A ship traveling through space is constrained by physical laws and relativity to sub-light speeds in any practicality. The Spacial Slipstream Drive provides higher sub-light speeds while protecting the ship and its occupants from the problems of time dilation.
Principles
By manipulating the fabric of space-time around a ship traveling through space such that the ship itself in encased of a bubble of modified space-time where time is manipulated inside the bubble to counteract the relative time distortions outside the bubble. The ships sub-light drive system can then interact with the edge of the space-time bubble. When the inside edge of the bubble has thrust against it, kinetic energy impacting the wall is amplified by distortion bubble and accelerates the ship at speeds amplified by two orders of magnitude from the associated sub-light velocity.
Operation
The enclosing bubble of space-time, separating the ship from the surrounding (normal) space-time is created using high energy lygon infused plasma generated by an Oscillating Mercury Core and routed to large field coils that create the actual bubble.
Speed Limits
A ships sub-light engines are seldom actually capable of approaching the speed of light in actuality, thus the sub-light velocity that is amplified has a general maximum of around 80% of the speed of light, though a ship traveling at such a high velocity without the use of a space-time bubble would be impacted by time dilation effects. There is a sizable gap between the highest practical sub-light velocity and the slowest slipstream velocity possible.
Flight Characteristics
Ships traveling at this velocity should decelerate before attempting to change direction. The same distortion field used to accelerate the ship can also be used to decelerate the ship to a more manageable speed to alter the flight path. Even altering the ships orientation while leaving its direction and velocity of flight the same, could prove dangerous due to the amplification effect of the distortion field.