NASA has completed a complex series of tests on one of the largest composite cryogenic fuel tanks ever manufactured, bringing the aerospace industry much closer to designing, building and flying lightweight composite tanks on rockets. The composites could lower the weight of future rocket tanks by 30 percent and their cost by 25 percent; lighter tanks require less thrust and fuel for liftoff.
The demanding series of tests on the 18-foot diameter tank were conducted inside a test stand at NASA’s Marshall Space Flight Center in Huntsville, Ala. Engineers added structural loads to the tank to replicate the physical stresses launch vehicles experience during flight. The tank successfully maintained fuels at extremely low temperatures and operated at various pressures. Engineers filled the tank with almost 30,000 gallons of liquid hydrogen chilled to -423 F, and repeatedly cycled the pressure between 20 to 53 pounds per square inch, the pressure limit set for the tests.
Dan Rivera, Boeing program manager for the cryotank project, said that this is the first time a tank of this size has been proven to sustain the thermal environment of liquid hydrogen at these pressures. “Our design is also more structurally efficient than predecessors. This is a significant technology achievement for NASA, Boeing and the industry. We are looking at composite fuel tanks for many aerospace applications,” Rivera said.
“This is one of NASA’s major technology accomplishments for 2014,” said Michael Gazarik, NASA’s associate administrator for Space Technology. “This is the type of technology that can improve competitiveness for the entire U.S. launch industry, not to mention other industries that want to replace heavy metal components with lightweight composites.”