October 7, 2022

NASA team meets all objectives for Artemis I fueling test, despite leaks

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A critical fuel test for the Artemis I mega-moon rocket met all objectives Wednesday despite some challenges, a NASA official said. The test results will determine when the mission begins its journey around the moon and back.

“All the goals we set out to do, we were able to accomplish today,” said Charlie Blackwell Thompson, launch director of NASA’s Exploration Ground Systems Program at Kennedy Space Center in Florida.

The Space Launch System rocket and Orion spacecraft are in a safe configuration and continue to sit on the launch pad at Kennedy Space Center.

NASA engineers detected a liquid hydrogen leak during Wednesday’s test that had the “same signature” as the one that halted the Sept. 3 launch attempt. However, their troubleshooting efforts allow the team to handle the leak. After that, they “didn’t see the same leak signature, which was great,” Blackwell-Thompson said.

The team was able to completely fill the core stage with liquid oxygen and liquid hydrogen. They also completed an engine bleed test, which conditions the four engines and brings their temperature down before launch. (The mission team cleared the first Artemis I launch attempt on August 29 of a problem with a faulty sensor during bleeding.)

Next, the Artemis team fueled the rocket’s upper stage and conducted a pre-pressure test, which went “very well,” according to engineers. It was supposed to last an hour, but only took 15 minutes.

The purpose of the test was to “bring the liquid hydrogen tank to the pressure level it would experience before launch while engineers calibrate the settings for conditioning the engines at higher flow rates, as during a terminal countdown.” will be done,” according to one. Monday’s update from NASA officials. This will “enable teams to dial in the necessary settings and validate timelines before launch day, reducing schedule risk during the launch countdown.”

During the pressure test, hydrogen leakage at the 4-inch quick-disconnect line for the engine bleed was detected at slightly more than 5%, well above the 4% limit. This quick disconnect line carries the liquid hydrogen out after passing through the engines and cooling. But as hydrogen continued to flow, the leakage rate itself slowed. The team will drain all the propellant tanks and is waiting to evaluate the data from the test.

By increasing the pressure, the leak went down, which was encouraging for Blackwell Thompson and his team, he said. They will review the lessons learned from the test to see if any changes need to be made to loading procedures or timelines.

“I think we’ll take the data and we’ll see what it tells us,” he said. “I’m very encouraged by today’s Test. I couldn’t be more proud of the team and their work today.

The next launch attempt could be on Tuesday, September 27, with a 70-minute window that opens at 11:37 a.m. ET. Mission managers will meet on Sunday, Sept. 25, to discuss test results to determine a possible launch date.

The Artemis I cryogenic demonstration test began fueling at 7:30 a.m. ET Wednesday.

Artemis team members were slowly filling the rocket’s core stage with supercooled liquid hydrogen, but they stopped shortly after 10 a.m. ET when a hydrogen leak was detected. The leak is in the same area as a recently repaired quick-disconnect line, and it happened at the moment when the team first encountered problems – as the liquid hydrogen transitioned from slowly filling the rocket to rapidly filling it. was

As the team stopped the flow of liquid hydrogen, the 7% leak rate dropped. The launch team let the line warm up in hopes that when they restarted the flow of liquid hydrogen, it would restore the connection and fix the leak.

The team reduced the pressure in the storage tank and when they started flowing liquid hydrogen again, they very slowly increased the pressure.

Engineers began rapidly filling the rocket’s core stage with liquid hydrogen. While a small hydrogen leak remained, it was below the level of concern. Engineers increased the pressure and monitored the rate of leakage. They wanted to collect data to determine where the leak moved in response to pressure changes.

Since the second scrubbed launch attempt of the uncrewed Artemis I mission on Sept. 3, engineers have replaced two seals at an interface for the liquid hydrogen fuel line between the rocket and the mobile launcher, according to NASA officials. . These seals were associated with a large hydrogen leak that caused the launch attempt to be aborted.

Engineers found an indentation in the seal on the 8-inch (20-centimeter) quick-disconnect line for hydrogen, Artemis mission manager Mike Sarafin said at a NASA press conference Monday.

The indentation on the seal was less than 0.01 inch (0.3 mm), but it allowed the release of pressurized gas, which could be very dangerous given the flammability of hydrogen when mixed with air. The team believes that the dent was connected to the leak, but the test results may confirm this. They have since changed the seal.

The purpose of the cryogenic demonstration is to test seals and use an updated, “kinder and gentler” loading method of supercooled propellant, which the rocket will experience on launch day.

Jeremy Parsons, deputy manager of NASA’s Exploration Ground Systems Program, said the Orion spacecraft and rocket booster lost power during the test, and the team does not plan to enter the terminal countdown, or the final 10 countdowns before launch. Not intending to leave in minutes. Kennedy Space Center.

A gentle and gentle loading procedure is intended to minimize pressure surges and thermal spikes during pre-launch efforts.

The Artemis team is receiving daily briefings on whether or not Hurricane Fiona has an impact on whether or not the rocket stack needs to be brought back to the Vehicle Assembly Building at Kennedy Space Center, a process that could take up to three days.

If Artemis I launches on September 27, it will go on a 39-day mission and return to Earth on November 5. Another backup launch date is possible on October 2. While these launch dates are suggested by NASA, the team ultimately depends. A decision by the U.S. Space Force, which would require issuing a waiver for the launch.

The U.S. Space Force, an arm of the military, still oversees all rocket launches from the East Coast of the United States, including NASA’s Florida launch site, and the area is known as the Eastern Range.

Range personnel are tasked with ensuring that any attempted launch poses no risk to people or property.

NASA officials said the Artemis team continues to have “productive and collaborative” discussions with the Eastern Range, and NASA is sharing additional detailed information requested by Space Force for review.

“We’ll go when we’re ready,” Sarafin said. “But in terms of the reward of flying this flight, we’ve said from the beginning that this is the first in an increasingly complex series of missions, and this is a purposeful stress test of the rocket.”

The inaugural mission of the Artemis program will begin a phase of NASA space exploration that plans to land a diverse crew of astronauts on the first unexplored regions of the Moon – Artemis II and . Artemis III The missions — slated for 2024 and 2025, respectively — and eventually lead to crewed missions to Mars.

The agency released on Tuesday. An updated version of his “Moon to Mars” objectiveswhich provides a blueprint for exploring the solar system.

“We are helping to propel humanity’s global movement into deep space,” Jim Frey, NASA’s associate administrator for the Exploration Systems Development Mission Directorate, said in a statement.

“The goals will help ensure that a long-term strategy for solar system exploration can maintain consistency of purpose and weather political and financial changes.”

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