Annotation: Mission control of the orbital space plane is one of the actual and complicated applied problems of the theory of mobile objects control. Dynamic configuration of this plane as an object of control is described by the system of non-linear differential equations of higher order. Research of stability of such system is a difficult problem. However, thanks to known theorems of Lyapunov, often stability of the real system can be estimated by the roots of the characteristic equation of the linearized system. Thereupon the stability analysis in the linear setting is the necessary link in the process of orbital space plane control system development. Among the methods of synthesis of the automatic control linear systems developed to date one can emphasize the trend, which has become widely-spread in the engineering area. According to this trend the issues of synthesis of the dynamic regulator, observability and controllability for the orbital space plane are considered. Procedure of selection of the dynamic regulator parameters at the early phase of development of the control system for the orbital space plane motion about the center of mass is suggested. Observability and controllability of the orbital space plane are considered. It is shown that the considered control system of the orbital space plane is observable and controllable, i.e. it is possible to develop the stable dynamic regulator, which provides the required speed and accuracy of the angular position of the orbital space plane during the orbital flight. Factors selection procedure is offered for the factors being the part of the control laws for the control system actuators.

Annotation: The article dwells on the spacecraft attitude control to point the onboard antenna to the ground data acquisition station during the communication session. Antenna is fixed relative to the spacecraft body. Pur-pose of the antenna is to receive the flight task aboard the spacecraft and to downlink the telemetry infor-mation. When orbiting, the spacecraft position relative to the ground data acquisition station changes contin-uously. It is due to the diurnal rotation of the Earth, spacecraft orbital motion and angular motion of the spacecraft relative to the center of mass under the impact of the disturbing and control moments. To tilt the spacecraft uses reaction wheels, installed in axes of coordinate system coupled with spacecraft center of mass. Electromagnets are used to unload the reaction wheels. The reaction wheels control law is suggested, which tilts the spacecraft to point the antenna to the ground data acquisition station. Mathematical model of the spacecraft dynamics relative to center of mass is given, using the suggested reaction wheels control law. The following external disturbing moments, acting on the spacecraft in flight, are taken into consideration: gravitational, magnetic, aerodynamic moments and solar radiation moment of forces. Dipole model of the magnetic field of the Earth is used to calculate the magnetic moments. Software was developed and space-craft dynamics was simulated on the personal computer with the specified initial data. Simulation initial con-ditions correspond to the attitude control mode of the spacecraft relative to the orbital coordinate system with the specified accuracy. Simulation results verify the applicability of the suggested reaction wheel control law.