NASA is ramping up production of hardware and flight elements for the Space Launch System (SLS) rocket, set to make its debut flight in 2018, as various construction and processing facilities around the U.S. turn hard-earned testing into flight products for the EM-1 (Exploration Mission 1) mission that will test most of SLS’s systems as it matures toward the ability to carry humans to targets beyond Low Earth Orbit.
Solid Rocket Boosters:
At Orbital ATK’s facilities in Utah, full-scale production of the flight set, twin five-segment Solid Rocket Boosters (SRBs) began last year and is set to increase multi-fold in 2016.
Orbital ATK has – for several years – been preparing booster casing segments for their role on the EM-1 mission as well as conducting numerous test firings of the five-segment SRBs for qualification and demonstration purposes.
These demonstration and qualification test firings near Promontory, Utah, have led to increased understanding of the nature of the five-segment SRBs, confirmation and validation of their performance range, as well as unseen factors in the casting of the propellant segments for these types of boosters.
All of these tests have led to a more robust booster as well as improvements and enhancements over the four-segment SRB design used throughout the life of the Space Shuttle program from 1981-2011.
This spring, Orbital ATK will conduct its second and final qualification motor test (QM-2), which will see a five-segment SRB fired at the low-end of its operational temperature range.
Overlapping with this test, Orbital ATK will continue its transition from demonstration and qualification to production of flight segment boosters for the SLS program.
This change in operations, which began in earnest last year, will see the commencement of Aft Skirt Refurbishment operations on 25 January.
Moreover, Orbital ATK will complete delivery of an Inert Segment/Pathfinder SRB segment to the Ground Systems and Development Office program (GSDO) on 1 February.
All of these activities will precede the commencement of casting operations for the Aft propellant Segments for EM-1 on 31 March of this year.
Once casting of the Aft propellant Segments begins, the segments will spend the rest of 2016 and all of 2017 at Orbital ATK’s Utah facilities before they are shipped by rail to the Kennedy Space Center, Florida, in late-January/early-February 2018.
However, Orbital ATK is not the only facility around the country to see increased SLS production activity in 2016.
Core Stage at MAF:
At the Michoud Assembly Facility (MAF) in Louisiana, Confidence Article Build (CAB) on the LH2 (Liquid Hydrogen) tank for SLS’s massive Core Stage began on 5 January and is scheduled to run through Tuesday, 19 January.
Following completion of LH2 CAB, MAF teams will reconfigure for CAB on the LOX (Liquid Oxygen) portion of the SLS Core Stage.
CAB for the LOX tank is currently scheduled to begin on 30 January and last for 28 days – with production wrapping on 26 February.
Once these CABs for the LH2 and LOX tanks are complete, MAF teams will transition into the Qualification Article Build (QAB) for the LH2 and LOX tanks.
Current Core Stage production schedules, which are all “under review” at this time, indicate that QAB for the LH2 tank will be completed by 28 March, followed by completion of the LOX tank QAB on 16 April.
Currently, though, teams at MAF are also working through the QAB of the Engine Segment (ES) of SLS’s core stage.
This ongoing operation, being conducted in tandem with the Flight Article Build (FAB) for the ES section of Core Stage-1 (CS-1), is currently scheduled to wrap on 22 February.
FAB for the ES of CS-1 is currently scheduled to wrap production on 26 February, just four days after the ES QAB is completed.
Production of the flight ES for CS-1 marks the first flight element for the EM-1 Core Stage to be produced at MAF.
Moreover, FAB for the engine segment of Core Stage 1 also marks the first time since the final External Tank for the Shuttle Program (ET-138 which flew on STS-135/Atlantis) rolled off the production line in 2010 that MAF will turn out flight element hardware for NASA.
Interim Cryogenic Propulsion Stage:
In addition to the production of flight elements for the Core Stage at MAF, Boeing is also set to complete LH2 tank production for the Interim Cryogenic Propulsion Stage (ICPS) of SLS for the EM-1 mission later this month.
With LH2 tank production for ICPS scheduled for completion on 28 January, assembly of the flight ICPS will start on 26 February at its Boeing/United Launch Alliance production facility in Decatur, Alabama.
Notably, it is now understood that this will be the only ICPS produced for SLS based on a desire to switch to the more powerful Exploration Upper Stage (EUS) on the EM-2 flight of SLS in the 2020s.
Nonetheless, since the EUS can certainly not be ready to support the EM-1 mission of SLS, the ICPS will indeed fly as scheduled on the first flight of the new heavy lift vehicle.
To this end, the second Critical Design Review for ICPS will begin on 17 February with a follow-up Board meeting on 30 March.
Moreover, the Launch Vehicle to Stage Adaptor (LVSA) will complete its Structural Test Article build on 14 April ahead of its scheduled delivery on 6 May.
SLS debut in 2018:
While all of these elements come together at NASA’s various construction and processing facilities around the country, the exact target date for which SLS will attempt its first rise from the launchpad is still a matter of question.
Current processing schedules at the Marshall Space Flight Center note that EM-1 carries a target launch date of 31 July 2018.
However, it has been known unofficially that this launch date is expected to slip easily into September and most likely later into 2018 based on additional processing milestone notations within the NASA community.
Nonetheless, a specific target launch date is noteworthy at this point – more than two years out – as it provides insight into certain processing paths for necessary, critical hardware elements that are still undergoing confidence and test article builds around the country.
One thing that is certain, however, is that the SRBs and the Orion spacecraft itself are not – at this time – considered elements that would impede a summer or late 2018 launch for EM-1.
Images: NASA and L2 – including renders from L2 artist Nathan Koga – The full gallery of Nathan’s (SpaceX Dragon to MCT, SLS, Commercial Crew and more) L2 images can be *found here*)
(To join L2, click here: http://www.nasaspaceflight.com/l2/)