P/O Smith joined the RAF with a direct-entry commission on 1st June 1940 and went to 24 (Communications) Squadron at Hendon.

Denis arrived at 6 OTU Sutton Bridge on 22nd June 1940 and after converting to Spitfires he was posted to join the Tigers at Hornchurch on 20th July.
On 11th of August, 1940, he failed to return from combat just after midday when protecting Convoy Booty thirty miles off Clacton. His aircraft (R6962) was jumped by Me 110s and 109s. No Air Sea Rescue vessel was at hand and his body was eventually taken from the sea by the Germans.
26 years old, Denis Smith was buried in Oostende`s New Communal. Cemetery (with Harold Gunn & Don Cobden)