The disclosed method involves calculating, with at least one processor, a desired orbit for the spacecraft. The method further involves calculating a velocity change required to achieve an orbit eccentricity, a velocity change required to achieve a semi-major axis, and a velocity change required to achieve an orbit inclination; all of which correspond to the desired orbit for the spacecraft. Also, the method involves calculating the direction of the vector sum of the velocity change required to achieve the orbit eccentricity, the velocity change required to achieve the semi-major axis, and the velocity change required to achieve the orbit inclination. Further, the method involves activating at least one propulsion device of the spacecraft in the direction of the vector sum in order to change the current orbit of the spacecraft to the desired orbit for the spacecraft, thereby changing the orbit eccentricity, the semi-major axis, and the orbit inclination simultaneously.