The son of Lt. Col. Arthur Hugh and Helen (Sheffield) Grosvenor, 2nd Lieutenant Robert Arthur Grosvenor, of the 2nd Dragoon Guards (Queen's Bays), transferred to the Royal Flying Corps in 1916 and received Royal Aero Club Aviator's Certificate 3513 on a Maurice Farman biplane at military school, Brooklands on 7 September 1916. Posted to 84 Squadron in 1917, Grosvenor scored sixteen victories flying the S.E.5a.
Appears as Robin Arthur Grosvenor in the Royal Aero Club Aviators' Certificates index.
Great Britain, Royal Aero Club Aviators' Certificates, 1910-1950
Military Cross (MC)
Lt. (T./Capt.) Robert Arthur Grosvenor, Dn. Gds., and R.A.F.
For conspicuous gallantry and devotion to duty as a leader of offensive patrols against hostile aircraft and troops on the ground. On one occasion his patrol was attacked from the rear by five enemy scouts. By skilful piloting he manoeuvred his machine into position behind one of the scouts, which he shot down in flames. He was attacked again, and drove the scout to destruction. On other occasions he has destroyed and driven down out of control at least eight hostile machines.
Supplement to the London Gazette, 26 July 1918 (30813/8804)
Military Cross (MC) Bar
Lt. (T./Capt.) Robert Arthur Grosvenor, M.C., Dgn. Gds. and R.A.F.
For conspicuous gallantry and devotion to duty in attacking enemy aircraft. He has lately destroyed two machines and driven down four others out of control. He has shown brilliant leadership and dash against heavy odds.
(M.C. gazetted 26th July, 1918.)
Supplement to the London Gazette, 16 September 1918 (30901/10891)