Inside the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida, technicians continue to prepare the Space Launch System rocket and Orion spacecraft for Artemis I.
During work to repair the source of a hydrogen leak, engineers identified a loose fitting on the inside wall of the rocket’s engine section, where the quick disconnect for the liquid hydrogen umbilical attaches. The component, called a “collet,” is a fist-sized ring that guides the quick disconnect during assembly operations. Teams will repair the collet by entering the engine section in parallel with other planned work for launch preparations. Technicians have replaced the seals on the quick disconnect of the tail service mast umbilical and will reattach the umbilical plate once the loose collet is addressed.
NASA continues to target the late August launch period and will identify a specific target launch date after engineers have examined the collet.
Technicians continue work associated with battery activations, and plan to turn on the core stage batteries this weekend, before they are installed on the rocket. Next up, teams will start the flight termination systems operations, which include removing the core stage and booster safe and arm devices for calibration and removing and replacing the command receiver decoders with the flight units. The safe and arm devices are a manual mechanism that put the flight termination system in either a “safe” or “arm” configuration while the command receiver decoders receive and decode the command on the rocket if the system is activated.
Meanwhile on the Orion spacecraft, teams installed a technology demonstration that will test digital assistance and video collaboration in deep space. Engineers are also conducting powered testing on the crew module and European service module heaters and sensors.
Since the Space Launch System (SLS) and Orion arrived back at the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida on July 2, teams extended the access platforms surrounding the rocket and spacecraft to perform repairs and conduct final operations before returning to launch pad 39B for the Artemis I mission.
Technicians are working to inspect, fix, and check out equipment associated with a seal on the quick disconnect of the tail service mast umbilical that was identified as the source of a hydrogen leak during the wet dress rehearsal test that ended June 20. Engineers have disconnected the umbilical and are in the process of examining the area where they will replace two seals on the quick disconnect hardware. Working in tandem with those repairs, engineers also completed the last remaining engineering test that is part of the integrated testing operations in the VAB.
Teams also performed additional planned work on aspects of the rocket and spacecraft. Engineers swapped out a computer on the Interim Cryogenic Propulsion Stage called the Inertial Navigation and Control Assembly unit that was used during wet dress rehearsal activities with the one that will be used for flight and will test the unit next week. The newly installed flight unit includes freshly calibrated inertial navigation sensors and updated software to guide and navigate the upper stage during flight.
Technicians also activated several batteries for the rocket elements, including for the solid rocket boosters and the ICPS. The batteries on the core stage will be activated in the coming weeks, and all the batteries will then be installed. The batteries provide power for the rocket elements during the final portion of the countdown on launch day and through ascent.
Engineers also charged the batteries for the secondary payloads located on the Orion stage adapter and will work to install payloads inside the Orion spacecraft in the coming weeks.
At approximately 2:30 p.m. ET, NASA’s Space Launch System (SLS) rocket and Orion spacecraft for the Artemis I mission were firmly secured inside the Vehicle Assembly Building (VAB) at Kennedy Space Center after a four-mile journey from launch pad 39B that began at 4:12 a.m. ET Saturday, July 2.
Over the next several days, the team will extend work platforms to allow access to SLS and Orion. In the coming weeks, teams will replace a seal on the quick disconnect of the tail service mast umbilical and perform additional checkouts and activities before returning to the pad for launch.
At approximately 4:12 a.m. ET today, NASA’s Artemis I Moon rocket atop the crawler-transporter left launch pad 39B and began its 4-mile trek to the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida.
Once inside the VAB, teams will replace a seal on the quick disconnect of the tail service mast umbilical to address a liquid hydrogen leak detected during the wet dress rehearsal, along with planned forward work as the Space Launch System and Orion spacecraft are readied for launch.
Watch a live stream of the rocket arriving at VAB on the Kennedy Newsroom YouTube channel and check back here for updates.
Teams have rescheduled the return of the Space Launch System rocket and Orion spacecraft to the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center to Friday, July 1 due a concern with the condition of the crawlerway that leads from Launch Pad 39B to the VAB. First motion is now planned for 6 p.m. EDT.
This afternoon, teams conducted a series of conditioning efforts driving the massive transporter up and down the slope leading to the launch pad. The inclined pathway must be precisely level with an even distribution of the rocks that make up the crawlerway in order to support the load of the mobile launcher and rocket that it will carry.
Teams will continue grating, or sifting, the crawlerway overnight and the rocket and spacecraft remain in a safe configuration.
NASA will roll the Space Launch System rocket and Orion spacecraft for the Artemis I mission from launch pad 39B to the Vehicle Assembly Building (VAB) at the agency’s Kennedy Space Center in Florida beginning Thursday, June 30.
First motion for the rocket and spacecraft atop the mobile launcher is expected to occur at 8 p.m. EDT today. The 4-mile trek atop the crawler transporter from the launch pad to the VAB will take approximately 8-12 hours. The journey previously was expected to begin just after midnight on July 1 but was moved up by several hours due to forecasted weather in the area. Teams will continue monitoring weather in the area and the start of the roll is subject to change.
Teams completed the wet dress rehearsal test campaign for Artemis I on June 20 and have configured the rocket and spacecraft for return to the VAB. Once there, teams will replace a seal on the quick disconnect of the tail service mast umbilical to address a liquid hydrogen leak detected during the rehearsal along with final servicing and checkouts. NASA plans to return the mega Moon rocket to the pad for launch in late August and will set a specific target launch date after replacing hardware associated with the leak.
A live feed of the rocket’s arrival to the VAB will be available on the KSC Newsroom YouTube Channel.
Over the weekend, teams successfully conducted a test of the thrust vector control system on each of the twin solid rocket boosters of the Space Launch System for Artemis I while the rocket remains at Launch Pad 39B. The test was a follow-on to the wet dress rehearsal test campaign, which was completed last week.
During the test, engineers activated the booster hydraulic power units (HPU), which are hydrazine-powered turbines attached to hydraulic pumps that provide pressure to move the hydraulic actuators that gimbal the booster nozzles. The test verified the normal startup, operations, and shutdown of a fully integrated thrust vector control system, which controls the movement of the nozzles on each of the boosters during ascent. It also verified the rocket’s avionics system using both flight and ground software for the first time. The boosters were not ignited during the test.
The test was part of the objectives that were not completed during the wet dress rehearsal demonstration, as the rehearsal test ended at T-29 seconds during the terminal countdown. During launch, the automated launch sequencer gives the command to activate the HPUs at T-28 seconds.
Teams will drain the hydrazine from the boosters and are in the process of configuring the rocket and Orion spacecraft for their return to the Vehicle Assembly Building (VAB) at the end of the week. Once there, teams will replace a seal on the quick disconnect of the tail service mast umbilical to address a liquid hydrogen leak detected during the rehearsal. NASA plans to return the mega Moon rocket to the pad for launch in late August and will set a specific target launch date after replacing hardware associated with the leak.
A live feed of the rocket departing the launch pad and arrival at VAB will be available on the KSC Newsroom YouTube Channel.
The Artemis I wet dress rehearsal ended today at 7:37 p.m. EDT at T-29 seconds in the countdown. Today’s test marked the first time the team fully loaded all the Space Launch System rocket’s propellant tanks and proceeded into the terminal launch countdown, when many critical activities occur in rapid succession.
During propellant loading operations earlier in the day, launch controllers encountered a hydrogen leak in the quick disconnect that attaches an umbilical from the tail service mast on the mobile launcher to the rocket’s core stage. The team attempted to fix the leak by warming the quick disconnect and then chilling it back down to realign a seal, but their efforts did not fix the issue.
Launch controllers then developed a plan to mask data associated with the leak that would trigger a hold by the ground launch sequencer, or launch computer, in a real launch day scenario, to allow them to get as far into the countdown as possible. The time required to develop the plan required extended hold time during the countdown activities, but they were able to resume with the final 10 minutes of the countdown, called terminal count. During the terminal count, the teams performed several critical operations that must be accomplished for launch including switching control from the ground launch sequencer to the automated launch sequencer controlled by the rocket’s flight software, and important step that the team wanted to accomplish.
NASA will hold a media teleconference about the test Tuesday, June 21 at 11 a.m., which will stream on the agency’s website. A live feed of the rocket at launch pad continues to be available.
The launch control team is filling the Space Launch System’s interim cryogenic propulsion stage (ICPS) with liquid hydrogen (LH2) followed by liquid oxygen (LOX) loading. The core stage LH2 and LOX tanks, meanwhile, are being replenished as some of the supercool propellant boils off, meaning the propellant tank will be full through the rest of the countdown.
For the wet dress rehearsal, teams will conduct a test to demonstrate the capability to stop loading the core stage LH2 flow and will then resume with replenishment.
At L-40 minutes, the launch control team will conduct a planned 30-minute hold around 3:58 p.m. EDT prior to the start of the terminal count portion of the test. Mission managers will conduct a final poll on whether to proceed with terminal count at that time.
NASA is streaming live video and live commentary of the test on the agency’s website. Venting on the rocket is visible during these tanking operations.
The launch control team has begun chill down operations and resumed the countdown clock ahead of flowing super cold liquid oxygen (LOX) into the core stage tank. The T-0 time for today’s test is now 4:38 p.m. EDT for the first of the two terminal count runs for the wet dress rehearsal.
The process for filling the core stage tank begins with the chill down, or cooling, of the propellant lines to load the liquid oxygen and liquid hydrogen in preparation for tanking. The team will slowly fill liquid oxygen into the core stage tank with the fast fill beginning soon after. Teams will then proceed to slowly fill the core stage’s liquid hydrogen tank followed by fast fill.
The next blog update will be provided when propellant loading of the interim cryogenic propulsion stage begins.
NASA is streaming live video and live commentary of the test on the agency’s website. Venting may be visible during tanking operations.