Abstract
The heliocentric motion of the solar sail spacecraft (SSS) is described in classical Keplerian elements. The solar sail with an ideal reflection coefficient is considered. The spacecraft performs a non-coplanar motion with the sun gravity and the light pressure. Disturbances of other celestial bodies gravity are not considered. To confirm the results correctness, we simulated the motion of solar sail spacecraft. The spacecraft's initial orbit coincides with the average Earth orbit relative to the Sun. Authors developed a program complex to simulate the planar heliocentric movement and obtained results for motion simulation of flights to Venus. The results were compared with the simulation results obtained using the Pontryagin maximum principle.