NASA has decided that the Space Launch System (SLS) wet dress rehearsal earlier this week that ended prematurely was sufficient for the agency to move forward with having the giant rocket launch an uncrewed Orion spacecraft to the moon later this summer.
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 team is making its way through countdown operations and wet dress rehearsal activities remain on track. The mission management team will meet this afternoon to review the status of operations.
Overnight, engineers powered up the Orion spacecraft and the Space Launch System’s core stage. Teams also configured several systems on the ground, rocket, and spacecraft and performed activities to prepare umbilicals that connect the rocket and spacecraft to the mobile launcher and are used to provide power, communications, coolant, and propellant.
NASA is streaming live video of the rocket and spacecraft at Launch Pad 39B and will provide live commentary on the agency’s website beginning with tanking operations on June 20.
KENNEDY SPACE CENTER, Fla. (NASA PR) — NASA is on track to begin the approximately two-day wet dress rehearsal for the agency’s Artemis I mission. The test will begin at approximately 5 p.m. EDT June 18 with “call to stations,” when the launch team arrives at their consoles inside the Launch Control Center at NASA’s Kennedy Space Center in Florida. The rehearsal will run the Artemis I launch team through operations to load propellant into the rocket’s tanks, conduct a full launch countdown, demonstrate the ability to recycle the countdown clock, and also drain the tanks to give them an opportunity to practice the timelines and procedures they will use for launch.
KENNEDY SPACE CENTER, Fla. (NASA PR) — At approximately 8:20 a.m. EDT, NASA’s Artemis I Moon rocket arrived at the spaceport’s launch complex 39B after an eight-hour journey ahead of the next wet dress rehearsal attempt.
Teams will work to secure the Space Launch System rocket and Orion spacecraft and mobile launcher to ground support equipment at the launch pad and ensure that the rocket is in a safe configuration in preparation of the upcoming tanking test, planned for approximately two weeks after the rocket arrives back at the pad.
Orion’s European Service Module 4 successfully completed integration activities in Thales Alenia Space’s Turin plant
Thales Alenia Space is responsible for the primary and the secondary structure, and thermo-mechanical systems of ESA’s European Service Modules (ESM)
TURIN, Italy, 31th May 2022 (Thales Alenia Space PR) — Thales Alenia Space, a joint venture between Thales (67%) and Leonardo (33%), has successfully completed the activities related to the final integration of the critical systems of Orion’s European Service Module 4. The module is now on its way to Airbus Defence and Space’s clean rooms in Bremen, Germany. There, it will complete the integration and carry out final tests, supported by Thales Alenia Space engineers on-site.
KENNEDY SPACE CENTER, Fla. (NASA PR) — The Space Launch System (SLS) rocket and Orion spacecraft are slated to return to launch pad 39B at NASA’s Kennedy Space Center in Florida in early June for the next wet dress rehearsal attempt.
HOUSTON (NASA Johnson PR) — Holly Ridings, the first female chief of NASA’s flight directors, will now help lead the agency’s Gateway Program, an international partnership to establish humanity’s first space station around the Moon.
KENNEDY SPACE CENTER, Fla. (NASA PR) — When Artemis I is ready to launch, a range of personnel from NASA, industry, and several international partners will be poised to support the mission. Before they get to launch day, the alignment of the Earth and Moon will determine when the Space Launch System (SLS) rocket with the uncrewed Orion spacecraft atop it can launch, along with several criteria for rocket and spacecraft performance.
KENNEDY SPACE CENTER, Fla. (NASA PR) — NASA will hold a media teleconference at 3 p.m. EDT on Monday, April 18, to discuss the status of the next wet dress rehearsal test of the agency’s Space Launch System (SLS) rocket and Orion spacecraft at Launch Complex 39B at the agency’s Kennedy Space Center in Florida ahead of the uncrewed Artemis I lunar mission.
Due to upgrades required at an off-site supplier of gaseous nitrogen used for the test, NASA will take advantage of the opportunity to roll SLS and Orion back to the Vehicle Assembly Building to replace a faulty upper stage check valve and a small leak on the tail service mast umbilical. During that time, the agency also will review schedules and options to demonstrate propellant loading operations ahead of launch.
The teleconference will stream live on the agency’s website.
Teleconference participants include:
Tom Whitmeyer, deputy associate administrator for common exploration systems development, NASA Headquarters in Washington
Charlie Blackwell-Thompson, Artemis launch director, NASA Exploration Ground Systems program, Kennedy
Mike Sarafin, Artemis mission manager, NASA Headquarters
Through Artemis missions, NASA will land the first woman and the first person of color on the Moon, paving the way for a long-term lunar presence and serving as a steppingstone to send astronauts to Mars.
For updates, follow along on NASA’s Artemis blog at:
KENNEDY SPACE CENTER, Fla. (NASA PR) — Teams concluded today’s wet dress rehearsal test at approximately 5:10 p.m. EDT after observing a liquid hydrogen (LH2) leak on the tail service mast umbilical, which is located at the base of the mobile launcher and connects to the rocket’s core stage. The leak was discovered during liquid hydrogen loading operations and prevented the team from completing the test.
KENNEDY SPACE CENTER, Fla. (NASA PR) — NASA is planning to proceed with a modified wet dress rehearsal, primarily focused on tanking the core stage, and minimal propellant operations on the interim cryogenic propulsion stage (ICPS) with the ground systems at Kennedy. Due to the changes in loading procedures required for the modified test, wet dress rehearsal testing is slated to resume with call to stations on Tuesday, April 12 and tanking on Thursday, April 14. Wet dress rehearsal is an opportunity to refine the countdown procedures and validate critical models and software interfaces. The modified test will enable engineers to achieve the test objectives critical to launch success.
Engineers have identified a helium check valve that is not functioning as expected, requiring these changes to ensure safety of the flight hardware. Helium is used for several different operations, including purging the engine, or clearing the lines, prior to loading propellants during tanking, as well as draining propellant. A check valve is a type of valve that allows liquid or gas to flow in a particular direction and prevents backflow. The helium check valve is about three inches long and prevents the helium from flowing back out of the rocket.
Following the modified test, the Space Launch System rocket and Orion spacecraft will return to the Vehicle Assembly Building (VAB) where engineers will evaluate the valve and replace if needed. Teams are confident in the ability to replace the valve once back in the VAB.
NASA will host a teleconference to discuss details on Monday, April 11. Check back at this blog for an update on the countdown timeline prior to the modified wet dress rehearsal testing for the Artemis I mission. NASA is streaming live video of the rocket and spacecraft on the Kennedy Newsroom YouTube channel.
KENNEDY SPACE CENTER, Fla. (NASA PR) — Teams are preparing for the next attempt to at the Artemis I wet dress rehearsal, pending range availability and restoration of propellants and gases during the test. Through the past two test runs April 3 and 4, engineers accomplished several test objectives that will prepare the teams and integrated systems for launch:
KENNEDY SPACE CENTER, Fla. (NASA PR) — The Artemis I team has ended today’s attempt at the wet dress rehearsal test at 5 p.m. The countdown ended after partially loading liquid oxygen into the Space Launch System core stage tank. This provided the teams a valuable opportunity for training and to make sure modeled loading procedures were accurate. This was the first time using new systems at NASA’s Kennedy Space Center Launch Complex 39B. The team was able to monitor the Artemis I core stage as it was exposed to cryogenic liquids and gather data that will inform updates to propellant loading procedures.
After troubleshooting a temperature limit issue for the liquid oxygen, which delayed the countdown by several hours, the team successfully developed a new procedure for loading the liquid oxygen and filled the tank to 50 percent. Liquid oxygen is an extremely cold, or cryogenic, propellant that is maintained at minus 297 degrees Fahrenheit.
During chilldown of the lines in preparation for loading the liquid hydrogen, the teams encountered an issue with a panel on the mobile launcher that controls the core stage vent valve. The purpose of the vent valve is to relieve pressure from the core stage during tanking. Given the time to resolve the issue as teams were nearing the end of their shifts, the launch director made the call to stop the test for the day. A crew will investigate the issue at the pad, and the team will review range availability and the time needed to turn systems around before making a determination on the path forward.
The wet dress rehearsal is the last major test before launch. This test allows the team to practice propellant loading and thoroughly check out the Artemis I rocket systems as they are exposed to cryogenics.
KENNEDY SPACE CENTER, Fla. (NASA Update) — Teams have decided to scrub tanking operations for the wet dress rehearsal due to loss of ability to pressurize the mobile launcher. The fans are needed to provide positive pressure to the enclosed areas within the mobile launcher and keep out hazardous gases. Technicians are unable to safely proceed with loading the propellants into the rocket’s core stage and interim cryogenic propulsion stage without this capability.
Teams will now meet to determine next steps and establish a go forward plan. The next opportunity to proceed into tanking is Monday, April 4. Teams will discuss range and commodity availability as part of the forward plan.