NASA on Sunday morning cut short a training countdown for its new mega-rocket, the Space Launch System. It’s a key part of upcoming missions to get astronauts back to the Moon, and the agency said there was a problem with the mobile launch tower.
NASA will try again on Monday.
The 322-foot-tall rocket and its Orion capsule are crucial components for NASA’s Artemis moon landing program. The system, which can launch astronauts into lunar orbit but will rely on other components to land them on the moon’s surface, is billions of dollars over budget and years behind schedule.
The weekend exercise, which NASA calls a dress rehearsal, is the last major test before the rocket launches on its first uncrewed test flight, which could take place as early as this summer. By simulating a countdown without the excitement of engines igniting and a rocket soaring into space, NASA hoped to fix equipment and procedural issues.
The rehearsal, which began Friday night, was “wet” as it was to include pumping more than 700,000 gallons of liquid oxygen and liquid hydrogen into the huge rocket’s propellant tanks.
On Saturday afternoon, severe thunderstorms passed over the launch site, with four lightning strikes protective towers around the rocket and launcher. Launch vehicle preparation work had to be halted during the storm, but after reviewing the data, NASA said there was no damage and the countdown could continue.
On Sunday, the dress rehearsal was more than three hours late. Then the shutdown happened just before the propellants began to flow. NASA said the problem was found in the mobile launcher, or the mobile tower with many systems used to manage the rocket on the ground before liftoff. The fans that create positive air pressure in the closed areas of the mobile launcher were not working. Positive pressure is necessary to prevent the buildup of hazardous gases, including those that could potentially ignite.
The fan has been running since the mobile launcher was moved to the launch site last month and continued to operate during Saturday’s thunderstorm, launch director Charlie Blackwell-Thompson told a news conference. Sunday night.
For thruster loading, the fan is switched to a different mode to blow more air. The fan ran in this mode for several hours before the problem occurred.
“We don’t think it’s lightning related,” Ms Blackwell-Thompson said.
Then a backup fan also failed, apparently for a different reason, causing the countdown to stop.
“We decided we really wanted to figure this out, given that it was the first time the vehicle had been loaded,” Ms Blackwell-Thompson said. “And we make the decision to stay down.”
On Monday, thruster loading is scheduled to begin at 7 a.m. Eastern Time, with the exercise ending in the afternoon. If the rehearsal hits further snags, another attempt could be possible on Tuesday.
The first test flight of the space launch system, Artemis 1, could take place this summer with the Orion capsule traveling around the moon and returning to Earth with astronauts on board. The second Artemis flight, scheduled for 2024, would have astronauts on board for the same trip. Artemis 3 will be the first lunar landing for astronauts since 1972. NASA has proposed a 2025 date for this crewed trip, but it could face further delays.