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Functionality and mechanics
Repulsor engines use stacked tidal gravity generators which create asymmetrical gravity fields that push and pull a ship through space in a desired vector, all without the need for reaction mass or conventional exhaust. An extremely sophisticated application of gravitics, these engines are powered by a ship's pinch fusion reactors. Modern repulsor engines are finely tuned and expected to operate for years without maintenance refreshes. However, the repulsor engines on older, vestigial warships—such as the drives outfitted on the Hekar Taa-pattern blockade runner — are cruder pieces of technology, requiring constant monitoring and adjustment to operate at full power.
A repulsor engine produces quantum fluctuations in its wake that are extremely hazardous to personnel and nearby vessels within its range, particularly when operating at high "thrust". These fluctuations are capable of interfering with the operation of gravitic technologies in the vicinity of the fluctuations. Prolonged exposure to unshielded repulsor drive elements can cause neurological degradation and even psychosis in most species - something the San'Shyuum considered largely beneath their notice.
- Four Callipoas-pattern repulsor engines are installed on the Ceudar-pattern heavy corvette. As part of Operation: UPPER CUT during the Fall of Reach, NOBLE Team and other FSS-1000 Sabre pilots disabled the four Callipoas-pattern engines of the Ardent Prayer to conduct a boarding action.
A Ceudar-pattern with Callipoas-pattern engines, confronting the UNSC Infinity.
A Ceudar-pattern vessel with green colored Callipoas-pattern engines over Casbah City.
Ceudar-pattern vessels with paler colored Callipoas-pattern engines at the Corbulo Academy of Military Science.