Cellular Launcher 1 (ML1, or ML) is on its means again to the Car Meeting Constructing (VAB) on the Kennedy Area Heart after efficiently launching the SLS rocket and Orion/European Service Module duo on the Artemis I mission from Launch Advanced 39B (LC-39B) on Nov. 16, 2022.
The ML now must be repaired from injury sustained throughout SLS’s debut launch in addition to bear a sequence of modifications to arrange it for its position on future SLS launches the place crew will board the Orion for departure to the Moon and Lunar Gateway.
Publish-Artemis I launch ML injury evaluation
General, regardless of the period of time it took to securely acquire entry to the ML as a consequence of elevator injury, the overwhelming majority of the injury sustained from SLS’s first launch was as anticipated, in line with David Sumner, Mission Supervisor for ML1 on Artemis II, in an interview with NASASpaceflight.
“We had some expectations of some smaller gear that we sort of anticipated we’d see some injury, however we did see another areas that some issues occurred that we weren’t totally anticipating,” Sumner defined.
“The elevators took some injury. We’ve got two elevators on the Cellular Launcher that go all the way in which up the tower. These took some injury, after which we had some pneumatic and electrical panels, some which are up the tower, that took some injury as properly that we weren’t anticipating.”
General, Sumner defined that the ML construction itself was in good situation, and no modifications had been wanted to facilitate the ML’s rollback to the VAB.
“Instantly following launch, we had crews exit and begin safing, doing the air checks and safing the ML,” added Sumner. “That took a few days, securing the ML, to permit different individuals doing structural assessments on the ground grating, ensuring that the ground was secure to stroll on.”
Towards mitigating the surprising injury seen in post-flight evaluation, Sumner mentioned that steel banding straps would seemingly be positioned across the panels and cupboards to make sure their doorways stay shut, not like their post-Artemis I situation.
Moreover, the elevators would require substantial refurbishment, and the blast doorways which had been in place for Artemis I to guard the elevator shafts and automobiles will even require upgrades based mostly on their failures as a result of energy of the SLS rocket.
Conversely, the swing arms on the ML largely held up per preflight predictions, with some anticipated, minimal injury towards the ends of the arms famous.
Particularly, quite a few smooth items supplies on the swing arms, comparable to hoses and catch again nets, had been misplaced in the course of the launch.
Nevertheless, it was a component of the ML that didn’t obtain a lot consideration in the course of the Artemis I launch marketing campaign — however that will likely be very important to Artemis II and past — that was the topic of vital post-liftoff checkouts.
This morning at 6:40 am EST, the cell launcher atop the crawler transporter 2, had first movement in its roll again to the Car Meeting Constructing following the launch of Artemis I on Nov. 16 at 1:47 am EST. pic.twitter.com/FETL4Embal
— NASA’s Exploration Floor Programs (@NASAGroundSys) December 8, 2022
The Crew Entry Arm (CAA) was exercised by means of its vary of movement to make sure groups may maneuver it from its totally retracted place, which it must be in for heart of mass concerns on the ML throughout rollback, to its totally prolonged place, which it must be in earlier than getting into the VAB.
“The opposite large constraint for us to roll again to the VAB was the Crew Entry Arm,” mentioned Sumner. “It was in a retracted place; to ensure that us to get into the VAB, we have to prolong the CAA, and so on the pad, we had been in a position to exhibit that we may swing the CAA. That was an enormous deal.”
The one different merchandise of notice when it comes to getting ready the ML for rollback was eradicating and or securing any items of apparatus that had been unfastened.
By way of classes realized from the general Artemis I pad movement and any modifications which may stem from that component of the method, Sumner famous that all the things went pretty properly in that regard.
Sumner did notice, nonetheless, that there could possibly be pending modifications to enhance the liquid hydrogen techniques on the ML as a consequence of points confronted in the course of the numerous Moist Costume Rehearsal and counts; nonetheless, any modifications in that regard have but to be finalized.
Refurbishment, modifications, and timelines for Artemis II
Not like rollout and rollback operations with SLS, which had been carried out with out breaks, the rollback of the empty ML will happen throughout two days.
This break permits groups time to relaxation and never work in a single day when not required.
The ML will likely be introduced again to simply exterior the VAB on Thursday, Dec. 8, the place it’s going to then spend the evening outside earlier than groups resume roll operations on Friday, Dec. 9 to maneuver the ML utterly inside Excessive Bay 3 of the VAB.
As soon as there, the ML will spend between 4 to 6 weeks present process continued post-launch assessments earlier than the Crawler Transporter groups will choose up the ML and transfer it out of the VAB to the West Park Website — which is situated to the north of the VAB and is the western-most of the 2 ML park websites.
“We’re fairly particular on January 2023,” mentioned Sumner. “Someday in January, we ought to be on the West Park Website.”
There, the ML will bear a majority of its refurbishment and modification work, together with set up of the vital Emergency Egress System {hardware} which will likely be wanted for crew flight operations with Artemis II.
“What’s thrilling for Artemis II is that’s going to be our first manned mission again to the Moon,” mentioned Sumner. “And so nearly all of our focus is de facto within the higher stage of the tower of the Cellular Launcher, principally the 260-foot [79-meter] stage and above.”
The higher ranges of the ML would be the focus of the lion’s share of modification work to arrange the SLS ML for crew flights on Artemis II. (Credit score: Stephen Marr/NSF)
“And we’re actually centered on that crew stage, ensuring it’s prepared. Ensuring the Crew Entry Arm is prepared for the crew, ensuring that’s licensed. Getting the Emergency Egress System put in, ensuring it’s examined coming off the crew stage.”
Whereas on the West Park Website, the entry platforms for the 4 egress baskets — which might be used to move personnel safely away from the tower within the occasion of an emergency — will likely be put in.
“After we’re on the West Park Website, we’re planning to put in three completely different platforms on the facet of the ML tower, and a type of platforms goes to have a set of 4 hoists on high of it.”
The hoists are roughly 99 meters (325 toes) above floor stage and can every have a cable that may stretch all the way down to the bottom.
This cable is vital to how the general Emergency Egress System will likely be linked between floor structure and the ML following rollout of a completely stacked SLS rocket destined to hold crew.
“After we get to the pad, we’ll stretch a cable down all the way in which to the bottom floor after which out to the perimeter fringe of Launch Advanced 39B the place our touchdown — we name it the terminus — space is. And we’ll stress these cables and join them as much as the tower.”
That can present the zip-line-like wires — like these used all through the Shuttle Program and nonetheless used at neighboring 39A for Falcon 9 crew launches — that the egress baskets would experience to the bottom from the Crew Entry Arm stage of the ML.
These hoists will likely be put in on the West Park Website, however their major take a look at and integration, in addition to verification and validation, must happen at pad 39B.
It will necessitate one other journey out to the launch pad for the ML previous to Artemis II stacking.
General, the ML is anticipated to spend a couple of months on the West Park Website, although specific timelines will not be at present identified as a result of uncertainty that is still in post-Artemis I launch injury refurbishment timelines.
Additionally on the West Park Website, pneumatics adjustments will likely be carried out on the crew entry stage. Groups will even set up respiration air and gaseous nitrogen stations and techniques that will be wanted within the occasion of emergencies.
Further work on the West Park Website will even embody modifications to the ignition overpressure safety/sound suppression system that had been deliberate earlier than the Artemis I launch.
Water flows from the rain chook heads onto the ML deck because the engine ignition sequence progresses for Artemis I. The rain birds will likely be modified for various water movement patterns for Artemis II. (Credit score: Nathan Barker/NSF)
“The ignition overpressure sound system down on the base of the ML the place all of the water comes out at time of launch — we’re making some modifications to the rain chook heads,” famous Sumner.
The modifications to the rain birds are based mostly on the projected launch profiles for Artemis II and a want to direct water barely in a different way to keep away from water impingement onto the rocket.
The change necessitates taking the heads off of the rain birds and putting in new ones that can give the water a distinct movement throughout the ML because it deadens the acoustic atmosphere at RS-25 engine and Stable Rocket Booster ignition.
As soon as these modifications and refurbishments are full on the West Park Website, the Crawler Transporter will as soon as once more choose up the ML and haul it out to LC-39B for its Emergency Egress System testing.
After arriving on the pad and connecting the zip-line-like cables from the hoists to the touchdown space, the hoists will then be used to individually raise the 4 egress baskets to their correct positions, the place the hampers will then be secured and locked in place forward of testing.
At current, testing and validation of the Emergency Egress System will contain using weights and a number of runs of the hampers in addition to drills to make sure personnel are accustomed to the right way to make the most of the system ought to they should.
Previous to the graduation of the Shuttle program, the slide wire emergency egress baskets had been by no means examined with people, one thing that prompted concern throughout STS-41D/Discovery’s on-pad abort in June 1984, which led to an engine shutdown on the pad at T-6.4 seconds.
Throughout that abort, launch personnel didn’t wish to inform the crew to make use of the slide wire baskets as they’d not been totally examined.
Following the Challenger catastrophe in 1986 and a must re-certify the whole Shuttle program earlier than STS-26/Discovery’s Return To Flight mission, emergency egress basket coaching with astronauts onboard was finally carried out; nonetheless, subsequent checks of the system utilized ballasts as a substitute of people.
In response to Sumner, the present plan is to likewise use ballasts for testing and validation of the whole Emergency Egress System for SLS — although the eventual use of people in a take a look at has not been utterly dominated out presently.
This particular component of the ML’s return to pad 39B carries some uncertainty towards the general schedule, as certifying the processes for putting in the Emergency Egress System and validating its general use may take “a little bit little bit of time.”
Likewise, the Crew Entry Arm will even be a spotlight of the ML’s return journey to 39B earlier than stacking for Artemis II.
SLS throughout rollout, shortly after stopping to retract the Crew Entry Arm for the rest of roll operations to LC-39B in early Nov. 2022. (Credit score: Stephen Marr/NSF)
Whereas the choice was made to put in the arm and put it by means of a few of its maneuvers in the course of the Artemis I movement, it was notably not used on the identical instances when it will throughout a launch countdown with crew.
To that finish, the CAA really must be licensed for human flight, and this can contain shifting it throughout numerous wind occasions and at numerous wind angles in addition to at completely different arm motion speeds.
All of this can validate and confirm that the arm is secure for people to be on throughout sure climate occasions in addition to the arm’s potential to maneuver below numerous wind profiles within the method it might want to on launch day.
Beneath nominal operations, the arm will transfer very slowly away from the Orion capsule at T-6 minutes. However, ought to an emergency come up after that time that doesn’t require activation of the Launch Abort System however would possibly require the crew to shortly egress Orion and the ML, the arm must transfer again into place far faster than when it retracted.
This is likely one of the motion checks that will likely be studied when the ML makes its return journey to the pad in 2023.
These particular checks for the CAA don’t require an entire 100% seize of information in any respect the varied wind ranges and wind speeds the CAA may need to function in.
Not like its retracted rollout place (pictured), the CAA have to be totally prolonged to its “mate” place the place Orion can be earlier than getting into the VAB as there is no such thing as a solution to swing the arm as soon as contained in the constructing. (Credit score: Julia Bergeron/NSF)
For this specific a part of CAA verification and validation, solely 80% of the completely different variables are wanted from a knowledge standpoint, after which sufficient knowledge may have been collected that fashions may simulate the remaining 20% and confirm the whole envelope of wind load and directional operations the arm would possibly encounter.
As soon as all testing and verification and validation operations are full at LC-39B, the Crawler Transporter will as soon as once more choose up the ML and return it to Excessive Bay 3 contained in the VAB the place closing multi-element verification and validation work will happen.
As soon as these steps are full, the Cellular Launcher will likely be prepared for stacking operations for the Artemis II mission which is able to return people to the neighborhood of the Moon.
Whereas the crew of Artemis II has not but been introduced, it’s already identified {that a} Canadian Area Company astronaut may have one of many seats on board the mission — changing into the primary non-American to journey to the Moon.
At current, Artemis II is deliberate to launch no sooner than mid-2024 on a free return trajectory which is able to contain a closest method flyby to the Moon of seven,400 km.
(Lead picture: The ML on its return journey to the VAB on Dec. 8 after efficiently launching Artemis I on Nov. 16, 2022. Credit score: NSF/Area Coast Stay)
