Mobility Class
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Station
These exist only in a particular orbit around some celestial object, and as such cannot leave their location unless carried. They may have thrusters to adjust their orbit, but they are not designed to travel far. They have designation prefixes for the type of orbit, with Lunar for orbits around moons, Planetary for orbits around planets, Solar for orbits around Stars, and Interstellar for locations out in the space between stars.
Craft
These can transfer between their orbit and the object they are attached to. They can effectively move by docking to a ship. They also have the ability to land on the surface of a planet and travel through the atmosphere.
Ship
These craft possess full interstellar capabilities while also being small enough to orbit any celestial object.
Sphere
An artificial object so large that it generates its own gravity through sheer mass, a sphere ship is literally an artificial moon in terms of size and appearance. Because of this, building within a space station is not possible, and the ship must be constructed like a station. At this point, making the ship spherical is required for structural stability. The sheer mass usually allows for tremendous offensive and defensive capabilities.
Globe
Basically this is a sphere ship so large that it must be assigned a planetary orbit around a star, since it would interfere with the orbit of a planet if placed in orbit around it. Such vessels are literally moving planets of destructive potency and are terrifying sights to behold.
System
Bordering on the theoretical limits of technology, this is essentially a ship powered by a star and built around it, similar to a Dyson sphere. Such a ship is so large it must be built in galactic orbit and has the potential to wreck gravitational havoc on a system by its mere presence. Rather than entering orbit around a system, they usually function like a mobile armed artificial star system, useful for providing a staging ground for attacks or providing a zone of defence in a region of space. An even more terrifying variant is built around a cosmic black hole.
Mass Class
Also known as Level or Weight Class in common parlance, this is based on its mass or weight in metric tonnes. It is analogous to the displacement of the ship in water, and usually loosely describes the volume of space that the ship takes up, assuming the ship isn’t hollow. The use of mass-based classifications became essential as rockets depended on an accurate assessment of a ship’s mass for fuel calculations, and the cost of moving material off planet was determined in large part on the mass of the cargo. Star Cluster allows you to build any of 100 levels of ship.
Power Class
This is determined not by size, but by the ratio of weapons to defences and in the case of ships, to mobility. The unique nature of space travel means that it is not size but ratio of mass that determines how fast a ship is, and this can have enormous impact on a ship’s reach.
Stations
Fortress
A station focused on defences.
Firebase
A station built to emphasize firepower.
Craft
Shuttle
These emphasize speed and usually carry little or no armaments.
Interceptor
These are used primarily for high speed operations, and as such lack in firepower.
Fighter
These are balanced in terms of firepower and speed. They generally have minimal armour and shields, relying more on their manoeuvres to dodge attacks. They are often found on carriers as well.
Bomber
These are intended to carry much heavier armaments for use against stationary or slow moving targets, and rely less on agility and more on sheer firepower. Often they are carried by carriers to provide extra firepower. Their name is surprisingly apt, since the lack of gravity and air resistance in space allows for momentum to carry bombs against space stations as an effective and cheap way to inflict damage.
Ships
Corvette
Have the least firepower and defence, and the most speed.
Frigate
While still emphasizing speed, these ships have better defence than firepower.
Destroyer
While still emphasizing speed, these ships have better firepower than defence.
Patrol Cruiser
These ships combine strong defences and high speed, but lack firepower.
Assault Cruiser
These ships combine high firepower and speed, but lack in defences.
Battlecruiser
These ships are a well balanced mixture of firepower, defence, and speed.
Heavy Cruiser
These ships emphasize defence, and are also fairly quick, but lack in firepower.
Battledestroyer
These ships emphasize firepower and then speed, with defence being last. They are as fast as a cruiser and wield far more firepower, nearly that of a dreadnought.
Mobile Fortress
These ships are built overwhelmingly for defence, with much weaker firepower and speed.
Monitor
These ships emphasize defence and then firepower at the cost of speed.
Battleship
These ships are balanced in firepower and defence, but lack in speed.
Dreadnought
These ships emphasize firepower and then defence at the cost of speed.
Juggernaut
These ships are named after their overwhelming sheer firepower, albeit with the trade-off of negligible defence and speed. They are occasionally defined into a subtype known as a gunship, or super-gun carrier, a specially designed ship that carries a single massive supergun normally reserved for stationary defences.
Support Class
These classes involve either being unarmed, or devoting most of the space on the ship to something other than combat equipment. A ship without weapons can be classed as light, medium, or heavy based on their armour to speed ratio.
Sensor Types
If a ship is made up of a plurality of sensors, then, depending the second most common feature, the ship can be classified as:
Probe
This configuration has good speed for exploration, and to escape encounters with the enemy.
Scout
This configuration is has high defence to survive encounters with the enemy and thus be able to perform real-time surveillance. A ship with stealth and cloaking defences can be considered a Spy ship.
Sniper
This configuration has decent firepower, and can take advantage of the superior sensors to deliver long range damage with high accuracy.
Transport Types
The nature of transporting valuable troops and ships makes such vessels intrinsically more vulnerable, since much of its mass is taken up as cargo space rather than as useful combat equipment. The ships themselves are actually cheaper than normal due to having to carry air space instead. However, the forces inside cannot contribute to the ship’s combat effectiveness until they are outside, which makes thus makes the ratio of the ship’s features much less important. Ships with a plurality of space devoted to transport are defined as follows:
Freighter
These ships carry resources and supplies between worlds.
Tanker
These ships carry fuel for other ships. They are useful in allowing more firepower and defence heavy ships to travel faster, but come at the cost of being vulnerable to destruction.
Collector
A special ship designed to collect easily extractable resources such as fuel from gas giants and asteroids.
Extractor
A special ship for extracting more difficult to collect resources.
Supply Vessel
These ships carry supplies for the rest of the fleet. They have shuttles for couriering their supplies enroute. This allows the warships to not have to carry so much stuff that’s not important to battle. Protecting these ships during combat is important.
Ferry
A short range ship for carrying people a short distance.
Liner
A long range ship for carrying people a long distance.
Troopship
These carry people, supplies, planetary troops, and shuttles between planets. In order for a troopship to carry out an invasion or launch raids on enemy ships they must carry assault shuttles. Aside from shuttles they do not carry any spaceworthy ships the way a carrier does.
Carrier
Often about as heavily armoured as a battleships, but with minimal guns (mostly defensive), the carrier instead relies on its squadrons of fighters and bombers to provide firepower, effectively providing an orbit for these ships. Carriers can actually carry any orbital craft, spaceplane, or ship that can fit within its hanger bay. Yes, that means you could carry and deploy a battlestation if you wanted. This is actually a legitimate strategy.
Supercarrier
A much larger carrier with even stronger defences, these ships must often be built in a separate orbit from the shipyards and are too large to dock at a space station. They are however large enough to function as docks for carrying smaller warships and satellites
Other
Ram
A peculiar designation for a peculiar class of ship, ram ships are rarely seen in traditional space navies. Rather, they tend to used by more unconventional forces such as the Dominion Machinarum, or the Alien Nation. These ships carry no conventional weaponry, and instead focus almost entirely on defences and propulsion, often combined with stealthy designs. As such, they are exceedingly tough, exceedingly fast, and exceedingly difficult to detect, the necessary requirements for a ship whose only strategy is to literally ram through enemy vessels at dangerously destructive velocities. While one would assume such a mission to be suicidal, the design of these ships often entails the ability to survive for another run. A fleet of charging ram ships is a deceptively terrifying sight to an inexperienced commander, particularly before the era of effective kinetic resistance shields.