NASA’s next-generation Moon rocket is all gassed up and has nowhere to go today. Today, the Space Launch System (SLS) was filled with liquid oxygen and liquid hydrogen fuel for an hours-long test of its troubled fuelling system.
After a hydrogen leak halted the rocket’s second launch attempt and the Artemis I mission on September 3rd, NASA was testing a “kinder, gentler” fuelling process. According to NASA, the revised processes were “intended to transition temperature and pressures gently during refueling to lessen the possibility of breaches that may be induced by abrupt changes in temperature or pressure.”
After the test, Charlie Blackwell-Thompson, launch director for NASA’s Artemis program, remarked, “I am quite encouraged.” She refused to predict the schedule of the next launch attempt, stating that the team needed to review today’s data to determine whether the timeframe needed to be adjusted. “I try not to get ahead of the statistics,” she continued.
Without actually launching the rocket, the test was planned to recreate practically everything the crew would go through throughout the fuelling procedure on launch day. The equipment was subjected to the same extreme cold temperatures as it would encounter during normal fuelling. Engineers discovered a leak in a section of the fuelling system that links to the rocket, known as a “fast detach umbilical line,” while the rocket was being filled with liquid hydrogen. The crew opted to warm up that component of the system to see whether the fast disconnect would recalibrate and prevent the leak from worsening. The treatment seemed to be effective; it did not halt the leak, but it did limit it to a “manageable” level.
The liquid hydrogen leak remains manageable during the Artemis I cryogenic demonstration test. Teams warmed up the quick disconnect umbilical line and the leak then maxed out at 3.4%, which is within the acceptable range to continue.
— NASA's Exploration Ground Systems (@NASAGroundSys) September 21, 2022
According to NASA, all test goals were completed, clearing the path for another launch attempt. But when it will happen is still unknown. NASA has set a preliminary launch date of next Tuesday, September 27th, with a backup date of October 2nd.
But there are a few details that must be worked out before the rocket can ascend to the sky. In addition to engineers from the launch team reviewing today’s data to determine if any adjustments to the fuelling method are needed, NASA must also get permission from the Space Force to launch.
The Space Force will be in charge of safety in the region where NASA will launch. They need rockets to be equipped with a mechanism that allows them to destroy the rocket if anything goes wrong. When the rocket rolled out to the pad in August, the flight termination mechanism was approved for 20 days. NASA did get a brief extension of the certification to 25 days before the second launch attempt, but the rocket has already remained at the launchpad for 35 days. We’ll have to wait and see what the Space Force and NASA decide in the following days.
