Aerojet, a GenCorp
Inc. company, recently conducted a successful hot fire test program
for a non-toxic reaction control engine utilizing liquid oxygen (LOX) and
ethanol as propellants. The reaction control engine (RCE) is being developed
for NASA’s Marshall Space Flight Center and the Exploration Systems Mission
Directorate as a relevant technology that is applicable to the Vision for
Space Exploration. The engine testing validated the operability of a cryogenic
LOX-ethanol reaction control engine and ignition system in both steady state
and pulse mode operation. It included long duration steady state operations up
to 240 seconds and numerous pulse mode operations typical of ascent, on-orbit
and re-entry operations.
The testing also included the evaluation of the effects of chamber
pressure and mixture ratio variations on the engine, combustion chamber
thermal response, and six different pulse duty cycles between 80 milliseconds
and ten seconds. Chamber temperatures were as predicted and uniform in steady
state and during pulsing, validating Aerojet’s capabilities in controlling the
injection and combustion process through the use of proprietary platelet
injector design.
“With this testing, Aerojet again demonstrated the value of our unique
platelet technology,” said Aerojet RCE Program Manager Eric Veith. “The
platelet technology distributes the LOX and ethanol propellants in a more
uniform manner, thus producing an even mixture ratio, which provides efficient
and uniform combustion.”
Pulse mode testing was conducted to demonstrate the operability
requirements for minimum pulse widths for a liquid-liquid auxiliary propulsion
system that used LOX Ethanol. Aerojet worked closely with its suppliers, Moog
and Castor Engineering, to develop LOX & Ethanol main injector and igniter
valves that operated to meet the required pulse mode operations.
“The successful demonstration of a cryogenic liquid-liquid reaction
control engine steady state and pulse mode testing provides the technical
foundation for the next step in the LOX-based reaction control system
development,” Veith said.
Oxygen-based propulsion systems offer several advantages over
hydrazine-based systems including improved operability, reduced environmental
impacts and the potential for in-situ propellant production beyond Earth’s
surface.
Aerojet plans to build, hot fire test and deliver three engines for system
level testing by NASA during summer 2005 at White Sands Test Facility,
New Mexico.
Aerojet is a world-recognized aerospace and defense leader principally
serving the missile and space propulsion, and defense and armaments markets.
GenCorp is a technology-based manufacturer with positions in the aerospace and
defense and real estate industries. Additional information about Aerojet and
GenCorp can be obtained by visiting the Companies’ web sites at
http://www.aerojet.com and http://www.GenCorp.com .
