HUNTSVILLE, Alabama - NASA has successfully pressure-tested a large cryogenic fuel tank made of composite materials. The space agency calls the test results obtained at Marshall Space Flight Center a "game-changing" step toward a new generation of lighter rockets. Watch a NASA video about the process below.
Cryogenic propellants are gases such as liquid hydrogen and liquid oxygen that are chilled to subfreezing temperatures and compressed inside separate tanks. When combined and ignited at liftoff, they provide the thrust to lift a rocket out of Earth's gravity to space. Today's technology requires metal tanks strong enough to withstand the pressures involved, but the weight of the metal counts against the engines' lifting power and limits other cargo. NASA has been trying to develop lighter composite tanks but the composites have had a tendency to leak at the joints. The new tank, built by Boeing in Washington, solved those problems, NASA said.
"The tank manufacturing process represents a number of industry breakthroughs, including automated fiber placement of oven-cured materials, fiber placement of an all-composite tank wall design that is leak-tight and a tooling approach that eliminates heavy-joints," Dan Rivera, Marshall center Boeing cryogenic tank program manager, said in a statement.
In the tests at Marshall's historic west test area, engineers pressurized the tank with liquid hydrogen, cooled it to -423 degrees Fahrenheit and put it through 20 pressure cycles. The tank held.
Now, engineers will build a much bigger composite tank with an 18-foot diameter and test it at Marshall next year.
"Boeing has experience building large composite structures, and Marshall has the facilities and experience to test large tanks," said John Fikes, cryogenic tank deputy project manager at Marshall. "It has been a team effort, with Boeing working with NASA to monitor the tests and gather data to move forward and build even larger, higher performing tanks."
Stephen Gaddis, program manager of the Game Changing Development Program at NASA's Langley Research Center in Hampton, Va., said the breakthrough could "ripple throughout the aerospace industry and change the way we do business."