HUNTSVILLE, Ala. - Test flights of the X-33 space plane, which NASA once hoped to get off the ground in 1999, have been delayed until 2002 because of fuel tank problems.
A crack was found in the tank after a test, forcing a new round of evaluations for the $1.2 billion project, NASA officials said Thursday.
Gene Austin, who manages the X-33 program at the Marshall Space Flight Center in Huntsville, said the latest delay does not put the program in danger of cancellation, though much of its budget already has been spent.
The pilotless craft is to serve as a prototype for a privately operated plane, possibly replacing the space shuttle, that Lockheed Martin and its partners hope to build.
Last January the plane's manufacturer, VentureStar LLC, announced that plans for a test flight would be delayed because of defects in the graphite-epoxy composite tanks, which hold the liquid oxygen and liquid hydrogen used to power the plane.
Austin said Thursday a final decision hasn't been made on whether aluminum will be used in place of the lighter composite material for the tanks. But he said the problems in the design and manufacture of the tanks have taught NASA enough about the materials that they are likely to be used on more space hardware in the future.
On the Net:
NASA X-33 photo gallery: http://www.dfrc.nasa.gov/gallery/photo/X-33