Jackson was awarded the Distinguished Flying Cross and Mentioned in Despatches for his actions in the Middle East. In March 1942, while serving in the South West Pacific theatre, he was promoted to squadron leader. He was in command of No. 75 Squadron at Port Moresby in Papua, operating P-40 Kittyhawks. Described as "rugged, simple" and "true as steel", Jackson, aged 34, was nicknamed "Old John" by his much younger squadron members. He was praised for his leadership during the defence of Port Moresby. He was killed in action on 28 April 1942. His younger brother Les took over No. 75 Squadron, and also became a fighter ace. Jacksons International Airport, Port Moresby, is named in John Jackson's honour.