Gray was the son of Edward and Annabella Gray of
Edrington Castle in Mordington, Berwickshire, Scotland. He joined the
Royal Naval Air Service on 25 July 1917. By May 1918, when Gray went operational, the RNAS had been incorporated into the Royal Air Force. Gray was assigned to a former naval squadron, No. 213, as a
Sopwith Camel pilot. On 19 May 1918, Gray was patrolling with
William Pinder.
Vizefeldwebel Triebswetter of
Jasta 16 pulled away from burning a Belgian
observation balloon when the British pair shot him down. This began a run of victories for Gray that ran almost to war's end. Gray won a
Distinguished Flying Cross on 2 November 1918. He also received two belated awards in early 1919, being
Mentioned in Despatches and winning the
Croix de Guerre. and pursued a career as
aeronautical engineer. This was a long-standing interest, as he and his older brother Edward Leadbetter Gray (1897–1918) had built a primitive monoplane in 1910–1911, and a biplane in 1914–1915. On 25 October 1926 he filed a patent for his aircraft undercarriage design at the
UK Patent Office, and did the same at the
U.S. Office on 14 October 1927, being granted U.S. Patent No. 1,716,439 on 11 June 1929. In 1962 Gray, then Principal Scientific Officer at the
Royal Aircraft Establishment was made an
Officer of the Order of the British Empire in recognition of his services. ==List of aerial victories==