The flight preparations for the four engines that will power NASA’s Space Launch System (SLS) on its first integrated flight with Orion are complete and the engines are assembled and ready to be joined to the deep space rocket’s core stage. All five structures that form the massive core stage for the rocket have been built including the engine section where the RS-25 engines will be attached.
The SLS has the largest core stage ever built and includes four RS-25 engines, which previously powered NASA’s space shuttle. The RS-25 engines that are being tested and prepared for SLS were proven during the years they were responsible for propelling 135 shuttle missions, and have been upgraded for the first SLS flight. The four that will fly on Exploration Mission-1 supported a total of 21 shuttle missions.
NASA has 16 flight-proven RS-25 engines and two development engines that are being used as “workhorse” engines for testing. The liquid oxygen flight tank recently completed the first hydrostatic test for an SLS tank. The weld strength was tested by filling the tank with 200,000 gallons of water and subjecting it to pressures and forces similar to those it will experience during flight. The liquid hydrogen tank will soon undergo proof testing using gaseous nitrogen.