KIHEI, Hawaii — Sierra Space conducted one other test of its inflatable habitat technology, demonstrating that the module exceeds its requirements even with the addition of a window in its fabric structure.
The corporate announced Sept. 20 that it performed the fifth in a series of tests of subscale versions of its Large Integrated Flexible Environment (LIFE) inflatable module. The burst test, conducted at NASA’s Marshall Space Flight Center in collaboration with ILC Dover in August, increased the pressure of the module until it finally burst.
A key difference from previous tests was the inclusion of a metallic structure called a blanking plate on the outside of the module. The plate represented a window that might be installed on full-scale versions of the module to see how the structure would affect its strength.
“It was natural in our progression of testing,” said Shawn Buckley, senior director of engineering at Sierra Space, in an interview. Engineering evaluation showed how the inclusion of the structure would maintain adequate margins. “However the only true way in soft goods, and soft goods structures, to essentially confirm that data,” he said, “it to take it through an ultimate burst test.”
Even with the inclusion of the metallic plate, the module burst at 20% higher pressure than the previous test, without the plate. “Not only did we infuse the metallic plate into the article, but we found key areas from the previous tests that we wish to enhance,” he said, leading to the improved results. The module now has a 33% margin over the certification standard for the full-scale LIFE module.
The subsequent step is to perform similar testing on a full-scale prototype. That will probably be just the most recent in a series of “gates” in the general testing, Buckley said, that focuses on various layers of the general LIFE design, including minimizing leaks and testing its resistance to micrometeoroid and orbital debris impacts.
“Over the subsequent 24 months, we’ll move through a series of gates and we’ll start developing our hardware that supports what we just did on this test,” he said. “Flight hardware will come inside the subsequent 24 to 36 months.”
Sierra Space is developing LIFE as one in all the components of the Orbital Reef business space station it’s working on with Blue Origin and other firms. Sierra Space has also proposed flying a LIFE module as a standalone pathfinder that could possibly be used for business research before Orbital Reef.
The test took place within the flame trench on the test stand at Marshall once used for the Saturn 1 and 1B rockets. The world is right for holding debris from the burst test, Buckley said, however it had added other advantages.
“We selected it for pure inspiration,” he said. “For those who drive in front of that after which think concerning the history that has happened in that flame trench, I’ll let you know I used to be inspired.”