SLINCE Drive
The Super Long Inducting Navigational Coil Emergency drive (SLINCE drive) is a single-use drive system that is to be used in the event that the AYSE Drive fails. This drive cannot be deployed except in space due to the amount of open space required. There are three principal parts to the SLINCE drive: The launch coil, the Habitat coil, and the Earth-orbit receiving coil. The Habitat coil wraps around the hull of the Habitat, while the launch coil is stored in a compacted form beside the hab's fusion reactor.
The habitat uses a microburn to gain a small velocity with axial spin towards earth. The superconducting coil is then payed out at a constant rate to create a long coil directed towards earth. At the maximum possible deployment velocity, the coil takes a minimum of thirty minutes to deploy. The recommended deployment velocity results in a fifty minute deployment time. The hab then manuvers back to the beginning of the coil and, using all possible power, creates a launching force which accelerates the hab through the coil, and towards earth. If the TTC is still operable or the AYSE batteries are accessible, they are be utilised for this. Otherwise, the astronauts must attempt to sleep during the trip to Earth, as the Hab's reactor must store up sufficient energy to permit the induction of a 'braking' force when the hab passes through the permanent coil in Earth orbit.