After months of testing, debugging, and repairs, engineers fueled the Space Launch System moon rocket for Monday’s launch on NASA’s long-awaited Artemis 1 test flight, which will carry an unpiloted Orion crew capsule on a 42-day trek to the moon and back. Despite this, management was compelled to call a halt to the countdown after overcoming a weather delay and a brief warning of a hydrogen leak. The problem was with one of the rocket’s main engines’ cooling.
Bill Nelson, the administrator of NASA, remarked, “We don’t launch until it’s right. “It serves as a good illustration of how intricate this machine and system are and how they all need to function. The candle should not be lit until it is prepared to burn.” For the more than 25,000 NASA employees, dignitaries, and other guests who arrived at the Kennedy Space Center to see the historic launch, as well as for the tens of thousands of locals and visitors who lined the streets and beaches, it was a painful letdown.
A large number of engineers and technicians who had worked for months to prepare the enormous moon rocket for the launch were equally disappointed. It was not to be, however. Nelson said, “This is simply a part of the space industry, and it’s part of, specifically, a test mission. “We are putting this rocket and the spaceship through stress and testing in ways that you would never do with a human on board. A test flight is conducted for that reason.”
In spite of this, NASA was taking no risks with the $4.1 billion rocket, the most powerful ever created for a civilian space agency and the key to its aspirations to send men back to the moon in the next three years as part of the Artemis program. At 8:35 a.m. EDT, two minutes after the two-hour launch window opened, Launch Director Charlie Blackwell-Thompson halted the countdown after many efforts to fix the hydrogen cooling problem.
The next chance to launch is at 12:48 p.m. on Friday, supposing that the issues that arose on Monday can be fixed in time and that an extra fuelling test is not necessary. After then, on September 5 at 5:12 p.m., there is only one more chance due to the Earth and moon’s ever-changing locations, after which the rocket would have to be removed from the launch pad and brought back to the famous Vehicle Assembly Building for maintenance.
The launch would most likely be delayed until late September or, more likely, October in that scenario. The data will be analyzed by engineers to determine what needs fixing or adjusting, but no action will be taken until that period has passed.
Nelson assured the public that the launch crew will “figure out what happened, repair it, and take us into the skies.” The purpose of the Artemis 1 test flight is to confirm that the rocket can successfully launch Orion spacecraft into Earth orbit and ultimately onto the moon. Engineers will also test the crew ship’s many systems in the depths of space and ensure that its heat shield can shelter people from the 5,000°F heat of re-entry.
In 2024, NASA intends to deploy four people on a looping around-the-moon voyage to follow the unmanned Artemis 1 mission. This will pave the way for the first astronaut landing in over 50 years when the first woman and the following man touch down on the surface in 2025 or 2026. However, NASA must first demonstrate that the rocket and capsule will function as intended, and this process starts with the unmanned Artemis 1 test flight.
NASA’s SLS rocket is the most powerful ever constructed, with a height of 322 feet, a weight of 5.7 million pounds when filled with fuel, and a thrust of 8.8 million pounds during liftoff—15% greater than NASA’s iconic Saturn 5, the current record holder.
When offshore storms with rain and lightning approached within approximately six miles of launch complex 39B late Sunday night, NASA safety regulations were broken. The countdown had started on Saturday and was going well up to that point.
The six-hour fuelling operation eventually began at 1:14 a.m. after a delay of 55 minutes when engineers, operating remotely, started putting 730,000 gallons of supercold liquid oxygen and hydrogen fuel into the SLS core stage, making room for a further 22,000 gallons to be fed into the upper stage.
A leak in the system was discovered when sensors discovered higher-than-allowable amounts of hydrogen in a casing surrounding an umbilical that distributes propellants to the base of the core stage during a switch from “slow fill” to 10 times quicker rate.
Fast fill was resumed after switching back to slow fill and allowing temperatures to balance throughout the plumbing, and this time there were no problems. Then a new problem emerged. At the point when the hydrogen tank was at capacity, propellants were sent to the four RS-25 engines located at the bottom of the core stage in order to prepare them for the very low temperatures they would encounter at the high flow rates required for ignition.
Despite the fact that engine No. 3 initially failed to “see” the appropriate flow, NASA stated that three of the engines were being adequately prepared. Additional troubleshooting followed, including raising the line’s pressure, but it was ineffective.
Prior to Monday’s attempt, NASA conducted four practice countdowns and fuelling tests, all of which had issues. A leak appeared in a 4-inch quick-disconnect connection on June 20 during the last test, which sent hydrogen to the engines for cooling.
The launch of #Artemis I is no longer happening today as teams work through an issue with an engine bleed. Teams will continue to gather data, and we will keep you posted on the timing of the next launch attempt. https://t.co/tQ0lp6Ruhv pic.twitter.com/u6Uiim2mom
— NASA (@NASA) August 29, 2022
Back at the Vehicle Assembly Building, the fitting was fixed, but the job was completed in normal surroundings. Normal cryogenic conditions, which didn’t exist until Monday, are the only circumstances in which hydrogen leaks manifest. This time, there were no signs of any new leaks, and the source of engine No. 3’s cooling issue was not immediately apparent.
The rocket’s core stage was also discovered to have an odd line of frost on its outside, which may have been a sign of a leak. As it turned out, though, the frost was due to a tiny stress fracture in the insulation of the tank and was not an issue for launch. Blackwell-Thompson halted the countdown when it became clear that the hydrogen problems couldn’t be fixed in time for the launch window to close.
Source: CBS News