Chapman was born son of
Robert William Chapman and Eva Maude Chapman, née Knox, who married on 14 February 1889, and had a home on High Street,
Burnside, South Australia. He was educated at
St Peter's College and the
University of Adelaide, where he had an outstanding academic career. He enlisted with the
First AIF in August 1915, and after training at the NCO School at Mitcham served with the 12th Battalion in France, rising to rank of Captain, wounded in battle, then attached to the (British) 23rd Field Company,
Royal Engineers, Calibration Section on
Salisbury Plain. He was appointed to the South Australian Railways as a civil engineer, and in 1923 was tasked with design and building of the railway bridge at
Murray Bridge, after which he was appointed chief engineer for the State. He supervised the rebuilding of all railway bridges, station yards and locomotive depots, and the conversion of of track in the western division from narrow to
broad gauge. He supervised the construction, during World War II, of the
Finsbury munition works and the early stages of the
Salisbury munitions factory. He was made acting Railways Commissioner with the retirement of
C. B. Anderson in 1946, then appointed to the substantive position on 16 January 1947, with a contracted term of seven years. He died of a heart complaint in the (private) Ru Rua hospital a week after taking sick leave. His assistant,
J. A. Fargher, was appointed his deputy while on leave, ==Recognition==