September 8, 2015 – On Saturday, September 5, Lockheed Martin and NASA engineers at Michoud Assembly Facility in New Orleans welded together the first two segments of the Orion crew module that will fly atop NASA’s Space Launch System (SLS) rocket on a mission beyond the far side of the moon.
“Every day, teams around the country are moving at full speed to get ready for Exploration Mission-1 (EM-1), when we’ll flight test Orion and SLS together in the proving ground of space, far away from the safety of Earth,” said Bill Hill, deputy associate administrator for Exploration Systems Development at NASA Headquarters in Washington. “We’re progressing toward eventually sending astronauts deep into space.”
The primary structure of Orion’s crew module is made of seven large aluminum pieces that must be welded together in detailed fashion. The first weld connects the tunnel to the forward bulkhead, which is at the top of the spacecraft and houses many of Orion’s critical systems. The forward bulkhead must handle extreme loads because that is where the parachutes are connected when they deploy during reentry. Orion’s tunnel, with a docking hatch, is the passageway astronauts crawl in and out of when Orion is docked with another vehicle.
“Each of Orion’s systems and subsystems is assembled or integrated onto the primary structure, so starting to weld the underlying elements together is a critical first manufacturing step,” said Mark Geyer, Orion Program manager. “The team has done tremendous work to get to this point and to ensure we have a sound building block for the rest of Orion’s systems.”
Engineers have undertaken a meticulous process to prepare for welding. They have cleaned the segments, coated them with a protective chemical and primed them. They then outfitted each element with strain gauges and wiring to monitor the metal during the fabrication process. Prior to beginning work on the pieces destined for space, technicians practiced their process, refined their techniques and ensured proper tooling configurations by welding together a pathfinder, a full-scale version of the current spacecraft design.
Through collaborations across design and manufacturing, teams have been able to reduce the number of welds for the crew module by more than half since the first test version of Orion’s primary structure was constructed and flown on the Exploration Flight Test-1 last December. The Exploration Mission-1 structure will include just seven main welds, plus several smaller welds for start and stop holes left by welding tools. Fewer welds will result in a lighter spacecraft.
“After going through the manufacturing process for the Exploration Flight Test-1 vehicle, we determined we could reduce the vehicle’s weight if we lessened the number of pieces being welded together since those welded areas weigh more,” said Mike Hawes, Lockheed Martin Orion vice president and program manager. “So for this next spacecraft, seven bigger pieces are coming together, instead of the eighteen for EFT-1, which makes the welding process a little more challenging than before.”
In order to certify the new welding process, the team at Michoud Assembly Facility welded a pathfinder vehicle to verify the design changes and welding changes would perform as expected.
“We used the pathfinder to make sure we weren’t being too ambitious with our design changes,” said Hawes. “It allowed us to verify the process would work before we used it on actual flight hardware.”
During the coming months as other pieces of Orion’s primary structure arrive at Michoud from machine houses across the country, engineers will inspect and evaluate them to ensure they meet precise design requirements before welding. Once complete, the structure will be shipped to NASA’s Kennedy Space Center in Florida where it will be assembled with the other elements of the spacecraft, integrated with SLS and processed before launch.
EM-1 will be the first test of the fully integrated Orion and SLS system. The mission, expected to launch in 2018, will send Orion into lunar distant retrograde orbit — a wide orbit around the moon that is farther from Earth than any human-rated spacecraft has ever traveled. The mission will last more than 20 days and will certify the design and safety of Orion and SLS for human-rated exploration missions.
Lockheed Martin Space Systems, based in Littleton, Colorado, leads the Orion industry team as the prime contractor building the Orion spacecraft.