Lieutenant Commander Lieutenant Commander ( also hyphenated Lieutenant - Commander ; pronounced L ' tenant in the Royal Navy , Irish and Commonwealth navies ) is a commissioned officer rank in many navies . The rank is superior to a Lieutenant and subordinate to a Commander . The corresponding rank in most armies ( armed services ) and air force s is Major , and in the Royal Air Force and other Commonwealth air forces is Squadron Leader . The NATO rank code is OF - 3 . A Lieutenant Commander is a senior department officer on a large ship or shore installation . He or she may also be commanding officer or executive officer ( second - in - command ) of a smaller ship or installation . Origins . Lieutenants were commonly put in command of smaller vessels not warranting a Commander or Captain : such a Lieutenant was called a " Lieutenant Commanding " or " Lieutenant Commandant " in the United States Navy , and a " Lieutenant in Command " , " Lieutenant and Commander " , or " Senior Lieutenant " in the Royal Navy . The USN settled on " Lieutenant Commander " in 1862 , and made it a distinct rank ; the RN followed suit in March 1914 . United Kingdom . Royal Navy . The insignia worn by a Royal Navy Lieutenant - Commander ( Lt Cdr ) is two medium gold braid stripes with one thin gold stripe running in between , placed upon a navy blue / black background . The top stripe has the ubiquitous loop used in all RN officer rank insignia . The RAF follows this pattern with its equivalent rank of Squadron Leader . Having fewer officer ranks than the army , the RN previously split some of its ranks by seniority ( time in rank ) to provide equivalence : hence a Lieutenant with fewer than eight years ' seniority wore two stripes , and ranked with an army Captain ; a Lieutenant of eight years or more wore two stripes with a thinner one in between , and ranked with a Major . This distinction was abolished when the rank of Lieutenant - Commander was introduced . Royal Observer Corps . Throughout much of its existence , the British Royal Observer Corps ( ROC ) maintained a rank of Observer Lieutenant Commander ( Obs Lt Cdr ) . The ROC wore a Royal Air Force uniform and their rank insignia appeared similar to that of an RAF Squadron Leader except that the stripes were shown entirely in black . Prior to the renaming , the rank had been known as " Observer Lieutenant ( First Class ) " . Other countries . Insignia similar to that of the Royal Navy ' s is worn by Lieutenant - Commanders in other Commonwealth navies , such as the Royal Australian Navy ( which uses the abbreviation " LCDR " ) , the Royal New Zealand Navy , the Irish Naval Service , and the Canadian Forces Maritime Command ( formerly known as the Royal Canadian Navy , and which uses the abbreviation " LCdr " ) . Unlike the United States Navy , personnel in the Royal Navy and other Commonwealth navies addressing a Lieutenant - Commander do not abbreviate the rank to " Commander " . The United States Navy always addresses officers using the higher grade of the rank ; as an example , a LTJG is not referred to as Lieutenant Junior Grade , but simply as Lieutenant , and a Lieutenant Commander is referred to as a Commander . If either a Commander or Lieutenant Commander have screened for and are in command of a naval vessel or installation , they are called captain , as the commanding officer of any warship is entitled to be , regardless of rank , and casually referred to as the skipper . The corresponding rank in the German Navy , Italian Navy , French Navy , Spanish Navy and most French and Spanish - speaking countries is " Corvette Captain " . The corresponding rank in the Portuguese Navy is " Lieutenant Captain " , while the Brazilian Navy uses " Corvette Captain " . The corresponding rank in the Polish Navy is " Komandor podporucznik " . Russia . The corresponding rank to Lieutenant Commander is Captain 3rd Rank .