A hard-hitting report today on the loss of the space shuttle Columbia and its seven crew earlier this year will expose a culture of complacency inside Nasa, and cast a shadow over the future of the manned flight programme.
Columbia broke up on February 1, on the way back from what should have been a routine 16-day mission.
The 250-page report of the accident investigation board is likely to be highly critical, not just of Nasa’s response to problems on the last fatal flight but on a lax safety regime that had developed since the 1986 explosion of the shuttle Challenger, again with the loss of seven lives.
Although the 13-member board has yet to publish the report, its broad conclusions have been hinted at often in weekly briefings on the inquiry’s progress.
The report will say that 81 seconds into the launch on January 16, a piece of insulating foam from the shuttle’s external fuel tank broke off and hit the leading edge of the shuttle’s left wing at 725kph. To test the hypothesis that this was the cause of the accident, the investigators fired an 0,8kg piece of the same foam at the wing of the shuttle Atlantis at 853kph. It opened up a 40cm hole.
Foam had broken off and glanced against the shuttle on many occasions. The fatal event was captured on film and there was some discussion among engineers and ground crew, but if it worried mission controllers or Nasa chiefs, there was no sign of it at the time.
On its return Columbia crashed into the earth’s upper atmosphere at eight kilometres a second, using the tenuous air as a means of braking its speed. Sensors recorded a sudden hot spurt within the left wing but by that stage the spaceship’s heat shield tiles were trying to disperse a temperature of 1 100C — inevitable when something enters the atmosphere at that speed.
Then suddenly, over western Texas at an altitude of 64 kilometres and at 18 times the speed of sound, the $1,5bn machine suddenly broke up. Its crew — including the first Israeli to go into space — perished instantly.
For weeks, engineers were picking up wreckage scattered across three states. The only living things to survive the blast were nematode worms sealed in a canister in the shuttle’s biological laboratory.
The inquiry report will focus on a series of questions:
Were there sufficient safety checks before launch?
Once the launch had taken place, did Nasa chiefs take sufficiently seriously the possible threat to the mission?
Could crew members have found and repaired the damage in orbit? If not, could Nasa have launched a spacecraft to serve as a lifeboat, and save the crew?
What must Nasa do to reduce the risks of any such accident in future?
The shuttle fleet is vital to the $100-billion international space station, intended as an orbiting hotel and laboratory for seven scientists but still half-built and now manned by only two crew members, so the inquiry has implications that go far beyond the tragedy of February 1.
As long as the crew remains in space, Nasa needs vehicles that can carry people and supplies to and from the station.
But Columbia — the first of the US shuttle fleet and launched in April 1981 — was a bundle of engineering contradictions from the start.
During the Apollo programme, gigantic rockets such as the Saturn V were used once and abandoned after launch.
The shuttle had to begin each journey with an external fuel tank big enough to accommodate six homes, full of liquid hydrogen and oxygen cooled to -253C, enclosed by enough foam to cover a half-acre field. Its combustion chamber, at full blast, reaches the boiling point of iron, and its three main engines, in terms of watts, match the output of 23 Hoover dams.
On top of that, the shuttle takes off with two solid fuel rocket boosters each almost the height of the Statue of Liberty, together burning the fuel every second of 2-million saloon cars. All this thrust took a vehicle weighing, with fuel, 2 000 tons from a standing start to about eight kilometres a second and orbit around the earth in nine minutes.
Then the shuttle had to endure the cold of space at -100C or more and meet temperatures of 1 100C or more on the way down again, before gliding to the runway at 354 kilometres, twice the speed of a passenger plane. And then, of course, it had to be made ready to do it all over again. – Guardian Unlimited Â