Percival Ewart Appleby was the son of Jabez and Minnie Elizabeth (Daken) Appleby. A draftsman from Nova Scotia, he enlisted in the Canadian Overseas Expeditionary Force on 25 September 1914. On 27 January 1918, he transferred to the Royal Flying Corps. Appleby was posted to 104 Squadron on 17 May 1918 and scored 6 victories as an observer aboard D.H.9s. Post-war, Lieutenant Appleby became an American citizen on 4 February 1935.
Distinguished Flying Cross (DFC)
Lt. (T./Capt.) Richard John Gammon.
2nd Lt. Percival Ewart Appleby.
Captain Gammon, with 2nd Lt. Appleby as Observer, was the leader of two formations (ten machines in all) on a recent raid. En route the formation was attacked by fifteen hostile aircraft; having driven these off, they reached the objective, which was successfully bombed. While thus engaged the formation was fiercely attacked by fifteen enemy machines, which continued the attack for some distance on the return journey, until they were driven off. Upon nearing our lines the formation was again assailed by seven machines; in the engagement that ensued one of these was destroyed and two driven down by Captain Gammon and his Observer, and, in addition, three others were destroyed by our other machines. The officer who led the whole of the combined formations of this raid speaks in the highest terms of Captain Gammon's leadership and skilful co-operation. 2nd Lt. Appleby was of the greatest assistance to Captain Gammon throughout, keeping him informed of the movements and manoeuvres of the hostile machines. This officer has taken part in numerous raids, displaying on all occasions great keenness and determination.
Supplement to the London Gazette, 2 November 1918 (30989/12976)