With the 4th Battalion, Royal Irish Regiment, David Mary Tidmarsh was promoted to 2nd Lieutenant (on probation) on 23 April 1915. He received Royal Aero Club Aviator's Certificate 1833 on a Maurice Farman biplane at Military School, Ruislip on 7 October 1915. He transferred to the Royal Flying Corps on 13 January 1916 and was posted to 24 Squadron under Lanoe Hawker. On 21 April 1916, he narrowly escaped death when an unexploded anti-aircraft shell passed through the cockpit of his D.H.2. With the formation of 48 Squadron in 1917, Tidmarsh became a flight commander in the first squadron to fly the Bristol Fighter in combat. On 11 April 1917, after downing two Albatros D.III aircraft, Tidmarsh was captured when he was shot down by Kurt Wolff of Jasta 11. He was repatriated on 30 December 1918.
Great Britain, Royal Aero Club Aviators’ Certificates, 1910-1950
British Army WWI Medal Rolls Index Cards, 1914-1920
Military Cross (MC)
2nd Lt. David Mary Tidmarsh, 4th Bn., R. Ir. R. (Spec. Res.) and R.F.C.
For conspicuous gallantry and skill when attacking hostile aircraft on several occasions, notably on one occasion when he dived at an enemy machine and drove it down wrecked to the ground.