Aerojet
successfully validated its design of a revolutionary tri-fluid propellant
injector for non-toxic hydrogen peroxide engines. The injector is a component
of the Advanced Reusable Rocket Engine that Aerojet is developing for the Air
Force’s Space Maneuver Vehicle.

The hot fire testing in February and March demonstrated the injector’s
performance capabilities including its reliable ignition and its stability
even at twice the normal throttling range. Tests were conducted on a sub-scale
version of the injector using two different injector patterns. Both performed
successfully, and one will be chosen for the full-scale tri-fluid injector.
Test results indicate that acceptable performance was achieved for both
element types. Also, the injector element chug threshold was much lower than
anticipated and will serve to provide additional throttling capability well
beyond what is required.

“The tri-fluid injector is an invention that will enable a closed-cycle
hydrogen peroxide engine to perform similarly to conventional toxic rocket
engines while providing high throttleability for a variety of vehicle
missions. Completing this testing has validated our injector element design
and significantly reduces the risk as we move forward into full-scale
testing,” said Dave Gallet, Aerojet Advanced Reusable Rocket Engine program
manager.

What makes the tri-fluid injector unique is that decomposed peroxide, used
to drive the turbopump, is exhausted into the tri-fluid injector to ignite the
engine’s hydrogen peroxide and jet fuel propellants. This creates a closed-
cycle engine system that does not dump propellants overboard like a typical
gas generator cycle engine. The result is higher performance and a wider range
of throttleability.

Detailed design of the full-scale tri-fluid injector is nearing
completion. Hot fire tests are planned for late summer 2002. Aerojet is
conducting all injector tests in its new, state-of-the-art peroxide engine
test facility, which was built for hands-on development of rocket engines
containing environmentally friendly hydrogen peroxide propellants.

Aerojet’s Advanced Reusable Rocket Engine is a non-toxic, hydrogen
peroxide engine that utilizes advanced injection concepts, fabrication
processes and chamber materials. The Air Force’s Space Maneuver Vehicle is an
unmanned space vehicle envisioned as a reusable satellite bus. The ARRE also
has applications on the Space Launch Initiative, NASA’s effort to develop
technologies for a second-generation reusable launch vehicle.

Aerojet, a GenCorp company, is a world-recognized aerospace and
defense leader principally serving the missile and space propulsion, and
defense and armaments markets. Aerojet’s Web site address is
http://www.aerojet.com.