Smith was commissioned as a temporary
second lieutenant in the
Gordon Highlanders on 10 September 1915. He was serving in the 2nd Battalion, which formed part of the
20th Brigade,
7th Division, when it was sent to serve in Italy in November 1917. On 3 July 1918
No. 139 Squadron RAF was formed at
Villaverla as a fighter-reconnaissance squadron equipped with the
Bristol F.2 two-seater fighter. The day after, 4 July, with the American Lieutenant
Walter Carl Simon as his pilot, Smith drove down out of control an
Albatros D.III over
Levico. Two more victories soon followed, with Lieutenant H. C. Walters in the pilot's seat, when Smith destroyed another D.III over Cortesano on 15 July, and an
Albatros D.V over Nemo on 17 July. On 30 July, Smith was flying with Lieutenant Simon again, and was with his squadron on an offensive patrol when it encountered a squadron of 16 enemy aircraft. In the ensuing dogfight Simon and Smith were credited with five enemy aircraft destroyed within five minutes, though both men were wounded and their aircraft badly damaged. ==Post-war career==