Optimization multiple-turn trajectories of interorbital flights of spacecraft

Problems of multiple-turn trajectories optimization of flights between complanar circular orbits of an Earth satellite of a spacecraft equipped with the high limited thrust rocket engine with the thrust vector control are considered. Mass expenditure is minimized during limited flight time. Optimal control problems are solved numerically on the base of the maximum principle. Boundary problems are solved with shooting method. Extreme multiple-turn trajectories are determined. Regularity of construction and attributes of extreme trajectories of the best structure are revealed. The simple scheme of constructing the multiple-turn trajectories near to extreme ones which allows to choose the optimal structures for multiple-turn trajectories is proposed.