Abstract:

Performance requirements of turbo-jets for combined air-breathing-rocket spaceplanes are different from those for most of today's supersonic engines. These requirements had been parametrically investigated in earlier publications, based on the booster stage of the DSL TSTO-concept. The selected engine type and the consolidated target data will be described in this paper. The propulsion system figures are calculated for the DSL supersonic carrier aircraft (Mach-number range 2.7 to 3.5), but are transferable to supersonic and hypersonic systems with similar propulsion.

A preliminary design variation of the advanced technology air-breathing engine, including the air-intake and the nozzle, is executed. Dimensions and weights of the intake and the nozzle are estimated regarding the flight performance along the trajectory. Using a newly developed fast analytical design-tool in combination with computer aided design and finite-element calculations, render possible the variation of different configurations. More sophisticated calculation methods and improved engine design has been introduced since a proceeding publication. In consequence, the difference between current and advanced technology material becomes more striking.

A low bypass, moderate OPR turbofan engine, a vertical ramp, mixed compression intake, and a large symmetric nozzle will be selected. Advanced material and construction methods are found to be necessary for incorporation in the design, since current technology procedures yield prohibitively high mass values. The paper includes five mass breakdowns with different fabric selections for the main engine parts. Based on that the propulsion system weight is estimated. In conclusion the complete propulsion system thrust to weight ratios are assessed along the configurations trajectory.