NASA has once again delayed the launch of the space shuttle Discovery as crews work to fix cracks, make modifications, and complete reviews.
The launch will be pushed from February 3 to sometime later that month. NASA is checking to see if International Space Station orbit operations will allow a launch as early as February 24. "NASA managers hope to establish a new target launch date for Discovery's STS-133 mission by the end of next week," the agency tweeted earlier today.
NASA said "progress continues to be made in understanding" what caused the cracks, which were discovered on support beams, or stringers, on Discovery's external tank mid-section, known as the intertank.
Discovery was initially scheduled to take off and head to the ISS on November 1. Leaks, inclement weather, electrical issues, and cracks, however, have delayed that launch more than a half dozen times. Most recently, it was pushed from December 17 to February 3 after more cracks were found on Discovery's external tank
For now, NASA technicians will continue crack repair through the weekend. The shuttle program will also soon start adding radius blocks to the shuttle's stringers, which will provide added structural support to those areas.
"These radius blocks essentially fit over existing stringer edges through which the securing rivets are installed to provide additional structural support," NASA said. "The radius block modification is a known and practiced structural augmentation technique used extensively on the intertank."
Radius block work will start as soon as technicians are doen repairing the most recently discovered cracks. That is likely to happen "in the next day or so, and the modification of the additional 32 stringers is expected to be complete next week," NASA said.
NASA managers will meet with Space Shuttle Program officials on Monday, meanwhile, to review progress and discuss whether even more radius blocks are needed. The launch dates for Discovery and Endeavor - which was pushed to April 1 - will be discussed at next Thursday's Space Shuttle Program Requirements Control Board meeting.