The
2/6th Independent Company arrived in Port Moresby from Australia on 2 August 1943. The unit had fought in Papua in 1942 in the
Battle of Buna–Gona and had since conducted intensive training in Queensland. The company was under the command of
Captain Gordon King, who had been its second in command at Buna. King received a warning order on 12 September alerting him to prepare for the capture of Kaiapit, and had access to detailed aerial photographs of the area. .|alt=A man in slouch hat and shirt wearing earphones. In front of him are two boxes, the smaller on top of the larger. An independent company at this time had a nominal strength of 20 officers and 275 other ranks. Larger than a conventional infantry company, it was organised into three platoons, each of three sections, each of which contained two subsections. It had considerable firepower. Each subsection had a
Bren light machine gun. The gunner's two assistants carried rifles and extra 30-round Bren magazines. A sniper also carried a rifle, as did one man equipped with
rifle grenades. The remaining four or five men carried
Owen submachine guns. Each platoon also had a section of
2-inch mortars. The company was self-supporting, with its own engineer, signals, transport, and quartermaster sections. The signals section had a powerful but cumbersome
Wireless Set No. 11 for communicating with the 7th Division. Powered by
lead-acid batteries which were recharged with petrol generators, it required multiple signallers to carry and the noise was liable to attract the attention of the enemy. The platoons were equipped with the new
Army No. 208 Wireless Sets. These were small, portable sets developed for the communication needs of units on the move in jungle warfare. However, the 2/6th Independent Company had not had time to work with them operationally. For three days in a row, the 2/6th Independent Company prepared to fly out from Port Moresby, only to be told that its flight had been cancelled due to bad weather. On 17 September 1943, 13 Dakotas of the
US 374th Troop Carrier Group finally took off for Leron. King flew in the lead plane, which was piloted by Captain Frank C. Church, whom Kenney described as "one of Hutchison's 'hottest' troop carrier pilots". As it came in to land, King spotted patrols from the Papuan Infantry Battalion in the area. One of the Dakotas blew a tyre touching down on the rough airstrip; another tried to land on one wheel. Its undercarriage collapsed and it made a
belly landing. The former was subsequently salvaged, but the latter was a total loss. King sent out patrols that soon located Captain
J. A. Chalk's B Company, Papuan Infantry Battalion, which was operating in the area. That evening Chalk and King received airdropped messages from Vasey instructing them to occupy Kaiapit as soon as possible, and prepare a landing strip for troop-carrying aircraft. Vasey informed them that only small Japanese parties that had escaped from Lae were in the area, and their morale was very low. Vasey flew in to Leron on 18 September to meet with King. Vasey's orders were simple: "Go to Kaiapit quickly, clean up the Japs and inform division." As it happened, the Japanese commander, Major General
Masutaro Nakai of the
20th Division, had ordered a sizeable force to move to Kaiapit under the command of Major Yonekura Tsuneo. Yonekura's force included the 9th and 10th Companies of the
78th Infantry Regiment, the 5th Company of the
80th Infantry Regiment, a heavy machine-gun section, a signals section and an engineer company—a total of about 500 troops. From Kaiapit it was to threaten the Allied position at Nadzab, creating a diversion to allow the Japanese garrison at Lae time to escape. The main body left Yokopi in the
Finisterre Range on 6 September but was delayed by heavy rains that forced the troops to move, soaking wet, through muddy water for much of the way. Only the advance party of this force had reached Kaiapit by 18 September, by which time Lae had already fallen. Yonekura's main body, moving by night to avoid being sighted by Allied aircraft, was by this time no further from Kaiapit than King, but had two rivers to cross. Since both were heading for the same objective, a clash was inevitable. == Battle ==