NASA counts down to make-or-break shuttle flight

NASA counted down to the launch of space shuttle Discovery yesterday, hoping to fly a crucial mission whose failure could ground the shuttle fleet permanently and leave the International Space Station unfinished.

Discovery is scheduled to lift off from the Kennedy Space Center in Florida at 3.49 p.m. EDT (1949 GMT) on a voyage to the space station that will test repairs to the shuttle's troublesome fuel tank, which triggered the destruction of shuttle Columbia and the deaths of seven astronauts in 2003.

NASA weather officials predicted a 60 per cent chance the flight will launch as scheduled, an improvement over Friday's estimate. Lightning near the launch site is a potential hazard, but forecasters early yesterday reckoned storms would stay to the south of Cape Canaveral at launch time.

Space centre workers began the process of loading super-cold fuel - liquid hydrogen and liquid oxygen - into Discovery's tank a few minutes behind schedule, but NASA said this would not delay the flight.

"We're looking forward to good weather and when we have it were going to be ready to go," NASA administrator Michael Griffin said at a news briefing on Friday.

Griffin decided to launch the shuttle over the objections of the US space agency's head of safety and its top engineer, who wanted the mission delayed to allow more work on the fuel tank and its insulating foam.