The research aims at developing new optimal control solutions to the general relativity problem applied to spaceflight trajectories, relating classical astrodynamics to relativistic physics. Specifically, the study addresses the problem of minimizing propellant consumption during a transfer between S-stars for a spacecraft powered by a high-performance Magnetic Confinement Fusion engine operating in the deep gravitational potential of the supermassive black hole Sagittarius A*. The central body is assumed to be a static, spherical, and non-rotating black hole, in order to model the gravitational field using the Schwarzschild metric, without restricting the motion to the equatorial plane, and under the boundaries of Einstein's General Relativity assumptions.