A full moon is seen from the 39B launch complex at NASA’s Kennedy Space Center in Florida on June 14, 2022. The Artemis I space launch system (SLS) and the Orion spacecraft, above the mobile launcher, are ‘they were preparing for a general wet rehearsal. practice release deadlines and procedures. The first in a series of increasingly complex missions, Artemis I will test SLS and Orion as an integrated system before manned flights to the moon. Through Artemis, NASA will land the first woman and first person of color on the lunar surface, paving the way for a long-term lunar presence and using the Moon as a springboard on the way to Mars. Credit: NASA / Ben Smegelsky
The Artemis I trial ended yesterday (June 20, 2022) at 19:37 EDT (16:37 EDT) on T-29 seconds of the countdown. This test marked the first time that the team fully loaded all the rocket propulsion tanks of the space launch system and proceeded to the countdown to the terminal launch, when many critical activities occur in rapid succession.
An artistic illustration of the mobile launcher with umbilical lines installed in the tower and connected to the rocket of NASA’s space launch system and the Orion spacecraft. Credit: NASA
During the propellant loading operations in the early hours of the day, the launch controllers found a hydrogen leak in the quick disconnect that connects an umbilical from the service pole of the tail of the mobile launcher to the central stage of the rocket . The team tried to fix the leak by heating the quick disconnect and then cooling it again to align a seal, but their efforts did not solve the problem.
The launch controllers then developed a plan to mask the data associated with the leak that would trigger a hold by the ground launch sequencer, or the launch computer, in a real launch day scenario, to allow ‘ Get them as far back as possible. The time required to develop the plan required an extended retention time during the countdown activities, but they were able to resume with the last 10 minutes of the countdown, called the terminal count. During the terminal count, the crews performed a number of critical operations that must be performed for the launch, including the change of control from the ground launch sequencer to the automated launch sequencer controlled by the rocket flight software, and an important step the team wanted to take.
This second test of Artemis I began on June 18, 2022. After the launch team arrived at its stations inside the launch control center of NASA’s Kennedy Space Center in Florida, at approximately 5 p.m. EDT, to begin the wet suit rehearsal test for NASA’s Artemis. I mission. The countdown began 30 minutes later at 5:30 p.m. or 5:45 p.m., 10 minutes before the initial T-0 target at 2:40 p.m., Monday, June 20th.
During the night of June 18-19, engineers lit the Orion spacecraft and the central stage of the space launch system. The crews also set up various ground, rocket, and spacecraft systems, and conducted umbilical cord-preparing activities that connect the rocket and the spacecraft to the mobile launcher and are used to provide power, communications, coolant, and propellant.
On the morning of June 20, the launch control team began relaxation operations and resumed the countdown clock before flowing super cold liquid oxygen (LOX) into the center stage tank. The T-0 time for today’s test is now at 16:38 EDT for the first of the two terminal count runs for the wet suit rehearsal.
The process of filling the central stage tank begins with the cooling, or cooling, of the propeller lines to charge the liquid oxygen and liquid hydrogen in preparation for the tank. The equipment will slowly fill with liquid oxygen in the central stage tank and rapid filling begins shortly thereafter. The equipment will then proceed to slowly fill the liquid hydrogen tank from the basic stage followed by a quick fill.