Atlantis fueled for launch on Friday

Cape Canaverral (Florida): Technicians at the Kennedy Space Center in Florida started filling space shuttle Atlantis's fuel tank for a launch attempt on Friday after nearly two weeks of delays due to weather problems and technical glitches, officials said.

Liftoff is targeted for 11:41 am (2111 hrs IST) and meteorologists predicted a 70 per cent chance the weather would be suitable for launch.

The shuttle and six astronauts are on a mission to resume construction of the International Space Station, halted after the destruction of shuttle Columbia more than three and a half years ago.

The US space agency is already working on borrowed time, having wrangled extensions for launch attempts after negotiations with its prime space station partner, Russia.

Originally, NASA's window of opportunity to launch Atlantis to the space station closed on September 7. Now the agency has through Saturday, if necessary.

NASA tried to launch Atlantis as early as August 27, but a lightning strike at the launch pad and then the threat of a tropical storm triggered a week of delays.

The flight was rescheduled for Wednesday, but that attempt ended shortly before fueling when a motor inside a critical power unit aboard the shuttle failed to operate as expected.

After two days' debate about the condition of the device, NASA late on Thursday decided to proceed with a final attempt to launch the shuttle this week.

A half-million gallons of cryogenic propellants began flowing into the shuttle's 47-metre tall fuel tank around 3:00 am EDT (0030 hrs IST) after managers cleared Atlantis for a planned 11-day flight.

The primary goal of the mission is to deliver and install the station's second set of power-producing solar arrays.

The mission has already been delayed more than three years while NASA recovered from the 2003 Columbia disaster.

Since the accident, which claimed the lives of seven astronauts, NASA has flown two test missions to check safety improvements made after the disaster.

NASA now requires its crews to conduct extensive in-flight inspections to assure the heat shield is safe for reentry.

The agency plans one more space station assembly mission this year.

The outpost needs to be finished by 2010, when the shuttle fleet is scheduled for retirement.