Flight lieutenant Flight lieutenant ( Flt Lt in the RAF and IAF ; FLTLT in the RAAF and RNZAF ; formerly sometimes F / L in all services ) is a junior commissioned rank which originated in the Royal Naval Air Service and continues to be used in the Royal Air Force . The rank is also used by the air forces of many countries which have historical British influence , including many Commonwealth countries , and it is sometimes used as the English translation of an equivalent rank in countries which have a non - English air force - specific rank structure . It ranks above flying officer and immediately below squadron leader . The name of the rank is the complete phrase ; it is never shortened to " lieutenant " . In RAF informal usage , a flight lieutenant is sometimes referred to as a " flight lieuy " . It has a NATO ranking code of OF - 2 , and is equivalent to a lieutenant in the Royal Navy and a captain in the British Army and the Royal Marines . The equivalent rank in the Women ' s Auxiliary Air Force ( WAAF ) , Women ' s Royal Air Force ( WRAF ) ( until 1968 ) and Princess Mary ' s Royal Air Force Nursing Service ( PMRAFNS ) ( until 1980 ) was flight officer . Origins . On 1 April 1918 , the newly created RAF adopted its officer rank titles from the British Army , with Royal Naval Air Service lieutenants ( entitled flight lieutenants and flight commanders ) and Royal Flying Corps captains becoming captains in the RAF . In response to the proposal that the RAF should use its own rank titles , it was suggested that the RAF might use the Royal Navy ' s officer ranks , with the word " air " inserted before the naval rank title . For example , the current rank of flight lieutenant would have been " air lieutenant " . Although the Admiralty objected to this simple modification of their rank titles , it was agreed that the RAF might base many of its officer rank titles on navy officer ranks with differing pre - modifying terms . It was also suggested that RAF captains might be entitled flight - leaders . However , the rank title flight lieutenant was chosen as flights were typically commanded by RAF captains and the term flight lieutenant had been used in the Royal Naval Air Service . The rank of flight lieutenant has been used continuously since 1 August 1919 . Usage . Although in the early years of the RAF a flight lieutenant commanded an aircraft flight , it is rare that a flight lieutenant is in command of a flying unit in the modern air force . Instead , aircrew flight lieutenants are typically experienced pilots ( or weapons system officers ) without command of other personnel . However , ground flights which are administrative sub - divisions of squadrons are ordinarily commanded by flight lieutenants and these can range in size from a few specialist non - commissioned personnel to 50 or more personnel for engineering or other manpower intensive roles . In the Air Training Corps , a flight lieutenant is usually the officer commanding of a squadron . Retired flight lieutenants are the first rank that may continue to use their rank after they have left active service . Insignia . The rank insignia consists of two narrow blue bands on slightly wider black bands . This is worn on both the lower sleeves of the tunic or on the shoulders of the flight suit or the casual uniform . The rank insignia on the mess uniform is similar to the naval pattern , being two band of gold running around each cuff but without the Royal Navy ' s loop . Unlike senior RAF officers , flight lieutenants are not entitled to fly a command flag under any circumstances . Other air forces . The rank of flight lieutenant is also used in a number of the air forces in the Commonwealth , including the Bangladesh Air Force , Ghana Air Force , Indian Air Force , Pakistan Air Force , Royal Australian Air Force and Royal New Zealand Air Force . It is also used in the Egyptian Air Force , Hellenic Air Force , Royal Air Force of Oman , Royal Thai Air Force and the Air Force of Zimbabwe . The Royal Canadian Air Force used the rank until 1968 , when the three armed services were unified and army - type ranks were adopted ; flight lieutenants became captains . In official French Canadian usage , a flight lieutenant ' s rank title was " capitaine d ' aviation " . Up until the late 1970s , the Royal Malaysian Air Force used the rank . Thereafter the rank of captain was used instead .