Recall that this will be the second attempt to conduct the final tests of the main stage before the lunar rocket’s final assembly. It is good that reusable RS-25 engines from the Space Shuttle program are used as stage engines. The resource embedded in them is sufficient for many test cycles and not for one cycle within one flight. The only drawback of multiple approaches is the more and more time shift in the new lunar program “Artemis.”

The final testing of the first stage of the SLS – the Green Run test – was to occur on January 19. The test ended too quickly due to the automatic emergency operation. Retesting was postponed to February 26, but a preliminary check revealed an “incorrect” operation of one of the valves for supplying the oxidizer fuel to the RS-25 engine. The tests were postponed indefinitely.

Over the weekend, NASA engineers repaired the valve and made sure it worked. Over the next few days, specialists will conduct a new comprehensive check of the main stage systems and expect that the stage will be ready for final fire tests by the middle of this month. If everything goes well, the stage will be removed from the stand and sent to the NASA Center’s rocket assembly. Kennedy, where the second stage and the Orion spacecraft will be installed on it. Thus, the delay from the schedule will be about two months, and the unmanned launch of Orion to the Moon may take place as early as this year.