NASA’s wet dress rehearsal concluded early this morning which included some issues during the tanking of the rocket. NASA has scheduled a media conference today to discuss the results but has already made the decision to push the launch to the March window.
In an update early this morning NASA said of the test:
During tanking, engineers spent several hours troubleshooting a liquid hydrogen leak in an interface used to route the cryogenic propellant into the rocket’s core stage, putting them behind in the countdown. Attempts to resolve the issue involved stopping the flow of liquid hydrogen into the core stage, allowing the interface to warm up for the seals to reseat, and adjusting the flow of the propellant.
Teams successfully filled all tanks in both the core stage and interim cryogenic propulsion stage before a team of five was sent to the launch pad to finish Orion closeout operations. Engineers conducted a first run at terminal countdown operations during the test, counting down to approximately 5 minutes left in the countdown, before the ground launch sequencer automatically stopped the countdown due to a spike in the liquid hydrogen leak rate.
In addition to the liquid hydrogen leak, a valve associated with Orion crew module hatch pressurization, which recently was replaced, required retorquing, and closeout operations took longer than planned. Cold weather that affected several cameras and other equipment didn’t impede wet dress rehearsal activities, but would have required additional attention on launch day. Finally, engineers have been troubleshooting dropouts of audio communication channels across ground teams in the past few weeks leading up to the test. Several dropouts reoccurred during the wet dress rehearsal.
The crew had not travelled from NASA’s Johnson Space Center in Houston to the Kennedy Space Center in Florida yet. They will now stay in Houston but will exit quarantine and resume training. Once a new launch date is set the crew will enter quarantine again approximately two weeks before launch. The first launch window in March is the 6th at 8:29 p.m. EST.
Once the date is set for launch NASA will conduct another wet dress rehearsal and simulate the countdown.
We’ll provide a further update after NASA’s news conference today.