NASA Eyes Next Wet Dress Rehearsal for Artemis II

NASA is targeting Thursday, Feb. 19, as the tanking day for the second wet dress rehearsal ahead of the agency’s Artemis II test flight.

Over the weekend, teams replaced a filter in ground support equipment that was suspected of reducing the flow of liquid hydrogen during a Feb. 12 partial fueling test. The test provided enough data to allow engineers to plan toward a second wet dress rehearsal this week. Engineers have reconnected the line with the new filter and are reestablishing proper environmental conditions.

The wet dress rehearsal will run the launch team as well as supporting teams through a full range of operations, including loading cryogenic liquid propellant into the SLS (Space Launch System) rocket’s tanks, conducting a launch countdown, demonstrating the ability to recycle the countdown clock, and draining the tanks to practice scrub procedures. 

Launch controllers will arrive to their consoles in the Launch Control Center at NASA’s Kennedy Space Center in Florida at 6:40 p.m. EST on Feb. 17 to begin the nearly 50-hour countdown. The simulated launch time is 8:30 p.m., Feb. 19, with a four-hour window for the test. While the Artemis II crew is not participating in the test, a team of personnel will go to the launch pad to practice Orion closeout operations, including closing the spacecraft’s hatches.

During the rehearsal, the team will execute a detailed countdown sequence. Operators will conduct two runs of the last ten minutes of the countdown, known as terminal count. They will pause at T-1 minute and 30 seconds for up to three minutes, then resume until T-33 seconds before launch and pause again. After that, they will recycle the clock back to T-10 minutes and conduct a second terminal countdown to just inside of T-30 seconds before ending the sequence. This process simulates real-world conditions, including scenarios where a launch might be scrubbed due to technical or weather issues.

While NASA will not set a formal launch date until after a successful rehearsal and data reviews, the agency has been evaluating in recent weeks if the there are additional days that would be suitable for launch and found an extra opportunity the first week of March. However, managers have determined March 6 is the earliest opportunity for launch that allows for a second wet dress rehearsal, sufficient time for data review, and time to transition the launch pad, rocket, and spacecraft to launch operations.

A 24/7 live stream of the rocket at the pad remains online. During the upcoming wet dress rehearsal, NASA will provide a separate feed with additional camera views on the day of fueling and share updates via the agency’s Artemis blog.