Nasa 'ignored warning signs'

Debris and other evidence will be examined for clues

Questions are being asked over whether cost-cutting at the US space agency Nasa might have contributed to the loss of the space shuttle Columbia.

As the investigations into what caused the disaster got under way, reports quoted former Nasa technicians as saying the agency ignored safety warnings and eliminated vital pre-launch checks because of budget cuts.

I think... very slowly over the years Nasa's culture of safety became eroded

Don Nelson, former Nasa engineer

Official inquiries have been set up in the wake of the tragedy, including an investigation by Nasa and an independent inquiry comprising federal officials and experts from the Air Force and Navy.

The initial focus of attention is likely to be on damage caused to thermal tiles on the shuttle's left wing, caused perhaps by flying debris which broke off the craft on launch.

Nasa officials said they would work seven days a week, 24-hours a day, to find out what caused the shuttle to disintegrate over Texas, killing all seven astronauts on board.

Safety fears

Investigators will sift through a welter of data, including transmissions from the crew, analysis from satellites and records from the shuttle's sensors, as well as countless pieces of debris scattered over a huge area.

First flight: 1981

Orbiting speed:
17,500 mph

Landing mass: 105 tonnes

Crew (for this mission):7

Columbia: Space pioneer

But concern has been raised that the space agency ignored warning signs that such a disaster was waiting to happen.

A retired Nasa technician, Jose Garcia, said he told former US President Bill Clinton that budget cuts in the 1990s were harming safety checks on shuttles, but no action was taken.

"The managers always say, 'It's safer than it's ever been. Safety first'. All those words come easy," Mr Garci is quoted as saying.

Another former Nasa technician, Don Nelson, told a UK newspaper he had asked President Bush to intervene to "prevent another catastrophic space shuttle accident" because of safety fears, but nothing was done.

"I think what happened is that very slowly over the years Nasa's culture of safety became eroded," he told the Observer newspaper.

In September, 2001, US Senator Bill Nelson told a Senate hearing into shuttle safety that budget plans for the space programme abandoned "some of the most critical safety upgrades for our aging fleet".

Last transmission

None of the three remaining shuttles in the fleet will fly until the inquiry boards are satisfied they know the cause of the disaster.

Nasa officials at the Johnson Space Center in Houston said there had been a loss of key data transmissions from the left side of the orbiter just before contact was lost.

We're going to fix this problem and we going to launch shuttles again

Ron Dittemore, shuttle programme manager

At 0853 EST (1353 GMT) sensors at the trailing edge of the left wing shut down. Their loss was followed by other temperature sensors in a more forward position.

Nasa's chief flight director Milt Heflin told reporters the crew knew there was a problem.

"As far as I know, that was the last transmission from the crew. They were acknowledging, we believe, they'd seen the indication. Then we lost all vehicle data," he said.

Concern has been raised about a piece of insulating foam that was seen to hit Columbia's left wing on launch on 16 January. The foam had come away from the orbiter's external fuel tank.

But Ron Dittemore, the shuttle programme manager, urged people not to jump to conclusions.

"We can't discount that there might be a connection but we can't rush to judgement on it because there are a lot of things in this business that look like the smoking gun but turn out not to be."

"We're going to fix this problem and we going to launch shuttles again," Mr Dittemore said.