INTEGRATION AND VEHICLE PERFORMANCE ASSESSMENT OF THE AEROJET "TriJet" COMBINED-CYCLE ENGINE

†This paper presents the results of an internally funded joint study between Boeing and Aerojet to develop and evaluate the performance potential of a hypersonic cruise vehicle incorporating Aerojet’s novel TriJet combined-cycle propulsion system. The results were compared to an earlier Aerojet turbine-based combined cycle propulsion system concept, named PyroJet, that requires a future Mach 4 class turbine engine. The TriJet concept is a near-term solution providing the Mach 0-7 propulsion capability which makes use of currently available Mach 2.5 turbine engines, supplemented by an ejector ramjet to bridge the thrust gap between the available turbine and dual-mode ramjet operation. A hydrocarbon-fueled (JP-10) 75-ft-long vehicle capable of Mach 7 cruise was selected into which to integrate these propulsion systems. Range was chosen as the figure of merit for comparison purposes. The results indicate that the range capabilities of the two concepts are within 10% of each other.