Due to a valve issue on ground equipment, NASA's second attempt to fuel its Artemis 1 moon mission megarocket struck another roadblock on Monday (April 4).
NASA had to cancel the Artemis 1 test after fueling began on Monday due to a jammed vent valve high up on the movable launcher structure supporting the Space Launch System rocket on the Artemis 1 at NASA's Kennedy Space Center's Launch Pad 39B, according to agency officials. During fueling, the valve is used to alleviate pressure from the rocket's core stage.
"Due [to] the vent valve issue, the launch director has called off the test for the day," Jeremy Parsons, NASA's deputy director for ground systems, wrote in a Twitter update. "The team is preparing to offload LOX (liquid oxygen) and will begin discussing how quickly the vehicle can be turned around for the next attempt."
NASA attempted to fuel the Artemis 1 moon rocket on Sunday (April 3) but was forced to abandon the operation before propellant loading could begin owing to an issue with pressurization on the mobile launcher, which keeps hazardous gases out of enclosed compartments where technicians operate. Before shutting down for the day on Monday, personnel had loaded around half of the liquid oxygen required for the fueling test, Parsons reported on Twitter.
The goal of Monday's test was to simulate a launch countdown that would terminate at 2:40 p.m. EDT, however problems with the rocket's nitrogen gas source caused that work to be halted. NASA was aiming for a simulated launch time of 6:02 p.m. EDT once that issue was resolved prior to the stopped valve, which necessitated the scrub.
According to Parsons, the vent valve was located on the 160-foot (49-meter) level of the mobile launcher, which functions as both a gantry and a launch platform for the SLS. The fault, according to NASA officials, happened in a panel that regulates the valve, preventing workers from opening it.
Monday's fuelling attempt was NASA's second attempt to fill the core stage of Artemis 1's 322-foot-tall (98-meter) SLS rocket with 700,000 gallons (2.6 million liters) of super-chilled liquid oxygen and liquid hydrogen propellant in a "wet dress rehearsal," which began April 1.
It is unknown if NASA will be able to recycle for a third fueling attempt on Tuesday (April 5) or if it will be forced to stand down to replenish propellant supplies and give its pad operators and launch controllers time to recover.
