My time in the Navy was spent as a Firecontrolman (FC). Contrary to what most people assumed that meant, I was not a fireman, and did not put out, or control fires. If anything, I guess I was more likely to start one!
A firecontrolman is a highly trained electronics technician that is responsible for the maintenance, testing, and operation of the equipment that controls and directs naval weapons. For those of you who served in the Navy before me, this job, or "rating", used to be called Firecontrol Technician, or "FT". Right before I enlisted, the Navy combined Firecontrol Technician - Guns (FTG), and Firecontrol Technician - Missiles (FTM), into a combined rate - Firecontrolman. FTG's were used in the submarine service.
As an enlisted person in the Navy, you generally have to "test" to advance in rank. Your test score is combined with other numbers into what's called a "final multiple". If your multiple is higher than the magic number, you advance. I swear, they used to just make those numbers up! The bad thing about the firecontrol rates being combined is that you were tested on both gun systems AND missile systems, even though you were usually only formally trained on one or the other.
The weapon system that I was trained on was the Phalanx Close-In Weapon System (see photo below, circa 1990), or by the acronym "CIWS". It was an awesome weapon that was a computer controlled, radar guided, six barrelled Gatling type gun. It fired a slug that was 2.5 times denser than steel, at a velocity of about 3,500 feet per second, and a rate of 50 rounds per second! The Phalanx was designed as a defensive weapon only, to protect the ship from incoming cruise missiles. It did not miss! Okay, if the first 3 or 4 rounds missed, the few hundred that were right behind them got the job done!