John Shannon enlisted in the Royal Australian Air Force (RAAF) in February 1943, aged 18. He undertook initial training as a pilot in Tiger Moth and Oxford aircraft in Australia before leaving for the United Kingdom in April 1944.
In December 1944, John was posted to RAF Base Waddington, home of Nos 463 and 467 RAAF Bomber Squadrons. Although he qualified as a pilot, John served as an Air Traffic Controller due to a surplus of pilots, which was point of disappointment to him. He had wanted to fight and was denied the chance to prove to himself whether he had the 'guts to go on' when it came to 'the real crunch'.
John recalled with some bitterness the seemingly incessant delays that dogged his training and posting overseas, which he said cost him the opportunity to fly combat missions. Reflecting on the boys with whom he went through school who died in service, he said he carried with him a deeply personal memory of their loss.
Returning to Australia in November 1945, John discharged from the RAAF in January 1946. He joined the Commonwealth Public Service and worked for the Department of Immigration for 40 years. In that period, he was posted to London from 1952 to 1958, and was involved in promoting the assisted passage scheme.
John remained active in the ex-service community as an Honorary Life Member of the Sergeants' Mess at East Sale RAAF base, his main social outlet until his passing in 2015.