An Air-Launched Hypersonic Vehicle Performance Model

Abstract

A new performance model was developed for hydrocarbon fuelled (Jet A) scramjet powered hypersonic systems. It was applied to air-launched hypersonic missile concepts that were boosted to a specified Mach number (3) and dynamic pressure (40-100 kPa) using a solid propellant rocket motor. After boost, a dual-mode airbreathing supersonic ramjet engine accelerates the missile concept along a constant dynamic pressure, ballistic trajectory until it reaches a prescribed cruise Mach number (4-9). The performance model integrates the equations of motion over the entire mission and therefore takes into account variations in aerodynamic trim due to fuel consumption. Results show that fuel storage capacity has significant effect on vehicle range and average speed. A sensitivity study was also performed that investigated the effects of changing 14 design parameters on overall range. It was shown that the kinetic energy efficiency (entropy gain) of the propulsion system had the highest affect on performance followed by structural mass, combustion efficiency and aerodynamics parameters.