Impulse drive is the most common form of sub light propulsion in the known galaxy. It is significantly less complicated than warp drive any relies on conventional exhausting of hot gasses to create propulsive effects.

Starfleet Impulse drives consist of four basic components: Impulse Reaction Chambers (IRC three per engine), Accelerator Generator (A/G), Driver Coil Assembly and Vectored Exhaust Director (VED). These components are connected as below. The diagram also shows additional systems which will be explained later in the article:

Impulse Reaction Chambers.

The IRC is an armored sphere six meters in diameter, designed to contain the energy released in a proton-proton fusion reaction. Slush deuterium is fed into the sphere where a standard pulsed fusion shock front is created by the standard initiators ranged about the forward inner surface of the sphere initiating the fusion processes.

Accelerator Generator.

The high energy plasma created during the engine operation is exhausted via a central opening in he ICR into the A/G. This stage is generally cylindrical and about 5.8 meters in diameter. During operations the accelerator is active and accelerates the velocity of the plasma passing it onto the driver coil assembly. Some impulse drives such as those on Starfleet vessels have the ability to disengage this stage and re-route the output of the IRC's through EPS power taps and into the main EPS power grid. This facility provides a back up power source.

Accelerator Generator.

The A/G is 6.5 meters long and 8.5 meters in diameter and is made up of a series of six split toroids. Energy form the accelerated plasma when driven through the toroids creates a necessary combined field effect that generates a low level sub space field. The sub space field allows the starship to effectively partially slip into sub space reducing its mass. With a reduced mass high velocities can be reached on huge starships which would otherwise be virtually unmovable.

Vectored Exhaust Director. The final stage is the VED consisting of a number of movable vanes and channels designed to expel exhaust products in a controlled manner. The VED is capable of steerable propulsive and nonpropolsive modes (simple venting).

Engine Control.

The impulse propulsion system is commanded through operational software and routines stored within the main computers. Learning from ongoing experiences these programs control all of the stages of the drive system to give the desired effects from the commands fed to it form the bridge or main engineering. The commands are first sent to the main computer that makes any necessary calculations and verifications from there the relative instructions to the IPS co-ordinator which initiates the necessary actions. The IPSCC is also cross linked with the reaction control system (RCS) for attitude and translational control at speeds to argment the exhaust vectoring.