New RS-25 production run nears

As the next series of RS-25 engine test firings at the Stennis Space Center, Miss., nears, Aerojet Rocketdyne is assembling the new components of its “production restart” design and fabricating the parts for new flight engines. Aerojet Rocketdyne’s RS-25 program is primarily based out of its Canoga Park facility in the Los Angeles area, where most of the engineering and production of the engines is done. All of the flight engines are planned to be delivered to NASA by July, 2024. The new engines are due to begin flying on the fifth Space Launch System (SLS) launch. The SLS program has 16 engines left over from the Space Shuttle era, which will be used on the first four launches – four engines per launch. The engines are modified from their Space Shuttle configurations to operate at a higher power level and more severe thermal environment. They went through extensive ground testing from early 2015 through late 2017. Changes to the engine design will be certified in part during dozens of ground test firings at Stennis, grouped into a series of tests on different ground test engines. The first production restart test series, called “Retrofit 1a,” was completed in late February. That series demonstrated the first major production restart component, the pogo accumulator assembly. The pogo units are now built using a 3-D printing technique. The last of four hot-fire tests saw development engine 0528 (E0528) throttled up to a record 113 percent RPL. The upcoming Retrofit 1b test series is currently targeted to start in the A-1 test stand at Stennis in mid-August. Following the completion of the rapid-turnaround demonstration of the AR-22 engine, Aerojet Rocketdyne’s other SSME derivative, E0525 was delivered to the stand on July 23 for installation. (Source: NASA Spaceflight, 07/31/18) Previous related: Testing of AR-22 underway;