After
its long journey from the fuel systems, the flow is finally directed down the
warp coils. These devices are large split toroids which take up the bulk of the
nacelle. In order to increase efficiency they are usually made from multiple
layers of various materials; this complicates the manufacturing processes
greatly and has - so far - kept the replication of warp coils beyond Federation
science.
The warp coils generate a multi-layered set of fields
around the craft, creating the propulsive forces that enable a Starship to
travel beyond light speed. Manipulation of the shape and size of the field
determines the velocity, acceleration and direction of the vessel.