Mass Drivers

Mass drivers are magnetic launch mechanisms that rapidly accelerate payloads to significant relative velocities. Used in a variety of civilian and logistical infrastructure, mass drivers allow small payloads to efficiently achieve orbital and interplanetary velocities. The typical configuration is a long-barreled magnetic track, down which the payload accelerates at a tolerable rate. Payloads must be capable of self-propulsion if their launch velocity does not place them at their target orbit. Mass drivers can be based in space or on planetary bodies, and are most effective when operating through limited atmosphere.

Mass drivers are commonly used to launch a variety of payloads off of planetary bodies including mining exports, orbital infrastructure, and interplanetary spacecraft. Long enough tracks can be used to launch people and other precious cargo.

Configurations

A limitation of surface-based mass drivers is their fixed orientation. They cannot be moved or rotated (relative to the surface) once constructed, and as such the long-term use of the infrastructure, including its surroundings and its target orbits, must be considered. The rotation and orbit of the host body plays a key role in this decision. Common sites are at equatorial ranges and high elevations.

Space-based drivers do not have a fixed-direction issue. They can be reoriented and relocated, albeit quite slowly; a single track may be only several meters thick but kilometers long, requiring precise thrust along its length so as not to stress the structure.

Railguns

The militarized version of the mass driver is the railgun. A typical railgun uses an extremely short track, usually only a few times longer than the length of the payload. The accelerations imparted on railgun rounds are immense, limiting payloads to solid pieces of hardy metal. Railgun snipers may use longer barrels, but these are generally more vulnerable to attack.

Read more: Railguns