The attack took place on the night of 10/11 August 1944 and involved attempts to bomb an oil refinery at Palembang and lay mines to interdict the Musi River.

The raid formed part of a series of attacks on Japanese-occupied cities in South East Asia that XX Bomber Command conducted as an adjunct to its primary mission of bombing Japan.

Fifty-four Boeing B-29 Superfortress heavy bombers were dispatched from an airfield in British Ceylon on 10 August, of which 39 reached the Palembang area.

The Japanese antiaircraft guns and fighter aircraft assigned to defend Palembang failed to destroy any of the American bombers, but one B-29 ditched when it ran out of fuel.

At the time of the Pacific War, the Sumatran city of Palembang in the Dutch East Indies was a major oil production center.

[2] In late 1943, the United States Joint Chiefs of Staff approved a proposal to begin the strategic air campaign against the Japanese home islands and East Asia by basing B-29 Superfortress heavy bombers in India and establishing forward airfields in China.

The main element of this strategy, designated Operation Matterhorn, was to construct airstrips near Chengdu in inland China which would be used to refuel B-29s traveling from bases in Bengal en route to targets in Japan.

During late 1943 and early 1944, serious consideration was given to initially using the B-29s to attack merchant shipping and oil facilities in South East Asia from bases in northern Australia and New Guinea.

[6] The final plan for Operation Matterhorn approved by the Joint Chiefs of Staff in April specified that while XX Bomber Command would focus on Japan, it was to also attack Palembang.

[7] The inclusion of Palembang in the plan represented a compromise between the strategists who wanted to concentrate the force against Japan and those who wished to focus it on oil targets.

[10] Saunders decided to delay the attack on Palembang until mid-August to enable XX Bomber Command to first make a maximum effort raid on Anshan in China, which Arnold had accorded the highest priority.

[2] Due to the very long distance which was to be flown and the need to stage through Ceylon, the operation required more planning and preparations than any of the other raids conducted by XX Bomber Command.

The Twentieth Air Force initially ordered that the attack involve all 112 of XX Bomber Command's aircraft, and be conducted during the day.

The command sought to have this directive modified on the grounds that dispatching so many aircraft from a single airfield would mean that the force would need to be separated into several waves.

XX Bomber Command staff wanted to cancel the mission, which they viewed as a distraction from the main effort against the Japanese steel industry.

The Joint Chiefs of Staff continued to require that Palembang be attacked, and Arnold included it in another target directive issued in July.

Part of the force was tasked with dropping naval mines to interdict the Musi through which all the oil produced at Palembang was shipped.

[16] An attack by XX Bomber Command on the Japanese city of Nagasaki was scheduled to take place on the same night as the raid on Palembang.

While one of the aircraft returned to the base 40 minutes after taking off due to engine problems, it was repaired within two hours, and took off again bound for Sumatra.

Royal Navy vessels involved included the light cruiser HMS Ceylon, destroyer Redoubt and submarines Terrapin and Trenchant.

[15] Eight B-29s descended below the clouds to drop two mines each in the Musi River; the accuracy of this attack was assessed as "excellent" in a post-attack report.

[16] The mine-laying element of the attack was successful: three ships totalling 1,768 tons were sunk, four others were damaged and the Japanese were unable to transport oil via the Musi River for a month until minesweeping was complete.

[29] The command continued to be reluctant to attack Palembang and recommended to the Twentieth Air Force on 24 August that its facilities at China Bay be abandoned.

[16] XX Bomber Command attacked several other cities in South East Asia during 1944 and early 1945; these included multiple raids on Japanese-occupied Singapore which required even longer flights than those to reach Palembang.

The Japanese general who commanded the oil refineries at Palembang stated after the war that these attacks had inflicted much more damage than Operation Boomerang.