Battalion, 163rd Infantry to assist with mopping up operations between 22 and 26 May.

Later in the month radar and control facilities were established and more aircraft, including day and night fighters and heavy bombers, were flown in.

[26] American troops began their withdrawal from the island in January 1945, with the removal of some equipment at this time; however, operations on Wakde continued until November 1945.