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
Group captain air forces, such as Colonel, other air services, especially non-combat auxiliaries in Commonwealth countries, have used a variety of alternative names for equivalent ranks. The equivalent rank in the Women's Auxiliary Air Force, Women's Auxiliary Australian Air Force, Women's Royal Air Force (until 1968) and Princess Mary's Royal Air Force Nursing Service (until 1980) was "group officer". The equivalent rank in the Royal Observer Corps (until 1995) was "observer captain", which had a similar rank insignia. Group captain Group captain is a senior commissioned rank in many air forces. Group captain has a NATO rank code of OF-5, meaning that