An advanced liquid methane-fueled rocket engine designed with the goal of bringing astronauts back from the Moon completed altitude testing in late April at NASA’s White Sands Test Facility in New Mexico, the engine’s manufacturer announced May 4.
The engine, developed by Aerojet under the NASA Exploration Systems Mission Directorate’s Propulsion and Cryogenics Advanced Development Project, burns a combination of liquid oxygen and methane (LOX/methane) to produce 5,500 pounds of thrust.
Joe Cassady, director of emerging space systems for Sacramento, Calif.-based Aerojet, said in a May 6 interview that the company completed eight separate test firings of the engine inside White Sands’ Test Stand 401, an altitude chamber that uses old rocket engines to pump out nearly all the air. Cassady said the 40-second test that closed out the campaign was done under atmospheric conditions a rocket would see at an altitude of more than 36,500 meters. During the tests, the engine demonstrated a specific impulse of 345.2 seconds, giving Aerojet confidence that a flight configuration engine would be capable of 350 seconds of specific impulse.
A sea-level testing campaign completed in the summer of 2009 consisted of more than 50 hot fire tests for a total duration of 769 seconds, Aerojet said in a press release.
When NASA selected Aerojet in April 2008 to build the engine, the U.S. space agency intended to use a comparably sized methane engine on the ascent stage that would lift the then-planned Altair lunar lander off the surface of the Moon. NASA has since been told to forget about sending astronauts to the Moon and to begin planning a new human spaceflight program that aims to send astronauts to an asteroid in 2025.
Cassady said LOX/methane engines could still find a role in NASA’s exploration plans despite a White House decision to cancel Altair and the rest of the Moon-bound Constellation program.
“It’s really being seriously looked at now for a lot of the in-space stuff,” Cassady said, referring to NASA’s intent to build and flight demonstrate a new liquid-fueled upper-stage engine under a $3.1 billion Heavy Lift and Propulsion initiative proposed as part of the agency’s 2011 budget.