Hypersonic flight performance improvements by overfueled ramjet combustion

The first part of the paper deals with performance characteristics of hypersonic airbreathing engines. This concerns the effect of overfueled combustion 0n thrust and specific fuel consumption and other factors such as combustion temperature, real gas effects and pollution due to exhaust gas. Furthermore, effects on engine size and weight are addressed and installation drags associated with inlet/engine mismatch is considered. In the second part of the paper, flight mechanics topics which may support the use of overfiieled ramjet combustion are considered. It is shown which improvements can be achieved in terms of enhancing performance criteria adequate for the flight maneuver types considered. The considerations also include the possibility of reducing the overall fuel consumption of a flight maneuver despite an increase in specific fuel consumption. For solving the above flight mechanics problems, efficient mathematical optimization techniques are applied. Thus, it is possible to deal with complex dynamic systems like two-stage to orbit (TSTO) vehicles for hypersonic flight and to produce realistic results.