WASHINGTON — Sierra Space has successfully tested a full-scale version of an inflatable module it is developing for commercial space stations.
The company announced Jan. 22 that it performed a burst test of a full-sized version of its Large Integrated Flexible Environment (LIFE) module on a test stand at NASA’s Marshall Space Flight Center, demonstrating that the module exceeds the agency’s safety requirements.
In what is known as an ultimate burst pressure test, the LIFE module was inflated and the pressure inside increased until it burst. The module burst at a pressure of 77 pounds per square inch (psi), nearly 27% above NASA’s recommended level of 60.8 psi, itself four times above the maximum operating pressure for the module.
The test of the full-sized LIFE module comes after Sierra Space performed a series of subscale tests of the technology. In one such test in September, a subscale version equipped with a metallic “blanking plate” intended to simulate a window achieved a 33% safety margin. At the time, the company said the next step was to perform burst tests on the full-scale LIFE module.
The main purpose of the burst tests was to demonstrate the performance of the restraint layer, or pressure shell, of the module. That layer is made of straps of Vectran, a high-strength fiber, along with other fabrics. Sierra Space developed the layer in partnership with ILC Dover.
LIFE is designed to fit within a five-meter payload fairing at launch and then inflate once in orbit. When fully expanded, the module will have a volume of 300 cubic meters, about one third the habitable volume of the International Space Station. Sierra Space has proposed a larger version of LIFE, designed to fit into a seven-meter payload fairing, with a volume of 1,400 cubic meters.
“Sierra Space’s inflatable space station technology offers the absolute largest in-space pressured volume, the best unit economics per on-orbit volume and lowest launch and total operating costs,” argued Tom Vice, chief executive of Sierra Space, in a statement about the test.
LIFE is intended to be one of Sierra Space’s contributions to Orbital Reef, the commercial space station being developed with Blue Origin and others. Sierra Space, though, has proposed launching a LIFE module as a “Pathfinder” space station before Orbital Reef. The company received an unfunded NASA Space Act Agreement in June to give it access to NASA expertise and data to support work on Pathfinder as well as the crewed version of its Dream Chaser spaceplane.
Sierra Space said more tests of LIFE technology are planned for this year, including work on the “atmospheric barrier” and micrometeoroid and orbital debris layers of the module. The company said in September is expected to start work on flight hardware for LIFE in 24 to 36 months.
