NASA is currently forecasting that Artemis 2 will be ready to launch no earlier than (NET) September 2023, but similar to attempting to forecast when Artemis 1 will be ready to launch, there is also uncertainty in when Artemis 2 might fly. The second joint test flight of NASA’s Orion and Space Launch System (SLS) vehicles will be the first to fly a four-person crew after Artemis 1 goes on an uncrewed lunar orbit mission.
Assembly, integration, and testing of the Artemis 2 Orion and SLS flight hardware continues in the U.S. and Europe independently of Artemis 1 for now, but some Orion hardware from Artemis 1 is still expected to be needed for reuse. The global COVID pandemic is also still having an effect on production activities, which could also affect when Artemis 2 is ready to launch.
Monitoring Orion hardware delivery progress and Artemis 1 schedule
Currently, Artemis 2 is forecast to fly in the second half of 2023 after the long-awaited Artemis 1 uncrewed test flight. The timing for both is uncertain, and the Artemis 2 schedule depends on when Artemis 1 launches because some Orion flight hardware is planned to be used for both missions.
All the flight hardware for Artemis 1 is staged in different locations around the Kennedy Space Center launch site, where Exploration Ground Systems (EGS) is handling launch processing. The final stacking sequence is expected to pick up in early-June with the mating of the SLS Core Stage to its twin Solid Rocket Boosters (SRBs), but the Artemis 1 launch readiness date itself also depends on how smoothly the first-time integrated testing and checkout proceeds; recent estimates place readiness for launch anywhere between November 2021 and March 2022.
Meanwhile, assembly and testing of the Artemis 2 flight hardware continues around the U.S. and in Europe, with some elements already in storage waiting to be called up when needed. But the time between flights is still uncertain.
“It’s tricky when you talk about a specific period of time between Artemis 1 and Artemis 2,” Tom Whitmeyer, Deputy Associate Administrator for Exploration Systems Development (ESD), said in a May 13 interview.
“Where we are is we’re trading back and forth between when the [Orion] Service Module shows up and is ready to integrate with the Crew Module and some of the avionics that we need to put in the Crew Module, but the tricky part is that we constantly re-evaluate our schedule and there’s ways that we can kind of change the order and sequence of when things are installed in the vehicle.”
(Photo Caption: One of the hypergolic propellant tanks for the second Orion European Service Module (ESM) is seen in October 2020 during integration activities in Bremen, Germany. Prime contractor Airbus Defence and Space is finishing integration and functional testing for a planned delivery to KSC later this year.)
The Orion Service Module is composed of the European Service Module (ESM) and the Crew Module Adapter (CMA). ESM Flight Model 2 (FM-2) is currently in final assembly at prime contractor Airbus Defence and Space’s Assembly, Integration, and Testing facility in Bremen, Germany.
Once final assembly and functional testing are complete, ESM FM-2 will be flown to KSC where Orion prime contractor Lockheed Martin is building the CMA and Crew Module. According to NASA’s Fiscal Year 2022 (FY 2022) budget request that was released on May 28, the ESM is scheduled to arrive at KSC in August 2021.
Lockheed Martin’s Orion Assembly, Test, and Launch Operations (ATLO) team will complete preparations to mate the ESM and CMA and test the assembled Service Module. In parallel with the Service Module build-up, Lockheed Martin will continue integration and testing of the Crew Module ahead of mating the two completed Crew and Service Modules.
U.S. government watchdog organizations have cited comments from space agency officials when noting a minimum of 20 months are necessary between Artemis 1 and Artemis 2 to reuse avionics equipment. “According to program officials, NASA will require a minimum of 20 months to refurbish and install these reused components, complete the crew and service module, and complete the EGS prelaunch processing activities,” the Government Accountability Office said in a report published in December 2020.
Most of the work involves tasks that need to be performed after the reused avionics are installed — finishing outfitting of the CMA, ESM, and Crew Module, assembling and testing them as an integrated Crew and Service Module, and then assembling and testing of Orion with SLS. But there’s also a long lead time required for those reused Orion components.
From core stage testing and delivery to booster assembly, it has been a busy couple of months for NASA’s Space Launch System team. Check out the highlights HERE >> https://t.co/Nc6zsthSUG pic.twitter.com/mMp2baPKVE
— NASA_SLS (@NASA_SLS) May 27, 2021
“I always avoid things like 20 months here, 20 months there because it’s really not what we’re looking at,” Whitmeyer said. “The two things that we’re looking at are completing delivery of the hardware for Artemis 2 and completing the Artemis 1 mission and getting the [Orion] hardware off of Artemis 1 and using it for Artemis 2.”
The FY 2022 budget request says the current launch readiness date for Artemis 2 is now no earlier than September 2023. Given the uncertainties, both Artemis 1 and Artemis 2 dates are still being reviewed. “NASA Leadership will evaluate the results of the assessment during Orion’s Systems Integration Review (SIR) in May 2021 leading to Key Decision Point D (KDP-D) review in July 2021 before updating the Artemis I and II (Launch Readiness Dates),” the budget request document said.
Delivery of the Artemis 2 ESM is expected in the middle of northern hemisphere summer, but the lingering effects of the COVID-19 pandemic could still interfere. “For Orion on Artemis 2, maybe even more so than on Artemis 1, some of the challenges we’ve seen have been COVID-related,” Whitmeyer noted.
“With COVID impacts, it’s country by country, and you can have shutdowns and then non-shutdowns, and so we’re constantly monitoring the status of some of this hardware coming together for the Artemis 2 mission. The ESA Service Module is sitting in Bremen, Germany, right now, and they are finishing up most of the work on it. It’s not [fully] complete, but it’s pretty far along.”
“I’m really proud of the Europeans; they’re doing a great job getting the Service Module [completed], and we’re expecting it here this summer,” he added.
The Artemis 2 Crew Module and Crew Module Adapter are being assembled by Lockheed Martin’s ATLO team in the Armstrong O&C Building at KSC. “[The Crew Module] is being outfitted as we speak,” Whitmeyer said.
(Photo Caption: Fluid tubing and wire harnesses for the Artemis 2 Orion Crew Module are obscured by coverings in the Operations and Checkout Building at KSC in February 2021. Orion prime contractor Lockheed Martin is assembling the Crew Module and Crew Module Adapter elements of the spacecraft, where eventually the Crew and Service Modules will be fully assembled and checked out prior to handover to Exploration Ground Systems for launch integration.)
“They’re doing some work to get the ECLSS (Environmental Control and Life Support System) installed; that’s a first-time [activity] because Artemis 2 is our test flight with a crew and so that’s the work that is taking place to continue outfitting the capsule for Artemis 2.”
The CMA recently completed proof testing of its tube welds and is scheduled to be fully outfitted and ready for functional testing in September 2021.
Artemis 2 Orion Crew Module avionics reuse
Artemis 2 will be a crewed test flight to checkout Orion’s ECLSS and other crew systems like display units, hand controllers, and audio communication equipment. In contrast to Artemis 1, where SLS will complete a full trans-lunar injection (TLI) for the uncrewed Orion, on Artemis 2, SLS will leave the Orion and four-person crew in an elliptical high Earth orbit.
The trajectory will set up Orion to fly a “hybrid triple” orbit mission. After the first low Earth orbit, the SLS upper stage, the Interim Cryogenic Propulsion Stage, will fire to place the vehicle in a 42-hour long high Earth orbit.
Orion will separate from SLS and use that single high Earth orbit for an extended ECLSS checkout; at the end of the orbit, Orion will burn its main engine to add the extra velocity needed for TLI. The third and final orbit of the mission will be a lunar flyby followed by a return to Earth for re-entry, descent, and splashdown.
(Photo Caption: The Artemis 2 Orion faces its SLS Interim Cryogenic Propulsion Stage upper stage during a proximity operations demonstration test planned on the first day of the mission. The Artemis 2 flight crew will manually turn their spacecraft around and fly a close range approach to the stage to gather data on the handling qualities of the Orion flight control system for future rendezvous and docking missions.)
More recently, NASA added a proximity operations demonstration test to the Artemis 2 flight. After evaluating options to accelerate development of some hardware and software from the full rendezvous, proximity operations, and docking (RPOD) system, NASA decided not to do that; instead, the flight crew will manually pilot a test using the SLS Interim Cryogenic Propulsion Stage (ICPS) upper stage as the target after separation.
“The astronauts will pilot Orion’s flight path and orientation in manual mode,” NASA’s September 2020 Artemis Plan document stated.
“The crew will use onboard cameras and the view from the spacecraft’s windows to line up with the ICPS as they approach and back away from the stage to assess Orion’s handling characteristics. The demonstration will provide performance data and operational experience that cannot be readily gained on the ground.”
The RPOD system is expected to fly for the first time on Artemis 3 to demonstrate a fully automated rendezvous and docking. “The [Orion] program started the Artemis 3 docking system critical design review (CDR) on March 30, 2021. The review will complete the vehicle design and determine readiness for full-scale fabrication, assembly, integration, and test,” the FY 2022 budget document said.
Originally, at least three years were planned between the first two SLS-launched Orion missions to the Moon, which allowed time for all the primary Orion avionics in the Crew Module to be reused from the first flight to the second. When the second flight was moved from the SLS Exploration Upper Stage back to the ICPS in 2018, the time between flights was reduced; NASA’s Orion Program accelerated the purchase of a second set of core avionics to allow most of the assembly and checkout testing of the Crew Module to continue independently of the Artemis 1 timeline.
#ICYMI – crews at NASA’s Michoud Assembly Facility fully stacked three element together to form the upper portion of the core stage for the #Artemis II mission. DETAILS >> https://t.co/J0TLXZoI8l pic.twitter.com/8W8isweGVM
— NASA_SLS (@NASA_SLS) May 30, 2021
“The core [avionics] are most of the primary [boxes] that allows us to [do] most of the functional integration checkout of Orion, so it’s power distribution units, it’s [flight] computers,” Whitmeyer said. “We did get a second set, they’re available, and that’s what we’re putting on the vehicle right now.”
The non-core avionics can be installed later in the Crew Module integration and testing sequence, and those would still be taken off the Artemis 1 spacecraft after it splashes down. “There’s [the] non-core avionics like a phased-array antenna, Orion IMUs (Inertial Measurement Units)… those are the type of things that we would transition from the first flight to the second flight,” Whitmeyer noted.
A second set of non-core avionics was also purchased but later than the core set, and if Artemis 1 flies soon enough, the first set of non-core avionics boxes would still become available before the second set. “The most likely scenario is we’ll finish up Artemis 1, we’ll take those non-cores off Artemis 1 and put them on Artemis 2, and that’s what we anticipate will happen,” Whitmeyer said.
“We also have on order [the] additional non-cores if for whatever reason we fall really far behind on Artemis 1 by a couple of months. Those would show up, and we would just use the backup set of non-cores.”
Artemis 1 is nominally planned to be a four or six-week long mission, so there would still be a significant amount of time after launch before those Crew Module avionics would be available for refurbishment and reuse. The second set of non-core avionics are projected to be delivered to KSC in early 2022; if Artemis 1 still has not launched by that time, delivery of that backup set of avionics boxes would allow the Artemis 2 Orion schedule to be uncoupled from the Artemis 1 mission.
(Photo Caption: The partially-outfitted Orion Crew Module Adapter for Artemis 2 is moved out of clean room in the Operations and Checkout Building at KSC in June 2020. Tube welding is done in the clean room on the individual Crew Module and Crew Module Adapter (CMA) elements during assembly and also on the integrated Service Module after the CMA and European Service Module are integrated.)
NASA’s FY 2022 budget request document says that the non-core avionics from the Artemis 1 spacecraft are expected to be delivered to KSC after refurbishment in spring 2022.
Whitmeyer also noted that Orion and Lockheed Martin are looking at ways to reorganize blocks of work around when either set of the non-core Crew Module avionics becomes available for Artemis 2. “We constantly re-evaluate our schedule, and there’s ways that we can kind of change the order and sequence of when things are installed in the vehicle,” he said.
“I’m always reluctant to get into ‘X’ number of months because by the time I’m done telling you that I will have figured out some other thing. We’re working with the Orion folks to look at our workforce loading at the Cape, and depending on what we see in terms of the actual Artemis 1 launch date, we have different types of ways to expedite recovery operations and bring the avionics back to the O&C.”
“When I look at getting the avionics off Artemis 1 and getting them onto Artemis 2, I’ve got a couple of different options of when I re-integrate them into the flow,” Whitmeyer added.
Other Artemis 2 hardware assembly and integration also continues
In addition to the Orion flight hardware build up for Artemis 2, the SLS program is assembling the elements of its second vehicle, and EGS is planning on upgrades to the KSC ground support infrastructure for the first crew launch. Within the SLS hardware elements, the Core Stage is the most complicated, but is not currently pacing the overall schedule.
“Core Stage-2 is working its way through MAF (Michoud Assembly Facility), and we’re actually making pretty good progress with engine section complete later this year,” Whitmeyer said. “That’s currently not on the critical path, though I am always careful to make sure we always take these things a step at a time.”
On May 24, Boeing lifted the Core Stage-2 forward skirt into place on top of the liquid oxygen (LOX) tank in a stacking cell at MAF in New Orleans. The second structural mate was the last one for the forward join, which won’t be complete until after internal power, data, and propulsion system connections are made.
(Photo Caption: The forward skirt for Core Stage-2 is lifted into place on top of the liquid oxygen tank as a part of final assembly of the stage elements. Structural assembly and outfitting both inside and outside the stage will continue over the next year with completion currently forecast for some time on FY 2022.)
Meanwhile, Northrop Grumman has completed the 10 solid rocket motor segments for Artemis 2 at their Promontory production facility in Utah, and they are in storage there until they are needed for launch integration. Northrop Grumman is also processing the second set of forward and aft assemblies for the boosters at KSC; those assemblies will be mated with the motor segments after they are shipped by rail to the launch site.
Assembly and outfitting of the stage and spacecraft adapters is also in work by the SLS Program at the Marshall Space Flight Center in Huntsville, Alabama. The Launch Vehicle Stage Adapter (LVSA), which connects the SLS Core Stage and Interim Cryogenic Propulsion Stage, and the Orion Stage Adapter (OSA), which connects the ICPS upper stage to Orion, are being manufactured for availability next year. United Launch Alliance was also expected to complete the ICPS for Artemis 2 in 2022.
In between Artemis 1 and Artemis 2, EGS is planning on modifications and upgrades to Mobile Launcher-1 (ML-1), the VAB, and in the Launch Pad 39B area. With crewed flights scheduled to begin on Artemis 2, an Emergency Egress System needs to be integrated with ML-1’s launch umbilical tower and with support structures at Pad 39B.
The system would allow personnel up on the Mobile Launcher’s umbilical tower at the pad, while the vehicle is fueled during the final countdown, to make an emergency evacuation away from the tower to bunkers and protection in the pad perimeter area. In addition to modifications to support emergency egress from the ML tower, other changes are planned for ML-1 prior to its supporting Artemis 2.
The KSC work solicitation in the request for proposals (RFP) notes that the scope of the work includes: “Structural modifications to ML-1 to add platforms for the emergency egress system, adding ground cooling systems, relocating a rest room, adding fire detection systems, modifying the fire suppression systems, camera systems, and other facility systems, and building and installing new cables that are potted and molded for several critical systems including the launch release system, hazardous gas detection system in order to safely launch astronauts for Artemis 2.”
Some of the work tasks are planned on ML-1 prior to the Artemis 1 launch, but approximately 150 days of work are planned on tasks that would be performed in between Artemis 1 and Artemis 2.
Another EGS project planned in between the two launches are modifications to Environmental Control Systems (ECS) in the VAB. “To support launches post Artemis I, modifications are planned to the ECS that will enable it to support a Block 1 and Block 1B vehicle,” the FY 2022 budget request document says.
“This will require modifications to the existing circuits; however, these circuits must be maintained throughout the entire Artemis I launch campaign.” EGS is looking at ways to ensure those modifications can be completed without interfering with the schedule to Artemis 2 launch readiness.
Lead image credit: Mack Crawford for NSF.