dehammer, yes but you can change the design of such a system so that it can be made to work.

In space there is no friction, so in principle no you can win back all of the kinetic energy. The question is how this can be implemented in practice. You could think of a sort of maglev train in space. When the track ends it has accelerated to a certain speed and floats through space until it reaches its destination. At the destinatian it could brake inside a coil by generating induction currents. That energy could be stored and yused to propel a spacecraft on the way back.