from Tarakan on the night of 29/30 April and landed on the mainland of Borneo. They were unable to transmit the intelligence they had collected, however, as their radio set malfunctioned. Members of the party eventually landed within the Allied beachhead on Tarakan on 3 May to report to the 26th Brigade, but Whitehead was disappointed with the results of this operation and made no further use of the SRD during the battle. Prelude Opposing forces Allies The Allied force responsible for capturing Tarakan was centred around the very experienced Australian 26th Brigade Group of nearly 12,000 soldiers. The 26th Brigade had been formed in 1940 and had seen action in North Africa and New Guinea. The brigade's infantry component was the 2/23rd, 2/24th and 2/48th Battalions, also with much war experience. These battalions were joined by the 2/4th Commando Squadron and the 2/3rd Pioneer Battalion, which fought as infantry in this battle. The brigade group also included the 2/7th Field Regiment equipped with 24 25-pounder guns, a squadron from the 2/9th Armoured Regiment operating 18 Matilda tanks, a company of the 2/2nd Machine Gun Battalion, the 53rd Composite Anti-Aircraft Regiment and two engineer field squadrons. These combat units were supported by a large number of logistics and medical units, including the 2nd Beach Group whose role was to land supplies from the invasion fleet. While the 26th Brigade Group greatly outnumbered the known strength of Tarakan's Japanese defenders, the Allies committed this large force as their previous experience indicated that it would be difficult to defeat the Japanese force if it retreated into Tarakan's rugged interior. The 26th Brigade Group was supported by Allied air and naval units. The air units were drawn from the Australian First Tactical Air Force (1 TAF) and United States Thirteenth Air Force and included fighter and bomber squadrons. The naval force was drawn from the United States Seventh Fleet and included several Royal Australian Navy warships and transports. Since the main objective of attacking Tarakan was to use the island's airstrip, the invasion force also included a large number of Royal Australian Air Force ground units, including No. 61 Airfield Construction Wing comprising No. 1 and No. 8 Airfield Construction Squadrons. The force which landed on Tarakan included nearly a thousand United States and Dutch troops. The U.S. troops included the U.S. Army engineers who manned the invasion force's LCMs and LCVPs and