Spike drive

The spike drive is the means by which faster than light (FTL) travel is accomplished. Spike Drives were first created in 2108 by Dr. Tiberius Crohn, an engineer from the origin planet, Earth. The first functional postech spike drive was designed and tested by Ramirez al-Mualim, the founder of the well regarded University of Anaximander.

A spike drive allows a ship to "drill down" into subspace, where relativistic physics does not apply, allowing ships to move at speeds far surpassing those possible in normal space. Through intensive testing during the early years of spike drive usage it was discovered that large gravitational effects, such as those caused by stars, interfered with the fields created by the spike drive making it unsafe to use a spike drive within star systems. As such FTL travel is only possible between systems and not within them, causing the curious effect that it takes almost as much time in real space travelling through systems as between them in subspace when performing such long distance travel.

Fighter pilots and later those piloting larger ships discovered that, during combat, it is possible to use the spike drive to put the ship slightly out of phase with the opponent allowing weapons fire to pass through the ship as if it wasn't there at all. In a space battle, anticipating the phase your opponent is going to be in at any given time is just as important as evasion and targeting.

Currently, spike drives are split into 6 tiers according to the speed of travel they are capable of providing: Each tier of spike drive is also capable of putting a starship into greater levels of phase shift during combat. As you go up the tiers, the number of phases other than real space available matches the number of the tier.
 * Spike Drive-1 - Standard spike drive. Takes 6 days to travel to a neighboring system.
 * Spike Drive-2 - First upgrade to the standard drive. Takes 3 days to travel to a neighboring system.
 * Spike Drive-3 - Second upgrade. Takes 2 days to travel to a neighboring system. Most advanced post-tech drive.
 * Spike Drive-4 - Advanced pre-tech drive. Takes 1 and a half (6/4) days to travel to a neighboring system.
 * Spike Drive-5 - 5th tier drive. Takes 1 and a fifth (6/5) days to travel.
 * Spike Drive-6 - Most advanced pre-tech drive. Takes 1 day to travel to a neighboring system.