Womersley later transferred to the Royal Flying Corps, being appointed a flying officer on 1 April 1917, and was assigned to No. 43 Squadron to fly the Sopwith 1½ Strutter two-seater fighter. On 16 June, he was part of a multi-aircraft assault on an Albatros D.III; he shared credit for the victory with his observer Air Mechanic 2nd Class J. M. O'Shea and ten squadron-mates. On 1 July 1917 he was promoted to lieutenant. Womersley gained a second victory on 23 July, driving down an Albatros D.V with his observer Second Lieutenant Cyril Agelasto. His squadron was then re-equipped with the single-seater Sopwith Camel; in which he gained two more victories on 24 October. His fifth and final victory came on 12 November 1917. That same day, he crashed during a practice flight and was severely injured.
