Starfleet Rank Index: Officer
Ranks in Starfleet follow a specific order, and are of three types: Flag Officer, Officer, and Enlisted. Enlisted crewmen are not trained in any command fields, and fulfill the mundane duties of a starship. Officers are trained for command, and it is assumed that some will someday reach the ranks of captain or above. Flag officers often fulfill administrative duties, and sometimes command task forces of ships. Promotions are awarded for quality of service, not for length of time served.
Captains are the most senior of line officers. Captains most often command Starships or Starbases of medium to large size. Captains may also command planetary outposts or serve as division heads for the Starfleet Bases on major worlds.
Commanders are senior line officers. Commanders usually serve as the Executive Officer, Operations Officer, or Security Chief onboard a starship. Commanders may command small starships of under 100 crewmen, but this is rare. Commanders may also command small Starbases or minor outposts. Taking the Bridge Officer's Test is the only way for a science or medical officer to be promoted to Commander, pending completion of the other requirements
Lieutenant Commanders are senior line officers. Lieutenant Commanders usually serve as department heads aboard starship or on large Starbases. Lieutenant Commanders may be the executive officers on starships with a crew of less than 250, but usually Commanders fill that role.
Lieutenants are the most common Commissioned Officers. Lieutenants can perform almost any Officer duty on a starship, save for being the Commanding or Executive Officer. In some cases Lieutenants can even be department heads, especially on smaller starships.
Lieutenant Junior Grade
Lieutenants Junior Grade are junior Commissioned Officers. Lieutenants Junior Grade may be the Medical Officer or Science Officer on a mid to large space station, or man a Bridge Station. Officers typically spend around 2 years as a Lieutenant Junior Grade.
Ensigns are the most junior of Commissioned Officers. Ensigns often serve as Flight Controller aboard starships, or Operations Officer on small Starships. Ensigns can also serve in relief or assistant capacities to most other positions aboard ship. It is rare, but not unheard of, for a Cadet at Starfleet Academy to be granted a temporary Commission of Ensign. This is only done in cases of truly outstanding grades. Officers typically spend around 3 years as an Ensign.
Cadet 1st Class
Cadets 1st Class are cadets in their final year at Starfleet Academy. They have a leadership role in the Cadet Corps. Cadet's 1st Class usually have at least 1 training cruise behind them and have earned at least 90 academic credits. A Cadet 1st Class may lead a Cadet Flight Squadron or special Cadet Operations Squad.
Cadet 2nd Class
Cadets 2nd Class are cadets in their third year. In their third year at the Academy, cadets undergo advanced training in their field as well as detailed instruction on the current state of the Galaxy. Cadets 2nd Class may elect to take a training cruise in place of a class in Starfleet Operations. These cruises last between 4 and 16 weeks and give Cadets real space experience.
Cadet 3rd Class
Cadets 3rd Class are cadets in their second year. In their second year at the Academy, cadets participate in field duty. A Cadet may be posted in a training role to a Starship or Starbase, or may be lucky enough to earn membership in a Cadet Squadron or Cadet Operations Squad.
Cadet 4th Class
Cadets 4th Class are the lowest level of Cadet. They are 1st year students with no seniority or special privileges. Cadet's 4th Class undergo what are certainly the worst conditions in Starfleet. Cadet's 4th class endure cramped Barracks, very intensive physical conditioning, and difficult classes. The ordeal almost always produces a hardworking, dedicated cadet.
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