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NASA marked a milestone September 30 in its plans for future missions to the Moon and possibly Mars with the completion of a series of single-engine RS-25 Retrofit-2 tests at the Stennis Space Center near Bay St Louis, Mississippi.
A full-span burning fire of RS-25 Development Engine # 0528 on the A-1 test stand at Stennis resulted in a series of seven tests to support the development and production of new engines for the Space Launch rocket System (SLS) of the agency in the future missions.
“This series of successful tests for the space launch system’s RS-25 engine brings us one step closer to manufacturing the first new set of engines for future Artemis missions to the moon,” said Johnny Heflin, director of the SLS Liquid Engines Office. at NASA’s Marshall. Space flight center at Huntsville, Alabama. âWe test engine parts made with advanced manufacturing techniques that can reduce the cost of each engine by more than 30% while maintaining the reliability and high performance of the RS-25 engine. “
During the burning fire on September 30, operators fired the RS-25 Development Engine # 0528, used for each of the seven tests in the series, for more than eight minutes (500 seconds), the same time required during an actual launch.
The series of tests provided valuable information to Aerojet Rocketdyne, prime contractor for SLS engines, as it produces engines for use after the Artemis IV mission to the moon. Operators collected hot fire data to demonstrate and verify various engine capabilities, and to evaluate new engine components manufactured with advanced and economical technologies and reduce operational risk.
Components tested included a 3D printed pogo accumulator to damp pressure oscillations that can cause flight instability and a main combustion chamber fabricated using a hot isostatic pressure (HIP) bonding technique. These components are important early milestones in NASA and Aerojet Rocketdyne’s efforts to maximize advanced manufacturing methods to dramatically reduce the cost and time required to build new RS-25 engines.
The September 30 test was delayed from its original date due to the impacts of Hurricane Ida, which hit the Gulf Coast region on August 29. The storm initially affected propellant deliveries to the center, necessitating a delay as suppliers recovered to full capacity.
âI am proud to see how the test team and our propellant suppliers weathered the impacts of Hurricane Ida to allow us to start testing RS-25 again,â said Chip Ellis, Stennis RS project manager. -25. âWith each test, we learn more and more about the RS-25 engine and how it works. And it’s exciting to know that what we’re doing contributes to the safety of the astronauts who will be flying SLS. “
Four RS-25 engines, along with a pair of solid rock thrusters, will help propel SLS to launch. Pulling simultaneously, the engines will generate a combined thrust of 1.6 million pounds on takeoff and 2 million pounds on the climb.
Previous RS-25 tests at Stennis began on January 9, 2015 and ended on April 4, 2019. During this period, NASA completed acceptance testing of the old main space shuttle engines that will help propel the first four SLS missions, carried out development and airworthiness tests. for 16 new controllers (plus one aftermarket) for use on traditional RS-25 engines, and demonstrated the ability of RS-25 engines to operate at the higher power level required to launch the super heavy SLS rocket.
The first hot fire in the most recent series took place on January 28, 2021. During the seven-part test series, which coincided with the Green Run tests of the main stage SLS in Stennis, the development engine No. 0528 suffered 3,650 seconds of scorching fire. The program consisted of six hot fire trials of over eight minutes (500 seconds) and one hot fire of just under 11 minutes (650 seconds). A full duration test refers to the amount of time the engine must turn on during an actual launch in order to propel SLS into orbit. Longer lasting hot fires are conducted to test the limits of engine performance.
The Retrofit-2 test series followed major maintenance and upgrade projects on the A-1 test bench, including the installation of a newly designed thrust vector control system and manufactured by NASA on the structure that allows operators to test the RS-25. motors, moving them on a tight circular axis. The gimbal is a critical capability that ensures that SLS can maintain an appropriate flight path.
Operators are expected to begin a series of Retrofit-3 follow-up trials, using RS-25 development engine # 0525, on the A-1 test bed later this fall. The new series will continue to collect data for the production of new engines.
NASA is building SLS as the most powerful rocket in the world. With Artemis, NASA will land the first woman and the first person of color on the lunar surface and establish long-term exploration on the Moon for human missions to Mars. The SLS and Orion spacecraft, along with the Commercial Human Landing System and Moon Orbiting Gateway, are NASA’s backbone for deep space exploration. The agency is working on launching the Artemis I unmanned flight test in the coming months, which will pave the way for future missions.
RS-25 tests at Stennis are being conducted by a combined team of operators from NASA, Aerojet Rocketdyne and Syncom Space Services. Syncom Space Services is the prime contractor for Stennis’ facilities and operations.
SSC-20210930-s00218 – RS-25 Hot Fire Test Cut Line: NASA conducts a full duration RS-25 hot fire test on test stand A-1 at Stennis Space Center on September 30 . The more than 8-minute hot fire marked the final test of a Retrofit-2 series to support the development and production of new engines for the agency’s space launch system.
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