No abstract

TRW has been developing a 870 Ibf thrust GO 2 -C 2 H 5 OH workhorse engine to demonstrate the feasibility of operation of this engine for non-toxic Shuttle Upgrade under NASA sponsorship. The use of non-toxic propellants will allow reducing cost and schedule for recurring Shuttle operations. The TRW engine offers a number of advantages for this application. The use of non-toxic propellants prevents corrosion of engine components for this engine based on the design and materials used which minimizes maintainability. The TRW engine offers a number of technical attributes that contribute to cost effective development. These include the ability to test many configurations in a short period of time by changing velocities/momentums in real time by shimming the oxidizer side, providing a fuel rich low temperature wall environment without separate fuel barrier cooling for low wall temperature operation, and providing a pintle injector that is dynamically stable without the use of damping devices. The engine has been tested in steady state operation only to date. Future pulse mode testing will be conducted with direct operated solenoid valves designed for this engine. This paper presents the design of the workhorse engine and the test results of this workhorse engine to date.