Squadron leader

Common military ranks in English
Navies	Armies	Air forces
Commissioned and Non-commissioned officers
Admiral of the fleet	Marshal or Field marshal	Marshal of the air force
Admiral	General	Air chief marshal
Vice admiral	Lieutenant general	Air marshal
Rear admiral	Major general	Air vice-marshal
Commodore	Brigadier or Brigadier general	Air commodore
Captain	Colonel	Group captain
Commander	Lieutenant colonel	Wing commander
Lieutenant commander	Major or Commandant	Squadron leader
Lieutenant	Captain	Flight lieutenant
Sub-lieutenant	Lieutenant or First lieutenant	Flying officer
Ensign	Second lieutenant	Pilot officer
Midshipman	Officer cadet	Flight cadet
Enlisted grades
Warrant officer or Chief petty officer	Warrant officer or Sergeant major	Warrant officer
Petty officer	Sergeant	Sergeant
Leading seaman	Corporal	Corporal
Seaman	Private	Aircraftman

Squadron leader (Sqn Ldr in the RAF and PAF; 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.The air force rank of squadron leader has a NATO ranking code of OF-3, equivalent to a lieutenant-commander in the Royal Navy or a major in the British Army or the Royal Marines. The equivalent rank in the Women's Auxiliary Air Force, Women's Royal Air Force (until 1968) and Princess Mary's Royal Air Force Nursing Service (until 1980) was "squadron officer".

Squadron leader has also been used as a cavalry command appointment (UK) and rank (France) since at least the nineteenth century. In Argentina it is used as a command appointment by both the army's cavalry and by the air force's flying units. The cavalry rank of squadron leader in France is also an OF-3 equivalent to a major, and the cavalry appointment of squadron leader in the UK generally corresponds to this rank as well.

The rank originated in the British Royal Air Force and was adopted by several other air forces which use, or used, the RAF rank system.

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