14 B-17 Flying Fortresses that survived the Battle of the Philippines left Mindanao for Darwin, Australia, between 17 and 20 December 1941, the only aircraft of the Far East Air Force to escape. After its evacuation from the Philippines on 24 December 1941, FEAF headquarters moved to Australia and was reorganized and redesignated 5 Air Force on 5 February 1942, with most of its combat aircraft based on fields on Java. It seemed at the time that the Japanese were advancing just about everywhere. The remaining heavy bombers of the 19th Bombardment Group, based at Malang on Java, flew missions against the Japanese in an attempt to stop their advance. They were joined in January and February, two or three at a time, by 37 B-17Es and 12 LB-30s of the 7th Bombardment Group. The small force of bombers, never numbering more than 20 operational at any time, could do little to prevent the invasion of the Netherlands East Indies, launching valiant but futile attacks against the masses of Japanese shipping, with six lost in combat, six in accidents, and 26 destroyed on the ground.

The 7th Bombardment Group was withdrawn to India in March 1942, leaving the 19th to carry on as the only B-17 Fortress-equipped group in the South Pacific. About this time it was decided that replacement B-17s would not be sent to the southwest Pacific, but be sent exclusively to the Eighth Air Force which was building up in England. By May, 5 Air Force's surviving personnel and aircraft were detached to other commands and the headquarters remained unmanned for several months, but elements played a small part in the Battle of the Coral Sea (7–8 May 1942) when the 435th Bomb Squadron of the 19th Bomb Group saw the Japanese fleet gathering in Rabaul area nearly two weeks before the battle actually took place. Because of the reconnaissance activity of the 435th Bomb Squadron, the US Navy was prepared to cope adequately with the situation. The squadron was commended by the US Navy for its valuable assistance not only for its excellent reconnaissance work but for the part played in the battle.

Headquarters Fifth Air Force was re-staffed at Brisbane, Australia on 18 September 1942 and placed under the command of Major General George Kenney. United States Army Air Forces units in Australia, including Fifth Air Force, were eventually reinforced and re-organised following their initial defeats in the Philippines and the East Indies. At the time that Kenney had arrived, Fifth Air Force was equipped with three fighter groups and five bombardment groups.

65mm Woven Patch