A Star Fleet vessel is designated by class, a name, and a hull number. The class is a of a ship designates its function and purpose. For example, the USS Czar Alexander IV is designated DDG, and has hull number NCC-571. The DD means destroyer, the G means that it carries guided drones. There may be differences between ships of the same class, but they are considered minor in terms of functionality. The class and name are generally used in official documents rather than the hull number.
The workhorse of Star Fleet, used in both defense and internal projects. It was originally ommisioned in Y127 as the Constellation class, but a revision of the design resulted in the Constitution class after only 3 originals. In combat, this ship relies on toughness and on a flexible use of power. It has an abundance of labs and other support facilities as well as more spacious quarters than most. In all, the envy of the rest of the fleet.
There are currently 22 of these ships in the fleet, including the reknown Enterprise, which is currently being refitted to incorporate improvements in the design. The power systems and shields will be enhanced, and additional phasers banks will be added, along with a drone rack. The refitted cruiser will be designated ``CA+''. 5 of these ships are currently inactive (`mothballed' to reduce fleet maintenance costs).
The command cruiser is an improved variant of the standard heavy cruiser, noted for its firepower and versatility. There are currently 6 of these ships in the fleet, two of which are currently undergoing upgrades similar to the Enterprise.
The CL is a rebuilt hull that is over 100 years old, dating back to the first Terran warp vessel, before there even was a Star Fleet. The Texas class dates to the first use of dilithium moderated drives; it was refitted to incorporate later improvements. The old hull is equipped with superconducting armor, which was used before the more powerful deflector shields were developed. This ship has a good operating speed and excellent reserve power, but it is vulnerable to penetrating damage.
It formed the backbone of Star Fleet for two decades, before enough heavy cruisers came into service to assume that role. There are currently 27 of these ships in the fleet, 12 of which are inactive. Two have been rebuilt as Survey Cruisers, and are designated ``CLS''. One is now a specialized commando cruiser, designated ``CMC''.
The destroyer was designed as a smaller and less expensive stablemate to the CA, but was less successful. While it carries cruiser armament, it lacks the engine power of a cruiser, making full use of its photon torpedoes impractical. While lacking maneuverability, its large saucer section makes it capable of taking considerable punishment without losing warp power.
The Federation destroyer was expected, during peacetime, to carry out essentially the same research and exploration missions as the heavy cruiser class. For this reason, it had the same laboratory facilities. There are currently 18 of these ships in the fleet.
Five years ago, 6 of these ships were reactivated and brought to the Klingon border, and they remain active, taking over tasks previously performed by frigates.
Built on a destroyer hull, the scout was designed to be the electronic eyes and ears of the fleet. The name can be confusing. The ship does not actually move ahead of the fleet, but uses its long range sensors and scanners to search farther than other ships can. There are currently 6 of these ships in the fleet.
Used by Star Fleet to transport priority military and government cargoes (civilian freighters being adequate for other loads), the tug is a full-fledged starship with limited armament suitable to its position. There are currently 7 of these ships in the fleet.
The Galactic Survey Cruiser is intended for long-range research and reconnauissance missions into uncharted regions. It has more labs and shuttles than the cruisers, and in addition has considerable cargo storage space. There are currently 3 of these ships in the fleet.
A contemporary of the cruiser and destroyer designs, the frigate has a good forward firepower but has (like most Federation ships) poor weapon arcs in the rear. The unique long-range ability of the photon meants that Federation frigates (unlike most of those of other races) could support long-range bombardments.
The frigate is useful in many patrol and escort roles, but is considered undergunned for wartime. Starting 4 years ago, these ships began refits, which improved the power and shields, and added a drone rack. There are currently 42 of these ships in the fleet. 26 of these have been refitted, and 4 more will be, while the other 12 are being mothballed to reduce maintanence costs. The refitted version has optimized power output, and an added drone rack. It is designated ``FFG''.
The police cutter (sometimes referred to as a police cruiser) is intended for customs regulation, space rescue, and law enforcement. It is not intended to stand up in combat to warships. Its design predates the Orion CR, which clearly outmatches it. When heavy pirate units are expected, these ships operate in groups of three or call for the nearest Star Fleet cruiser.