He graduated with a PhD from Sheffield University in 1934, and (as a Commonwealth Fund Fellow) an MS from Illinois in 1936, where he studied impact stresses in beams.
[1] His war service, from 1939 to 1945, was conducted in the Research Department of the Metropolitan-Vickers Electrical Company.
Finally, he was appointed Regius Professor of Engineering in the University of Edinburgh in 1946, a position he retained until his death in 1963.
At Edinburgh, he instituted two postgraduate schools, one in electronics and radio (1950), the other in applied dynamics (1957).
[3] Arnold died on 30 December 1963, survived by his widow, Jessie Beattie Blake, and a son.