The need for more time to repair ominous-looking cracks in metal struts that support space shuttle Discovery’s hefty exterior fuel tanks prompted NASA officials Thursday to call for a launch delay, moving the flight from a previously planned early February date to that month’s end. The delay, which follows a failed November launch attempt, has NASA engineers questioning potential manufacturing flaws as the crack-creating culprits. Loaded with supplies for the International Space Station, Discovery is winding down NASA’s three decades in the shuttle business.
