Engineers and technicians successfully completed a second countdown sequencing test on Jan. 24 inside the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida. This is one of the final tests for the SLS rocket and Orion spacecraft ahead the Artemis I mission, and brings the team one step closer to rolling to the launch pad in mid-February for the wet dress rehearsal test.
The test demonstrated the ground launch software and ground launch sequencer, which checks the health and status of the rocket sitting on the pad. The simulated launch countdown tested the responses from the Space Launch System rocket and Orion spacecraft, ensuring the sequencer operates correctly. On launch day, the ground launch sequencer hands off to the rocket and spacecraft, and an automated launch sequencer takes over control of the rocket from ground controllers around 30 seconds before launch.
Up next the team will work to complete the final program specific engineering tests for the Artemis I mission. With the countdown sequencing test complete, Exploration Ground Systems teams will continue doing final checks and closeouts of the Moon rocket in preparation for the wet dress rehearsal test next month. For wet dress rehearsal, engineers will fully load SLS with propellant, and the team on the ground will run through all the pre-launch operations to prepare for the Artemis I launch.
This 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, 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.
On Jan. 11, engineers and technicians with Exploration Ground Systems retracted and extended the Orion spacecraft crew access arm as part of ongoing work leading up to the Artemis I wet dress rehearsal targeted for late February.
The arm rotates from its retracted position and interfaces with the Space Launch System (SLS) rocket at the Orion crew hatch location to provide entry and exit for the Orion crew module during operations in the Vehicle Assembly Building and at the launch pad. On crewed Artemis missions, the access arm also provides entry and exit for astronauts. The arm retracts from the Orion spacecraft before launch.
The team continues to complete final testing and closeouts of SLS and Orion. Check back for updates on the agency Artemis blog.
Engineers and technicians continue to complete integrated tests inside the Vehicle Assembly Building at NASA’s Kennedy Space Center as part of the lead up to launch of the Artemis I mission.
On Dec. 17, the team completed a communications end-to-end test to ensure the rocket, spacecraft and ground equipment can communicate with the consoles in the launch and mission control centers. This verification of communication systems via radio frequency ensures the launch team will be able to monitor the Space Launch System (SLS) rocket and Orion spacecraft on the ground as well as during flight. The test used an antenna in the VAB, another near the pad that will cover the first few seconds of launch, as well as a more powerful antenna that uses the Tracking Data Relay Satellite and the Deep Space Network.
On Dec. 20, the Exploration Ground Systems team conducted a countdown sequencing test to demonstrate the ground launch software and ground launch sequencer, which checks for health and status of the vehicle sitting on the pad. The simulated launch countdown tested the responses from SLS and Orion, ensuring the sequencer can run without any issues. On launch day, the ground launch sequencer hands off to the rocket and spacecraft and an automated launch sequencer takes over around 30 seconds before launch. Engineers have added a second sequencing test before rollout to account for differences between the emulator and flight hardware identified during the initial test.
Last week engineers and technicians successfully removed and replaced an engine controller from one of four RS-25 engines after the team identified an issue during a power-up test of the rocket’s core stage. Engineers are now performing standard engine controller diagnostic tests and check-outs, including controller power-up and flight software load. Subsequently, the team will work to complete all remaining SLS pre-flight diagnostic tests and hardware closeouts in advance of a mid-February rollout for a wet dress rehearsal in late February. NASA will set a target launch date after a successful wet dress rehearsal test.
SLS will be the most powerful rocket in the world and is the only rocket that can send Orion, astronauts, and supplies to the Moon in a single mission. With the Artemis missions, NASA will land the first woman and the first person of color on the Moon and establish long-term exploration in preparation for missions to Mars. SLS and Orion, along with the commercial human landing system and the Gateway that will orbit the Moon, are NASA’s backbone for deep space exploration.