The prospect of responsive spacecraft using aeroassisted, trans-atmospheric maneuvers

Comprised of exo- and trans-atmospheric trajectory segments, atmospheric re-entry represents a complex dynamical event which traditionally signals the mission end-of-life for low-Earth orbit (LEO) spacecraft, both manned and unmanned. Transcending this paradigm, atmospheric re-entry can be employed as a means of operational maneuver whereby the aerodynamic forces of the upper atmosphere can be exploited to create an aeroassisted maneuver. Utilizing a notional trans-atmospheric, lifting re-entry vehicle with L/D=6, the first phase of research demonstrates the terrestrial reachability potential for skip entry aeroassisted maneuvers. By overflying a geographically diverse set of sample ground targets, comparative analysis indicates a significant savings in DeltaV expenditure for skip entry compared with planar phasing and simple plane change exo-atmospheric maneuvers. In the second phase, the Design of Experiments method of orthogonal arrays provides optimal vehicle and skip entry trajectory designs by employing main effects and Pareto front analysis. Depending on the chosen re-circularization altitude, the coupled optimal design can achieve an inclination change of 19.91 deg with 50-85% less DeltaV than a simple plane change. Finally, the third phase introduces the descent-boost aeroassisted maneuver as an alternative to combined Hohmann and bi-elliptic transfers in order to perform LEO injection. Compared with bi-elliptic transfers, simulations demonstrate that a lifting re-entry vehicle with L/D=6 performing a descent-boost maneuver requires 6-12% less DeltaV for injection into orbits lower than 650 km. In addition, the third phase also introduces the "Maneuver Performance Number" as a dimensionless means of comparative effectiveness analysis for both exo- and trans-atmospheric maneuvers.