In my tables of colonies for Flat Black you will find a column of “Spaceport” codes, each of which consists of a digit and a letter. These are a legacy of ForeSight, the original native game system of Flat Black
The digits represent the amount of material, mostly freight, that is lifted from or landed on the planet, and therefore the total scale of its spaceport or spaceports. The scale is logarithmic base ten, rounded to the nearest whole number. Negative characteristics are recorded as “0”, As a result each size code covers a factor of ten in throughput, except scale 0, which covers everything from no traffic up to ₢316 million per year. The busiest spaceports in Flat Black are those of Simanta, which handle ₢300 trillion worth of freight per year, and are scale code 5. The planet with the least trade volume is Eppur, where only ₢14.7 million worth of freight is launched or landed each year. Eppur’s spaceport code would be -2N if negative scale rating were used.
The letters are type codes, as follows:
- N No formal facilities
- There are at best landing areas of firm rock or concrete, where you can get water to refill the propellant tanks in your lighter, fenced to exclude wildlife. Airports, for instance. At worst, you figure out somewhere safe to land that is as convenient as possible to the consignee of your cargo. The defining characteristic is that there is not lighter service operating from the colony. Cargoes cannot be delivered to orbit, and the ship that brings them has to carry a lighter with which to land cargo. That indicates a world to which a ship comes only at intervals of weeks, perhaps months. Otherwise it would be cheaper to park a cargo lighter in orbit rather than haul it around.
- G Ground facilities
- The planet has one or more dedicated landing facilities for cargo and passenger lighters, connected to surface and air freight networks, and having at least minimal resources to fuel, service, and repair orbital lighters. It also has some sort of surface-to-orbit service involving lighters that are kept in the system permanently. Cargoes can be delivered to orbit; ships serving the colony do not have to carry cargo lighters with them.
- O Orbital facilities
- There is at least one orbital spaceport, which has facilities for refuelling starships and at least minor repairs and service. Cargoes and complements of passengers are assembled in the orbital facility for quick loading and embarkation. Ships can be unloaded here expeditiously, the passengers and cargo waiting in the orbital facility for a lighter service to the ground.
Where there are orbital facilities there are invariable multiple, regional ground facilities and landing areas on the planet, connected by cargo and passenger lighters to the orbital facilities.
- T “Tower” facilities
- The code “T” denotes some sort of infrastructure for non-rocket space-launch. Actual tower facilities (beanstalks, orbital elevators) are unusual, because they are slow for passengers and cause inconvenience in the use of lower orbits. Aeneas and Todos Santos built towers (cheaply because of their short days) and are now considering demolishing them. Rotating skyhooks, termed “rotovators”, are more common at small planets, launch loops at large ones ones.
The orbital elevators at Aeneas and Todos Santos have spaceports in the tower facility at geostationary altitude. Other “T” infrastructure involves the payload being carried in orbital vehicles to rendezvous with an orbital spaceport or directly with a ship. T facilities provide cheap access to orbit for freight, but slow and inconvenience transfers from ground to spaceships for passengers. They therefore displace cargo lighter services but not passenger lighters.
Whatever spaceport facilities a planet has, there is always a landing field or ground facility in or adjacent to the Imperial extraterritorial enclave in each colony, secured and operated by the Empire. Only where trade volumes are low does this serve as the main commercial ground port of the colony.
The Empire built and operates the orbital ports of many colonies with modest development levels, and colonies with T and high O spaceport ratings often have one or more Imperial orbital facilities among their several orbital ports. In no case was the “T” infrastructure at any colony built by the Empire, nor does the Empire run any of those facilities.