May 5, 2024

NASA Upgrades Powerful SLS Rocket Engines – Production Restarted for Next Era of Space Exploration

” The RS-25 remains one of the most effective, powerful, checked, and flight-proven first stage engines in the world,” said Johnny Heflin, SLS liquid engines manager. Starting in 2015 with a series of hot fire tests on a set of shuttle-era ground test engines, the engine group adjusted the existing shuttle bus inventory to the SLS rockets distinct operating requirements for its preliminary deep area objectives by including engine nozzle insulation and establishing a new controller to replace the outdated shuttle bus engine controller.
Aerojet Rocketdyne of Los Angeles, California, has updated 16 RS-25 engines, that formerly flew shuttle bus objectives, with new control systems and has actually tested them at higher power levels needed for the very first 4 Artemis missions. With production on the brand-new engines in full swing, the brand-new design has one more hurdle: the series of hot fire tests to license the design for flight. A follow-on hot fire test series with a second certification engine will continue and begin this summertime through the fall to gather additional information.

The March 21 hot fire test of the RS-25 accreditation engine marked the 4th in a series focused on validating new engine production by Aerojet Rocketdyne, crucial for powering the Space Launch System throughout Artemis objectives to the Moon. Credit: NASA/Stennis
As NASA prepares for the first crewed Artemis objectives to the Moon, agency propulsion and test groups are setting their sights on future Space Launch System (SLS) flights and working to enhance among the worlds most effective and dependable rocket engines for missions starting with Artemis V.
A series of hot fire accreditation tests remains in development at NASAs Stennis Space Center near Bay St. Louis, Mississippi, for a redesigned RS-25 engine to support production of extra engines for future SLS flights after NASAs existing inventory of the engine is expended.
Originally created for the area shuttle bus, the RS-25 was chosen to power the SLS rocket since of its high performance and demonstrated dependability over more than a million seconds of ground test and flight time.

NASA effectively conducted a 10-minute hot fire of an RS-25 accreditation engine on March 21, going beyond the necessary power levels and duration for SLS objectives, ensuring the engines safety and efficiency abilities. Credit: NASA/Stennis
” The RS-25 remains among the most effective, effective, tested, and flight-proven very first stage engines worldwide,” said Johnny Heflin, SLS liquid engines manager. “When we made the choice to restart engine production, our main objective for the shift from the area shuttle to SLS was to make it at least 30% more budget friendly while increasing functional thrust from 109% to 111%. We required to re-engineer the RS-25 for Artemis objectives while keeping the basic design and efficiency.”
Four RS-25 engines power each SLS core stage, producing more than 2 million pounds of combined thrust throughout the eight-minute climb to orbit. At the end of the Space Shuttle Program, NASA and Aerojet Rocketdyne, the RS-25 lead professional, had 16 staying engines. Starting in 2015 with a series of hot fire tests on a set of shuttle-era ground test engines, the engine group adapted the existing shuttle inventory to the SLS rockets special operating requirements for its preliminary deep space objectives by adding engine nozzle insulation and establishing a new controller to replace the obsolete shuttle engine controller.
NASAs RS-25 certification engine underwent a comprehensive hot fire test on March 21, showing innovative manufacturing techniques such as 3D printing by lead professional Aerojet Rocketdyne, promising minimized expenses and faster production for future Artemis missions. Credit: NASA/Stennis
Beginning with Artemis V, the SLS rocket will feature newly produced RS-25 engines from Aerojet Rocketdynes rebooted assembly line. These brand-new engines gain from streamlined production facilities and processes, including new products.
The main combustion chamber for the engine utilizes a modern bonding procedure. With those modifications came the requirement for hot fire screening.
( Click image for complete infographic.) The RS-25 rocket engine has a long list of historical milestones. It was initially referred to as the Space Shuttle Main Engine (SSME), introducing 135 flights over the span of three years. It continues service in another historic function launching the Space Launch System (SLS) deep space rocket, which is even more effective than the shuttle. As the most high-performance, staged combustion engine worldwide, the RS-25 will burn over 700,000 gallons of super-cooled liquid hydrogen and liquid oxygen, while producing 2 million pounds of thrust to send the rocket into orbit. Aerojet Rocketdyne of Los Angeles, California, has actually updated 16 RS-25 engines, that previously flew shuttle bus missions, with new control systems and has actually tested them at higher power levels required for the very first four Artemis objectives. The company has actually started producing more recent, enhanced versions for future flights. NASA is working to land the very first female and next guy on the Moon. SLS is part of NASAs foundation for deep area exploration, in addition to NASAs Orion spacecraft, the human landing system and the Gateway in orbit around the Moon. Credit: NASA/Kevin OBrien
” The RS-25 has an amazing history of success, but its crucial to evaluate fire the re-engineered hardware to confirm brand-new styles, making lines, products, and processes when they all come together in an engine,” stated Chip Ellis, R-25 project supervisor at Stennis.
With production on the new engines in full swing, the new style has another difficulty: the series of hot fire tests to license the style for flight. Engineers plan to certify the engine through the series of 12 starts and 6,150 seconds of hot fire time, many of it happening at the prepared 111% power level. They also will be evaluated at power levels varying from 80% to 113% power to satisfy engine throttling confirmation requirements.
Find out everything you require to understand about the RS-25 Engines that assist make SLS the most effective rocket on the planet. Credit: NASA/MSFC
” This accreditation test series is the culmination of years of effort by numerous people throughout Aerojet Rocketdyne, NASA, and our providers,” added Doug Bradley, RS-25 program director at Aerojet Rocketdyne. “This certification program has had teams across the country restart assembly line, inaugurate new providers, and prove out new production techniques that minimize both the cost and cycle time for producing each engine.”
Each test has satisfied or surpassed the 500 seconds the SLS engines would run during a normal launch. A follow-on hot fire test series with a second certification engine will start this summertime and continue through the fall to collect additional information.
With Artemis, NASA will land the very first female and the first person of color on the lunar surface and establish long-term expedition and science capabilities at the Moon in preparation for human missions to Mars. SLS and NASAs Orion spacecraft, along with the human landing system and the Gateway in orbit around the Moon, are NASAs structure for deep space exploration.