Experimental Flight of a Spacecraft with Solar Sail

We analyze the prospects of launching an experimental spacecraft with a solar sail. The problems hindering the implementation of this task are discussed. The ways to solve these problems are pointed out. The feasibility of organization of a system of controlling this spacecraft with a small consumption of propellant mass is briefly investigated.     

Problems of control of a re-entry vehicle with a moderate lift-to-drag ratio during its entry into the atmosphere

We consider the problems of control of the angular and trajectory motion of the Kliper re-entry vehicle. This spacecraft with a moderate hypersonic lift-to-drag ratio is designed according to the load-carrying frame scheme. Gas-dynamic engines, a split balancing flap, and an air brake are used as mounting devices of control.     

Trajectory Control for a Spacecraft with an Inflatable Braking Device in the Martian Atmosphere

The possibility of using an inflatable braking device for controlled descent in the Martian atmosphere of large-capacity cargoes is analyzed. The most complicated version of the trajectory control problem is considered, namely, the injection of a spacecraft at hyperbolic velocity into a parking orbit after braking in the atmosphere.     

Estimation of a Satellite Lifetime in Orbit

An approximate technique for calculating the satellite orbit decay under the aerodynamic drag effect for arbitrary values of the orbit eccentricity and for the realistic model of the altitude dependence of the atmospheric density is proposed.