Numerical prediction method of reentry trajectory planning based on quasi equilibrium glide condition

Based on the quasi equilibrium glide condition (QEGC), a numerical prediction method of three-dimensional reentry trajectory planning is presented for hypersonic vehicles with constraints. In this paper, both the angle of attack and the bank angle are seen as the control variables, so the QEGC can be fully used. Firstly, the range and the terminal velocity is predicted numerically according to the profiles of the angle of attack and the flight path angle respectively. Secondly, the bank angle is then calculated to keep the trajectory flying along with the QEGC, and the path constraints in flight are transformed into the bank angle constraints. Finally, the simulations for the CAV-H are constructed. The simulation results demonstrate that the proposed method can make the trajectory smooth enough, and has flexibility for different targets.