Analytical solutions for reentry of the spatial vehicles in atmosphere

Abstract

In the dynamics of spatial vehicles reentry into the earth atmosphere, an important factor is the existence of aerodynamic forces. The mathematical model adopted regarding optimal atmosphere re-entry considers the lift - drag ratio as being constant. Actually, the aerodynamic coefficients vary with the flight velocity and altitude, a hypothesis used in this study. Thus, the system that represents the motion equations of atmosphere re-entry changes into an equivalent system with small parameters. The analytical solution of this system is expressed through the variable defined by atmospheric density.