Royal Air Force Volunteer Reserve
The Royal Air Force Volunteer Reserve (RAFVR) was established in 1936 to support the preparedness of the U.K. Royal Air Force (RAF) in the event of another war. The Air Ministry intended it to form a supplement to the Royal Auxiliary Air Force (RAuxAF), the active reserve for the RAF, by providing an additional non-active reserve.
Source: Wikipedia — Royal Air Force Volunteer Reserve (CC BY-SA 4.0)