Fire controlman Fire controlman ( abbreviated as FC ) is a United States Navy occupational rating . Fire controlmen provide system employment recommendations ; perform organizational and intermediate maintenance on digital computer equipment , subsystems , and systems ; operate and maintain combat and weapons direction systems , surface - to - air and surface - to - surface missile systems , and gun fire control system s at the organizational and intermediate level ; inspect , test , align , and repair micro / minicomputers and associated peripheral equipment , data conversion units , data display equipment , data link terminal equipment , print devices , and system related equipment ; make analysis for detailed systems , computer programs , electronics , and electronic casualty control ; and operate associated built - in and external test equipment ; load , initialize , and run preprogrammed diagnostic , performance and testing routines for digital computer equipment , digital subsystems , digital systems , and overall combat systems . FCs attend ATT ( Apprentice Technical Training ) and " A " - School at Naval Station Great Lakes ; this course is roughly eight months long followed then by a " C " - school , based on one of the systems described below , which varies in length from 4 months to 8 months . FCs typically operate weapon systems on - board surface combatant ships . They are trained in the repair , maintenance , operation and employment of weapons such as the Tomahawk Missile System , the Close - In Weapons System , the 5 " / 54 caliber Mark 45 gun weapon system and its associated MK86 or MK160 Gun Fire Control System , the MK92 Gun Fire Control System ( on Frigates ) the Sea Sparrow missile system , and the Harpoon Missile Systems . These include their associated computer and sensor packages . Their job is somewhat unique in that they are trained to troubleshoot and repair their systems , as well as operate them . These responsibilities are typically split up between different ratings for various types of electronic equipment . In essence , they " pull the trigger " , to defend the ship from tactical threats , or to make an offensive strike against a hostile target . Another area of responsibility for FCs is the Aegis weapon system , which includes one of the most powerful air - search radars , deployed at sea , in the world , the SPY - 1 , as well the MK99 Fire Control System , used for terminal guidance of Standard Missiles , and the Aegis Computer Suite . The Origin . The rating was established in 1941 . It was split off of the gunner ' s mate rating . Fire controlman were highly skilled sailors responsible for the operation of various forms of range finding gear , and solving ballistic calculations to control the firing of the ship ' s guns . These skills were originally employed primarily for naval gunfire support , and surface combat , but today fire controlman also play an extensive role in air warfare as well . The fire controlman rating was later renamed " fire control technician " ( FT ) , with specific sub - designators for gunnery ( FTG ) , missiles ( FTM ) and submarines ( FTS ) . In 1985 the name of this naval rating has changed back to fire controlman . This allowed for the separation of the submarine rate FT from surface rate FT to FC . FC was the original name of the rate through WWII when optic devices called theodolite s were used . After WWII , when the duties changed to more technical things like radar and computers , the name was changed to fire control technician ( FT ) . The FT name is now used exclusively for fire control personnel on submarines . The rating insignia is an coincidence or stereoscopic rangefinder , with two lightning bolts ( called " sparks " ) signifying the technical side . Until 1985 it had always been just the rangefinder without the lightning bolts . FCs maintain the control systems used in aiming and firing weapons on all equipped ships . Complex computers , electronics , electrical , and hydraulic equipment is required to ensure the accuracy of guided missile and surface gunfire control systems . FCs are responsible for the operation , routine care , and repair of this equipment , which includes radars , computers , weapons - direction equipment , target - designation systems , gyroscopes , and rangefinders . The fire controlmans creed . I am a Fire Controlman , A Petty Officer of the United States Navy , my work is the operation and maintenance of the weapons aboard the fighting ships of the Navy , I am required to know , operate , and maintain intricate scientific precision instruments . < br > To do this , I must have a thorough knowledge of the work of an Electronics Technician , Machinist Mate , Gunners Mate , Machinery Repairman , Operations Specialist , and Engineman . < br > My aim in life is to know my job ; to know everything that pertains to practical gunnery and ordnance . < br > As long as there is any operation or piece of equipment I do not fully understand , my job is not complete . < br > In the event of war , I must be prepared for any emergency . < br > I must be capable of and competent to fill my station , or perform any operation in the weapons department of my ship ; to assume command of , spot , or control the fire of any battery . < br > In addition to being competent to perform any operation , I will strive to know my maintenance duties so well that I may maintain the battle efficiency of my ship , even on a darkened ship , under enemy fire . This to the end … THAT THE SHIP MAY FIGHT AS LONG AS SHE IS AFLOAT !