NASA delays tank operation of Artemis 1 ahead of afternoon wet rehearsal

Artemis I during a wet rehearsal during a tank operation on the 39-B launch pad at the Kennedy Space Center on the morning of Monday, 6/20/22.(NASA)
The extended delay for Artemis I is expected to end soon, but its afternoon wet rehearsal has been pushed back into the early evening.
Artemis Launch Control has delayed a cryogenic refueling operation at Kennedy Space Center’s 39-B launch pad because the gaseous nitrogen valve in the backup system did not close, according to NASA spokesman Derrol Nail. .
Nitrogen valves are critical for a variety of purposes, including preventing the build-up of harmful gases and keeping avionics in engine sections dry.Nail said the problem appeared to stem from a valve controller in the backup system failing to respond.The automated and manual tests went well, Nail said, and the redundant controller has now been replaced as the primary controller, which is now the secondary controller tested on Monday.
Crews were configuring the launch controller for cryogenic refueling while the controller was being tested.At present, the tank operation is undergoing rapid filling of supercooled liquid hydrogen and liquid oxygen.The combined tank holds 730,000 gallons of both fluids.
Valve issues have pushed Monday’s wet rehearsal to a target testing window starting at 4:30pm Initially, Monday’s rehearsal opened at 2:40pm The window was redone, starting Saturday night with staff before testing The climax of testing at the station is expected to be completed in about 48 hours on Monday afternoon.
At about 2:15 p.m., Nail said, a small fire was spotted in the grass near the launch pad.The team filling the start-up core stage liquid hydrogen tanks found a hydrogen leak in the engine’s flare stack, which may have started the fire during the fuel disconnect.Believe this is not a big problem, the team is keeping the fire burning, believing it will burn itself once it reaches the dirt road.
Monday’s test will include a number of operations such as simulating countdowns, refueling and discharging fuel to the 5.75 million-pound, 322-foot-tall Space Launch System, a combination of the Orion capsule and mobile launcher.Launch Pad 39-B.
Artemis’ hardware first made its way to the launch pad last March, but a series of pressure and valve problems eliminated the previous three runs during wet rehearsal, forcing NASA to return it to the Vehicle Assembly Building to fix the problem.
Once the issues are resolved, NASA hopes to complete the test and possibly set a launch date in August, with the first opportunity during the July 26-August window.After ten is a potential window that runs from August 23 to September.6, September 20-October.4. October 17-31, November 12-27 and December 9-23.Each window has only specific days during which the Earth and Moon are properly positioned for the planned mission.