Stewart joined the Royal Air Force (RAF) as a pilot in 1969.
1 (Fighter) Squadron and went on to be Station Commander at RAF Gutersloh and to command the Harrier Field Force in Germany.
[2] He was a member of the Armed Forces Pay Review Body from 2005 to 2011.
In retirement he worked for the Defence Vetting Agency in the Gloucestershire / Herefordshire area and was Chairman of Marsden Weighing Machine Group from 2007 to November 2019.
[1] From 2017 to June 2020 he served as the Personnel Director on the Gloucestershire Warwickshire Railway.