In April 1918 it was decided to form the Royal Air Force (RAF) by amalgamating the Royal Naval Air Service (RNAS) with the Royal Flying Corps (RFC). Also formed at this time was Women's Royal Air Force (WRAF) and Sir Geoffrey Paine, the Air Ministry Master General of Personnel, appointed Gertrude Crawford as its first commandant. However, Lady Crawford soon discovered she was expected to be little more than a figurehead and that Lieutenant-Colonel Bersey, was actually running the service. Unhappy with this situation, Lady Crawford decided to resign from the post.
Sir Geoffrey Paine now asked Douglas-Pennant to become commander of the Women's Royal Air Force. It was not long before Douglas-Pennant got the impression that the Royal Air Force was not fully committed to the WRAF . She was given no secretarial help and had difficulty getting the use of a staff car for official journeys. Douglas-Pennant resigned but agreed to go back after being promised that her complaints would be dealt with.
Sir William Weir, Secretary of State for Air, asked Lady Margaret Rhondda, Director of of Women's Department of the Ministry of National Service, to report on the state of the WRAF. Rhondda's report was highly critical of Douglas-Pennant, and Weir decided to dismiss her as Commandant of the WRAF and replace her with Helen Gwynne-Vaughan, Overseas Commander of the Women's Army Auxiliary Corps (WAAC).
Over the next nine month 9,000 women were recruited into the Women's Royal Air Force to work as clerks, fitters, drivers, cooks and storekeepers. Gwynne-Vaughan was a great success as commander of the organisation. Sir Sefton Brancker argued that "the WRAF was the best disciplined and best turned-out women's organization in the country." Gwynne-Vaughan's work was recognised in June, 1919, when she was awarded the Dame Commander of the Order of the British Empire (DBE). However, after the war it was decided to disband the WRAF and Helen Gwynne-Vaughan left office in December, 1919.
Gwynne-Vaughan helped to form the WRAF Old Comrades Association and became its first president in March 1920. Ten years later, on the instigation of Helen Gwynne-Vaughan, the association added a new objective to its rules. This stated that the organisation should "encourage preparedness to help the country in time of need."
With war with Germany looking inevitable in the summer of 1939, Helen Gwynne-Vaughan was asked to become head of the recently established Women's Auxiliary Air Force (WAAF). As she was now sixty she declined the offer and instead suggested Jane Trefusis-Forbes, the Director of the Auxiliary Territorial Services (ATS). Trefusis-Forbes was appointed commander of the WAAF on 28th June, 1939.