The man ultimately in charge of RAF missing research was the Air Member for Personnel, the AMP, the equivalent of the Army’s Adjutant-General. Beneath him came the Directorate of Personal Services, the DPS, and beneath this came the Air Ministry Casualty Branch, whose Missing Research and Enquiry Service, the MRES, operated in the field after the liberation of Europe. It was the MRES which, in liaison with the Army Directorate of Graves Registration and Enquiries, conducted all the post-liberation and post-war fieldwork of identifying the RAF missing in Europe.
At the outset of the war in September 1939, the resources devoted to missing research were inadequate to deal with what soon proved to be the rapidly escalating nature of RAF losses. Thereafter, resources were increased after a series of crisis points when existing staff could no longer cope with the heavy workload.
The most significant change came in January 1942 when the Missing Research Section (MRS) of the Casualty Branch was formed to deal with this aspect of RAF casualties. The MRS was confined to offices in Britain until after the invasion of Italy in September 1943 and of France in June 1944.
Under its new name, the Missing Research and Enquiry Service, the MRES worked in the field in newly liberated Europe. There was a massive increase in MRES resources in the summer of 1945 when it became obvious that this was the only way that the search would be completed within a reasonable timescale.