CAPE CANAVERAL, July 26: Nasa successfully launched space shuttle Discovery on Tuesday after a 2-1/2 year struggle to rebuild the shuttle programme following the fatal Columbia accident. The shuttle, carrying seven crew members, soared into slightly hazy skies, leaving behind a trail of smoke and flames, while the roar of its solid booster rockets rattled windows and shook the ground across Cape Canaveral in Florida.

“On behalf of the many millions of people who believe so deeply in what we do, good luck, Godspeed and have a little fun up there,” Nasa launch director Mike Leinbach told the crew a few minutes before liftoff at 10:39am. “It is time for you to return to flight,” added Mark Taffett, a shuttle test director. “Our hopes and prayers ride with you. Godspeed and I’ll see you in a couple of weeks.”

Discovery’s mission, under veteran astronaut Eileen Collins, is to test new safety measures and heat shield repair techniques introduced since sister ship Columbia disintegrated over Texas on February 1, 2003.

Columbia’s wing had been damaged by falling foam insulation on liftoff, and superheated atmospheric gases tore into the breach when the shuttle came back to land 16 days later. Seven astronauts died.

Nasa has spent more than $1 billion on safety upgrades since then, and worked to correct what investigators called a ‘broken safety culture’ that was too dismissive of risk. Discovery’s other main mission is to deliver several tons of supplies and equipment to the International Space Station, whose construction has been on hold since the remaining three-shuttle fleet was grounded in the aftermath of Columbia.

The shuttle’s launch was delayed for two weeks while engineers searched for the cause of an elusive problem with one of the ship’s hydrogen fuel-level sensors. The sensor glitch cancelled Discovery’s first launch attempt on July 13.

During Tuesday’s countdown, however, all the sensors worked perfectly. Even Florida’s normally fickle summer weather cooperated, and Discovery blasted off smoothly, its two solid rocket boosters pouring out 6.5 million pounds of thrust and enough energy to light 87,000 homes for a day.

Crowds of onlookers, including first lady Laura Bush and President George W. Bush’s brother, Florida Governor Jeb Bush, held their breath during the critical first two minutes of flight, then cheered when launch commentators announced that the shuttle had safely separated from the boosters.

The shuttle arced over the Atlantic Ocean, and settled into its planned preliminary orbit just under nine minutes later after reaching a speed of up to 17,400 mph.

The launch was scrutinized by 112 cameras, and an array of radars, sensors and other imaging equipment so that Nasa can assess how well the newly modified external fuel tank worked. It was foam from the tank that damaged Columbia.

The shuttle crew’s first task will be to use a new 50-foot extension to the spaceship’s robot arm to survey its nose and the leading edges of its wings for damage.

Discovery’s launch was also monitored by Russian cosmonaut Sergei Krikalev and US astronaut John Phillips on the International Space Station.

The shuttle, carrying its commander Collins, pilot Jim Kelly, Japan’s Soichi Noguchi and astronauts Charles Camarda, Steve Robinson, Andy Thomas and Wendy Lawrence, was scheduled to reach the orbital outpost on Thursday for a week-long stay.

The shuttle’s return to flight after a long hiatus also marks the beginning of the end for the aging spacecraft.

President Bush has instructed Nasa to retire the shuttle fleet in 2010, after completion of the space station, and to design a new generation of spacecraft capable of returning humans to the moon and of taking them to Mars and beyond.—Reuters