(NASA) – Over the last week, engineers and technicians successfully completed an engineering test series of the Space Launch System (SLS) rocket core stage inside the Vehicle Assembly Building at NASA’s Kennedy Space Center as part of the integrated testing before launch.

After replacing and testing one of four RS-25 engine controllers, (video above) the team conducted several tests to ensure the massive core stage is ready to roll to the launch pad for the wet dress rehearsal ahead of the Artemis I launch. Engineers and technicians tested communication between the flight computers and other core stage systems and slightly moved the engines to practice the gimbaling they will experience during flight.

All four engine controllers were powered up and performed as expected as part of the Artemis I Core Stage engineering tests. Following the power up, engineers successfully performed diagnostic tests on each controller.

Up next, the team will conduct a second countdown sequencing test to demonstrate the ground launch software and ground launch sequencer, which checks for health and status of the vehicle while at the pad. The simulated launch countdown tests the responses from SLS and the Orion spacecraft, ensuring the sequencer can run without any issues. After the countdown test and final closeouts are complete, SLS and Orion will head to the launch pad for the first time to complete the wet dress rehearsal test.