RL-10 successfully completes hotfire tests
The use of 3D printing in spaceflight took another step forward in early 2018 when Aerojet Rocketdyne completed a series of hotfire tests of a new model of the RL10 rocket engine which was built almost entirely of 3D-printed parts.
Last year, the company produced a 3D-printed thrust chamber assembly and subjected it to a series of successful tests. The current version of the RL10 engine uses an array of stainless steel tubes that are brazed together to form the thrust chamber.
By incorporating 3D printing, Rocketdyne hopes to reduce the lead time by several months. This could also reduce costs.
“Hot-fire testing helps us validate the approaches we are using to fabricate and join parts that are produced through additive manufacturing to ensure they meet our requirements for materials characterization, structural integrity and durability. We are also able to accurately define the amount of heat-transfer that is taking place so we can optimize the performance of our next generation of RL10 engines,” Senior Program Director Christine Cooley explained. via a company-issued release.
The latest round of tests took place at the one of the company’s facility in West Palm Beach, Florida, and incorporated a new, 3D-printed thrust chamber made of a copper alloy, which makes use of a new, 3D-printed nickel-based nozzle that is regeneratively cooled. This means that propellant is passed through channels around the combustion chamber. The fuel makes for a good coolant, so it keeps the temperature of the engine down and then heated propellant is injected into the nozzle.
“This recent series of hot-fire tests conducted under our RL10C-X development program demonstrated the large-scale additive manufacturing capability we are maturing to help reduce the cost of this legendary engine system while continuing to provide reliable performance. This marks another important milestone in our effort to fully qualify components built with additive manufacturing for use in many of our production engine systems,” Eileen Drake, CEO of Aerojet Rocketdyne, stated regarding the recent tests.
Drake also hopes that 3D-printing can open up new creative design spaces. “This latest round of testing demonstrates that we can systematically print and assemble an engine that can replicate the proven RL10 performance in a fraction of the time and at a reduced cost. Additive manufacturing technology also enables new approaches to engine design that we are now exploring through sub-system testing and validation.”
The RL10 engine has been in use since 1959, and has been utilized to launch probes to explore every planet in the Solar System. A single RL-10 is also being designed to power the Cryogenic Propulsion Stage of NASA’s Space Launch System (SLS), and four RL10s will power the new super-heavy launch vehicle’s Exploration Upper Stage.
Collin R. Skocik has been captivated by space flight since the maiden flight of space shuttle Columbia in April of 1981. He frequently attends events hosted by the Astronaut Scholarship Foundation, and has met many astronauts in his experiences at Kennedy Space Center. He is a prolific author of science fiction as well as science and space-related articles. In addition to the Voyage Into the Unknown series, he has also written the short story collection The Future Lives!, the science fiction novel Dreams of the Stars, and the disaster novel The Sunburst Fire. His first print sale was Asteroid Eternia in Encounters magazine. When he is not writing, he provides closed-captioning for the hearing impaired. He lives in Atlantic Beach, Florida.