Approximate Performance of PeriodicHypersonic Cruise Trajectories for Global ReachPreston

This paper develops the analytical framework to compare the approximate performance of periodic hypersonic cruise trajectories with previously proposed hypersonic trajectory prooles for global reach. Speciically, range, V and payload carrying capacity are evaluated for various trajectory types to illustrate the enhanced performance achieved by y-ing periodic hypersonic cruise trajectories with existing hypersonic vehicle aerodynamic, propulsion, and structures technology. Analytical results reveal that periodic hypersonic cruise trajectories achieve better fuel consumption savings over long distances (20,000 km) than other trajectory types proposed for high-speed ight. A 20+% improvement in fuel consumption savings is possible for a Mach 10 vehicle with a modest L/D=4, and a curve-tted rocket-based combined cycle engine model. h scale = Atmospheric scale height I sp = Speciic Impulse I sp e = EEective speciic impulse L = Lift m = mass m e = mass of engine m f = mass of fuel m p = mass of payload m s = mass of structure MF = Vehicle fuel mass fraction MR = Mass fraction n = Number of periods R = Range R e = Radius of the earth s = Length t = Time