Aerojet Rocketdyne Continues Work on Rocket for Lunar Return

NASA finished the 3rd of a series of 12 ground tests of the SLS rocket that will one day power Artemis program missions to the moon - and beyond.

The RS-25 engines are swinging for the fences in a change from the norm around NASA, where uncrewed, spacefaring drones became the norm. Manned missions require a lot of thrust, and the aged, handworked Saturn V was simply too difficult to recreate today without retreading significant design ground. The RS-25 will boast the best tech that they can build today, with all kinds of additive manufacturing and computer optimization allowing for futuristic improvements in weight and output (hopefully quality, too but only time will tell.) As installed, 4 engines will generate a combined 1.6 million pounds of thrust at launch, and 2 million during ascent. Artemis missions I through IV will use "modified holdover space shuttle main engines", scavenged by NASA and Aerojet Rocketdyne in a feat of thriftiness.

The 11-minute hot fire occurred on the Fred Haise Test Stand at NASA’s Stennis Space Center near Bay St. Louis, Mississippi. This one wasn't a garden variety static test, either, being used to test the engine's gimbaling techniques that will one day prove vital to control and stabilize the SLS as it reaches orbit. As part of the test, operators "also pushed the engine beyond any parameters it might experience during flight to provide a margin of operational safety." In practice, the RS-25s will fire for 500 seconds straight, while the test took one straight to 650 seconds of burn. Even better to stress-test it, the RS-25 was fired up to 113% of regular output, exceeding the "111% needed to lift SLS to orbit."

FMI: www.nasa.gov