A hyperspacial aggregation motor[1] (or field engine[2]) was a spacecraft propulsion device allowing for faster-than-light travel in hyperspace. The motor functioned by using engine fields to gain "traction" on[3] and push against the energy grid.[4]

Larger motors performed disproportionately better relative to smaller motors.[5]

Motors were constructed of exotic material.[4]

It was faster and more advanced than warp propulsion.[6][1]


Fast spacecraft tended to have a larger proportion of their mass devoted to motors.[4]

Care needed to be taken when engaging motors deep within a gravity well.[7]

A high speed crash-stop produced a disturbance in the energy grid; the unleashed energies could break through the skein–into real space–in a manner similar to a gridfire.[8]

Intergalactic speeds were much slower than intragalactic speeds. The energy grid was more "tenuous" outside galaxies, making it more difficult for engine fields to gain traction.[9]

A failed attempt to gain traction when "hitting the ground running" caused an energy backlash. In such a scenario, motors were designed to bleed off the energy by partially ablating; the ablation was visible to long-range sensors as an ablationary plume. The motors were disabled, and the spacecraft slowed. Without ablation the spacecraft would be seriously damaged or destroyed.[2]


  1. 1.0 1.1 Surface Detail, chapter 19
  2. 2.0 2.1 Surface Detail, chapter 21
  3. Consider Phlebas, chapter 9
  4. 4.0 4.1 4.2 Excession, chapter 7.2
  5. Surface Detail, chapter 13
  6. The Player of Games, chapter 2
  7. The Hydrogen Sonata, chapter 5
  8. Excession, chapter 11.6
  9. The Player of Games, chapter 1