Teams Continue to Review Options for Next Attempt, Prepare to Replace Seal

NASA's engineers discovered problems with one of the gas lines as fuel was actively being loaded. troubleshooting efforts were halted after a liquid hydrogen seam which is used to keep the rocket's core-stage engines cold had failed. Image | NASA | Wikipedia

By Matt Pepple, SJ Correspondent
September 02, 2022 06:30 pm UTC
Modified: 2022-09-07 06:30 pm

ALABAMA - NASA made a second attempt to launch the Artemis 1 SLS on Saturday, but a hydrogen fuel leak was detected in the gas line that perplexed technicians. Several attempts were made to fix the leak before Charlie Blackwell-Thompson, the launch director determined at 11:17 am that it was time to cancel the liftoff, According to the New York Times.

Lightning had previously struck the launch towers at the Kennedy Space Center last Saturday, though officials said that the lightning was "low magnitude" and would not likely affect the launch in any way.

The Orion enclosure and the remote-controlled SLS (space launch system) were scheduled for liftoff on a trial space flight to the moon, christened Artemis 1, but engine issues foiled the greatly-expected launch.

NASA's engineers discovered problems with one of the gas lines as fuel was actively being loaded. Troubleshooting efforts were halted after a liquid hydrogen seam which is used to keep the rocket's core-stage engines cold had failed, according to NBC.

The 4-core stage rocket engines require being chilled to cryogenic temperatures before liftoff in order to prevent a systems shock when super cold accelerant hits the higher temperatures when the engine is fired up.

According to ABC News, NASA representatives said on Monday that engine 3 didn't successfully cool down to a temperature of 500 degrees Rankine (40.3 Fahrenheit) which is required for a successful liftoff.

The manager of the Space Launch System Program at Marshall Space Flight Center, John Honeycutt thinks the issue might have been caused by a faulty sensor, rather than the engine not cooling properly.

ABC quoted Honeycutt as saying, “I think we've got enough data to put the story together, but we've still got to go put the pieces together”.

NASA will need to reschedule the launch for a different day. There is a chance the rescheduled launch might happen on Monday or Tuesday, but if the division is not capable of proceeding, it will need to hold off on the launch until September or October. The chief of NASA, Bill Nelson stated on Monday that the division will not complete the trial until it was safe to do so.

Bill Nelson said, “When you're dealing in a high-risk business — and spaceflight is risky — that's what you do," he said. "You buy down that risk. You make it as safe as possible,” as quoted by NBC.

Representatives for NASA stated that the spacecraft and rocket were presently in a stable, safe condition," and that technicians intend to carry on collecting information out of the space vehicle, on the launching platform.

The occurrence Monday was supposed to be the initial flight of the 322-foot-tall SLS, something NASA has touted as “the most powerful rocket in the world.” The preliminary launch is tailored to examine both the Orion spacecraft and the SLS rocket system ahead of sending any astronauts to the surface of the Moon.

The Artemis I has been held up for over 10 years due to research by Nasa. Nasa's research has led to building a new mega-rocket that goes "above and beyond" the capacities of the Saturn V, utilized during the Apollo mission era during the 60s & 70s. The Artemis project has been facing harsh criticism for being behind schedule, and for costing billions of dollars more than previously budgeted.

NASA Inspector General Paul Martin met with the House Science Committee for an inquiry earlier in 2022. He said that NASA is expected to spend $93 billion on the Artemis project which spans the time frame from 2022 to 2025.

Many spacecraft do not make it to space without a list of delays and failures. Another example was the initial launch of SpaceX crewed by NASA astronauts. It was to be the first time a launch had occurred since the departure of the Space Shuttle program, and the launch of the SpaceX mission had entered the last minutes of the countdown before being postponed due to bad weather. It was successfully launched 3 days later.

Hydrogen leaks have been a common denominator for grounding spaceflights in the past. Hydrogen is a potent rocket propellant. Because hydrogen is the smallest of particles, it is very troublesome to operate with, often spilling through the smallest of spaces.

Many times ruptures do not reveal themselves until the gas lines are frozen to ultracold temperatures of -423 degrees Fahrenheit, which the temperature at which hydrogen reverts to a liquid form. There are no other methods to detect this kind of spill other than during the countdown sequence when hydrogen begins streaming into the rocket.

The Artemis Project was chosen to be named after the Greek goddess Artemis, who is the twin sister of Apollo in Greek mythology. NASA foresees regulated missions to the lunar surface to lay the foundation for a base camp that could serve as a “jumping-off point” for trips to Mars.

Representatives for NASA say that astronauts could go back to the Moon as soon as the year 2025.

Update - Teams Continue to Review Options for Next Attempt, Prepare to Replace Seal

NASA - After standing down on the Artemis I launch attempt Saturday, Sept. 3 due to a hydrogen leak, teams have decided to replace the seal on an interface, called the quick disconnect, between the liquid hydrogen fuel feed line on the mobile launcher and the Space Launch System (SLS) rocket while at the launch pad.

Performing the work at the pad requires technicians to set up an enclosure around the work area to protect the hardware from the weather and other environmental conditions, but enables engineers to test the repair under cryogenic, or supercold, conditions. Performing the work at the pad also allows teams to gather as much data as possible to understand the cause of the issue. Teams may return the rocket to the Vehicle Assembly Building (VAB) to perform additional work that does not require use of the cryogenic facilities available only at the pad.

To meet the current requirement by the Eastern Range for the certification on the flight termination system, NASA would need to roll the rocket and spacecraft back to the VAB before the next launch attempt to reset the system’s batteries.

Additionally, teams will also check plate coverings on other umbilical interfaces to ensure there are no leaks present at those locations. With seven main umbilical lines, each line may have multiple connection points.

Statement By NASA On September 3rd:

After standing down on today’s Artemis I launch attempt when engineers could not overcome a hydrogen leak in a quick disconnect, an interface between the liquid hydrogen fuel feed line and the Space Launch System (SLS) rocket, mission managers met and decided they will forego additional launch attempts in early September.

Over the next several days, teams will establish access to the area of the leak at Launch Pad 39B, and in parallel conduct a schedule assessment to provide additional data that will inform a decision on whether to perform work to replace a seal either at the pad, where it can be tested under cryogenic conditions, or inside the Vehicle Assembly Building.

To meet the requirement by the Eastern Range for the certification on the flight termination system, currently set at 25 days, NASA will need to roll the rocket and spacecraft back to the VAB before the next launch attempt to reset the system’s batteries. The flight termination system is required on all rockets to protect public safety.

During today’s launch attempt, engineers saw a leak in a cavity between the ground side and rocket side plates surrounding an 8-inch line used to fill and drain liquid hydrogen from the SLS rocket. Three attempts at reseating the seal were unsuccessful. While in an early phase of hydrogen loading operations called chilldown, when launch controllers cool down the lines and propulsion system prior to flowing super cold liquid hydrogen into the rocket’s tank at minus 423 degrees F, an inadvertent command was sent that temporarily raised the pressure in the system. While the rocket remained safe and it is too early to tell whether the bump in pressurization contributed to the cause of the leaky seal, engineers are examining the issue.

Because of the complex orbital mechanics involved in launching to the Moon, NASA would have had to launch Artemis I by Tuesday, Sept. 6 as part of the current launch period.