Propulsion

Although vessels of all types regularly use their orbital thrusters and occassionally use other technologies such as chemical rockets during interplanetary maneuvering, three main technologies dominate long distance propulsion: ion drives, ramscoop ion drives and solar sails.

Each of these has advantages and disadvantages while sharing the basic advantage of very high fuel efficiency.

Solar sails
Although bulkier and more expensive than the other two options, sails require no power to operate. This brings the overall cost back in line. The benefit of lower crew and maintenance requirements usually tip the balance in favour of sails.

The disadvantages of sails are their extremely high detection signature and their lower maximum acceleration and peak velocity. They are also affected by the distance from the star but this is oftn compnsated for by the use of broad area (and thus effectively low power) lasers

Ion Drives
Although Ion drives require reaction mass, the amount is minimal in comparison to even the most efficient thrusters. It is common practice to utilise "waste" products from other ship systems for this purpose.

Ion drives are the mid-range choice, requiring the most power but with very few other disadvantages.

Ramscoop Ion drives
Scoops harvest the interplanetary medium for their reaction mass. Within the boundaries of a solar system, the ready availability of mass means they can be far less intense with their power usage compared to regular ion drives as a trade off.

The single biggest drawback of this drive system is the increased vulnerability in combat caused by the ramscoop itself. While the detonation of a warhead nearby may cause some damage and temporary destabilisation to a solar sail, the effect on an active ramscoop will often be dramatic and catastrophic as it "sucks in" the high energy particles and radiation, overloading the system.