Squadron leader Squadron leader Squadron leader (Sqn Ldr in the RAF ; SQNLDR in the RAAF and RNZAF; formerly sometimes S/L in all services) is a commissioned rank in the Royal Air Force and the air forces of many countries which have historical British influence. It is also sometimes used as the English translation of an equivalent rank in countries which have a non-English air force-specific rank structure. An air force squadron leader ranks above flight lieutenant and immediately below wing commander and it is the most junior of the senior officer ranks. The air force rank of squadron leader has a
Squadron leader RAF used major as the equivalent rank to squadron leader. Royal Naval Air Service lieutenant-commanders and Royal Flying Corps majors on 31 March 1918 became RAF majors on 1 April 1918. On 31 August 1919, the RAF rank of major was superseded by squadron leader which has remained in continuous usage ever since. Promotion to squadron leader is strictly on merit, and requires the individual to be appointed to a Career Commission, which will see them remain in the RAF until retirement or voluntary resignation. Before the Second World War, a squadron leader commanded a squadron of aircraft. Today, however,