[image-51][image-67][image-83]For more than 50 years, metal tanks have carried fuel to launch rockets and propel them into space, but one of the largest composite tanks ever manufactured may change all that. This spring, that tank--known as the composite cryotank--is set to undergo a series of tests at extreme pressures and temperatures similar to those experienced during spaceflight.
"NASA focused on this technology because composite cryogenic tanks promise a 30 percent weight reduction and a 25 percent cost savings over the best metal tanks used today," said Michael Gazarik, associate administrator for NASA's Space Technology Mission Directorate. "It costs thousands of dollars to deliver a pound of cargo to space, so lighter tanks could be a game changer allowing rockets to carry more cargo, more affordably."
The 18-foot-diameter (5.5 meter) composite tank just completed final assembly at the Boeing Developmental Center in Tukwila, Wash. Soon it will be loaded onto NASA's Super Guppy, a large, wide-bodied cargo aircraft, that will carry it on a two-day journey to NASA's Marshall Space Flight Center in Huntsville, Ala., where it will be filled with extremely cold, or cryogenic, hydrogen propellant and undergo a series of tests throughout the summer.
"Successful tests last year with an 8-foot-diameter tank gave us the confidence that we could build and test a much larger composite tank," said Steve Gaddis, manager for Space Technology’s Game Changing Development Program. "This tank is the size of metal tanks that fuel full-size rockets today, so this is a true milestone in composite tank design and fabrication."
A team of engineers from Boeing and NASA designed and manufactured the tank. NASA experts learned from prior tank designs and testing and helped devise ways to combat imperfections such as microscopic leaks, found in previous composite tanks. The team leveraged Boeing's experience producing composites for aircraft to use a unique fiber-placement technique and new materials that did not require expensive curing processes in autoclaves, procedures traditionally associated with composite production.
"Advances in composite materials and manufacturing offer some of the greatest potential for improvements in cost, schedule and overall performance for a wide range of NASA missions," said John Vickers, the program manager for the Composite Cryotank and Technologies Demonstration project at the Marshall Center. "We have improved composite manufacturing without adding risks or costs to any of NASA's current projects. We want to advance this technology, so tanks are ready as NASA's Space Launch System, the largest most powerful rocket ever built, evolves.”
When the tank arrives at the Marshall Center, it will move to a clean room and be prepared for testing at a recently refurbished test stand. Here, the tank will come to life as it is filled with liquid hydrogen, cooled and pressurized. As it undergoes this endurance testing, NASA and Boeing engineers will monitor data to see how it performs compared to metal tanks and the smaller 8-foot-diameter (2.4-meter) tank tested at Marshall last summer. Engineers will monitor testing from a new centralized control room, which is shared by several test facilities and has updated video, data acquisition and communications systems.
[image-36]"Boeing and NASA assembled some of the world’s experts to design, build and test the tank,” said Dan Rivera, the cryotank program manager within Boeing Research & Technology, the company's advanced research and development organization. "We used new composite materials and an innovative design capable of withstanding harsh launch vehicle environments. Both the approach and the technology for the design and manufacturing are revolutionary.”
For more information on the Composite Cryotank Technologies and Demonstration project, visit: http://gcd.larc.nasa.gov/projects/composite-cryogenic-propellant-tank/#.Uv-1QY1xQfU
For more on NASA’s Space Technology Mission Directorate: http://www.nasa.gov/directorates/spacetech/home/index.html#.Ux4cyCTQCck
Marshall manages the SLS Program for NASA. For more information on SLS, visit: http://www.nasa.gov/sls