The Battle of Port Moresby was an aerial battle fought between the

Royal Australian Air Force The Royal Australian Air Force (RAAF) is the principal Air force, aerial warfare force of Australia, a part of the Australian Defence Force (ADF) along with the Royal Australian Navy and the Australian Army. Constitutionally the Governor-Gener ...

(RAAF) and

United States Army Air Force The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and ''de facto'' aerial warfare service branch of the United States during and immediately after World War II ...

(USAAF) on one side and the

Imperial Japanese Army The Imperial Japanese Army (IJA; , ''Dai-Nippon Teikoku Rikugun'', "Army of the Greater Japanese Empire") was the principal ground force of the Empire of Japan from 1871 to 1945. It played a central role in Japan’s rapid modernization during th ...

and

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, Potsdam Declaration, when it was dissolved followin ...

on the other between 3 February 1942 and 17 August 1943 over

Port Moresby (; Tok Pisin: ''Pot Mosbi''), also referred to as Pom City or simply Moresby, is the capital and largest city of Papua New Guinea. It is one of the largest cities in the southwestern Pacific (along with Jayapura) outside of Australia and New ...

, Papua. At the start, the defenders consisted only of Australian Army anti-aircraft batteries and machine-guns, but by late March had been strengthened by the arrival of Kittyhawk fighters from No. 75 Squadron RAAF. However, in just nine days they lost 11 aircraft and only the arrival of replacements enabled the unit to maintain ten serviceable machines. According to the Australian government:

On 31 March, the Australians were joined by the American 8th Bombardment Squadron with A-24 bombers and for two weeks in May by six P-39 Airacobras of the American 36th Pursuit Squadron. Despite the American assistance, the daily air battles over and around Port Moresby by 1 May had reduced No. 75 Squadron RAAF to just three airworthy machines. The American 35th, and the full 36th, Pursuit Squadrons arrived to relieve the Australian squadron. During their time in Port Moresby 75 Squadron had lost 21 aircraft and 12 pilots. The
Battle of the Coral Sea The Battle of the Coral Sea, from 4 to 8 May 1942, was a major naval battle between the Imperial Japanese Navy (IJN) and naval and air forces of the United States and Australia. Taking place in the Pacific Theatre of World War II, the battle ...
, which was fought mostly in the waters south-east of Papua in early May, diverted a Japanese naval attack against Port Moresby and removed the immediate threat. However, by May 1942 the Japanese had established themselves in the arc of islands north and east of the island of New Guinea as well as in the region around Lae and Madang on the north coast of the mainland.

References

Defense of Port Moresby

Pathfinder Issue 103 January 2009
''Retrieved on 20 June 2009''.
Chapter 3: Japanese Air Operations over New Guinea
''Retrieved on 20 June 2009''. Conflicts in 1942 1942 in Papua New Guinea 1942 in aviation World War II aerial operations and battles of the Pacific theatre

Battles and operations of World War II involving Papua New Guinea {{mil-aviation-stub