NASA’s Artemis 1 lunar mission rocket arrives at High Bay 3 from the vehicle assembly building on Saturday, July 2nd. Credit: Stephen Clark / Spaceflight Now
The new lunar rocket from NASA’s space launch system was transported from its launch pad to the vehicle assembly building at the Kennedy Space Center on Saturday for repairs, testing and final closures, approaching taking off in late summer after completing a fuel demonstration last month.
The 322-foot (98-meter) lunar rocket took off from its poles on platform 39B at 4:12 am (0812 GMT) on Saturday, about five hours late to give time for additional inspections. A diesel-powered caterpillar carrier carried the space launch system rocket down the ramp and down the rock-covered caterpillar track on the 4.2-mile (6.8-kilometer) journey back to the building. vehicle assembly.
The launcher rolled into High Bay 3 of the iconic mounting hangar around 2 pm EDT (18.00 GMT) and was secured inside the VAB approximately half an hour later.
The return of the SLS moon rocket to the vehicle assembly building makes the Artemis 1 mission one step closer to launch on a test flight around the moon. After a decade of development that cost more than $ 20 billion, the Artemis 1 mission will mark the first flight of the huge SLS moon rocket, sending a capsule of Orion’s crew heading to orbit the Moon.
The test flight will not carry astronauts, but will be the first launch of a rocket and a spacecraft to the moon from the Apollo program. If Artemis 1 flight goes according to plan, NASA intends the next SLS / Orion mission, Artemis 2, to carry a crew around the other side of the Moon and back to Earth in 2024, marking the first astronaut. trip to the moon since 1972.
Future Artemis missions will incorporate a landing of the commercial crew to transport astronauts between the Orion spacecraft in lunar orbit and the surface of the moon.
NASA’s launch team fully charged the lunar rocket with cryogenic liquid hydrogen and liquid oxygen propellants during a practice countdown on June 20, achieving an important test goal that managers wanted to complete before proceeding with the final preparations for the launch.
A number of countdown practices in April were affected by technical problems that prevented the total supply of the rocket.
The June 20 countdown trial was not without its problems. Engineers detected a hydrogen leak in a quick disconnect fitting near the bottom of the rocket’s central stage, in a line that spills excess hydrogen over the system’s hull to thermally condition the four RS-25 main engines for ignition.
The launch team overcame the problem and continued the countdown to T-minus 29 seconds, about 20 seconds before the time the engineers wanted to reach the general rehearsal. One of the final goals of the test that was not achieved on June 20 was a hot fire of hydraulic pumps that fed the steering mechanisms of the rocket’s two solid fuel propellers, which provide 80% of the steering control during the first two minutes of the launch.
NASA ground crews successfully activated the hydropower units during a separate test on June 25, paving the way for crews to prepare the rocket to return to the vehicle assembly building.
The return to the rocket hangar was supposed to begin on Thursday afternoon, but NASA delayed the move by a day to complete work on the slope of the track that led to the launch pad. Teams completed the scratching, or sifting, of the track track using heavy equipment before moving forward with the Friday night retreat.
The crawl reached a top speed of nearly 1 mile per hour during the return trip to the VAB. The combined battery of the SLS moon rocket, its mobile launch pad and the caterpillar vehicle weighs about 21.4 million pounds.
The NASA ground team briefly stopped crawling and the SLS rocket out of the VAB around noon on Saturday, giving the crew’s access arm time to the mobile launch tower to move alongside the capsule. the Orion crew at the top of the vehicle.
The access arm retracts against the mobile launch tower while in motion and cannot be extended once the rocket is inside the mounting building.
With his arm outstretched, the crawler continued to move through the vertical gate of High Bay 3. The carrier’s lifting and leveling system lowered the mobile launch pad to the pedestals within the GVA to complete the journey from the platform 39B.
The space agency has not formally set a target launch date for the first SLS rocket on the moon, but officials aim to have the launcher ready to take off on the Artemis 1 test flight in late August or early August. September, when the alignment of the moon, sun, and Earth will allow the mission to achieve all of its goals.
A release period opens on August 23 and runs until September 6. NASA has another launch period available starting Sept. 19 and extending through Oct. 4, followed by three more-two-week launch periods through the end of the year. Depending on when the Artemis 1 mission takes off, the Orion test flight could last approximately 26 days or up to 42 days. The duration of the mission depends on the location of the moon in relation to the Earth, which allows the Orion spacecraft to complete a half orbit or distant orbits of one and a half around the moon.
Launch periods are limited by a number of considerations, such as the position of the moon in its orbit around the Earth, the limits of how long the Orion spacecraft can fly in the shade without direct sunlight. to their solar matrices and the rules of re-entry and splashing. including a requirement for a daytime return to Earth to assist in recovery operations in the Pacific Ocean.
Launch windows from August 23 to September. 6 windows are published below. Release dates for August 30, August 31, and September 1 are not feasible because not all limitations of the release window for those days are met.
It launches the windows of Artemis 1 in late August and early September. Credit: NASA / Spaceflight Now
Once the rocket returns to the interior of the assembly building, workers will expand 10 sets of access platforms to reach various levels of the launch vehicle and raise an access support to reach the hydrogen line. with leaks.
Aside from the work already planned to prepare the rocket for launch, technicians will repair the leaking hydrogen connector discovered during the fuel demonstration last month. Workers will replace the Teflon seals with the quick disconnect accessories of the tail service umbilical pole, the connection that routes the cryogenic thrusters between the mobile launch pad and the SLS center stage.
Officials believe one of those stamps loosened in the 4-inch quick disconnect that began leaking during the June 20 countdown test. Phil Weber, integration manager for Artemis ’ground operations team, said last week that workers will likely also change a similar seal on a line of propellant filling and drainage larger than 8 inches as preventive measure.
Other work within the VAB will include changing an avionics box to the upper SLS stage and a software load to the higher stage computer. The ground crew will also store the final equipment inside the Orion spacecraft’s pressure cockpit and install flight batteries on the main stage, boosters and second stage, according to Cliff Lanham, Artemis 1’s flow director. NASA’s ground operations team at Kennedy.
“Then, ultimately, we want to do our flight termination system tests and, once completed, we will be able to conduct our final inspections on all volumes of the vehicle and make our closures,” Lanham said in a June 24 press. information session.
The end-of-flight system consists of pyrotechnic charges on the rocket that would be fired to destroy the vehicle if it deviated from the course and threatened populated areas.
The ground crew within the VAB will arm the flight termination system and conduct an end-to-end test, demonstrating the ability of the Space Force range security team to send a destruction command to the SLS lunar rocket. The flight termination system is only certified for 20 days after the end of the test, and the rocket should be transported back to the GVA to revalidate the destruction mechanisms.
According to Lanham, work on the SLS moon rocket inside the vehicle assembly building will take six to eight weeks.
Weber said the ground crew will make an effort to return the rocket to platform 39B after checking the flight completion system. The rocket will have to spend 10 to 14 days on the platform before the first launch attempt, and the program currently shows that the Artemis 1 team could fit into three launch attempts before the certification termination system clock expires. 20-day flight.
NASA officials are expected to set a target launch date as early as next week.
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