The Effect of Aerodynamic Surfaces Versus Thrust Maneuvers on Reentry Vehicles

This research effort analyzes the effect of aerodynamic surfaces versus thrust maneuvers on a reentry vehicle. At high altitudes the effect of aerodynamic surfaces on the reentry vehicle is small due to low atmospheric density; however as the vehicle reaches lower altitudes a lift maneuver is very successful in deflecting the vehicle and creating a large impact footprint. When a continuous thrust maneuver is input in the place of a lift maneuver the results are very similar at the highest maneuver altitudes, although the impact footprint shrinks rapidly as the maneuver altitude decreases. Additionally, when the thrust maneuver is along or opposite the velocity vector of the vehicle it significantly alters the time of flight, especially when performed at higher altitudes. In order to perform this analysis, a FORTRAN program using the equations of motion for a reentry vehicle was modified in order to accommodate the lift and thrust maneuvers.