Nasa failed to do all that was possible to safeguard the crew
The head of Nasa has pledged to introduce changes to the US space agency following a scathing independent report into the fatal break-up of the Columbia space shuttle.
Nasa administrator Sean O'Keefe is due to give his formal response to the report on Wednesday but has already said some of the recommendations are being implemented.
They include a new centre overseeing the safety of all Nasa's programmes as well as an independent task force to check steps taken to get the remaining shuttles flying again.
Management blunders were as much to blame as technical problems for the destruction of the shuttle, the Columbia Accident Investigations Board (CAIB) said on Tuesday.
Columbia disintegrated as it re-entered the Earth's atmosphere on 1 February, 2003, killing its crew of seven astronauts.
The final conclusions of the CAIB inquiry reaffirmed the view that a breach of the heat shield caused the break-up.
It concluded a piece of foam insulation hitting the shuttle's left wing had blown a hole in the panel. This allowed super hot gases to penetrate, leading to the shuttle's disintegration as it prepared to land.
It said Nasa managers missed at least eight opportunities to evaluate possible damage to the orbiter's heat shield, since similar foam strikes had occurred in the past with no adverse effects.
The problem was overlooked because of a growing culture within the space agency whereby "little by little, Nasa was accepting more and more risk in order to stay on schedule," said the report.
The CAIB concluded that while the current space shuttle was not inherently unsafe, a number of mechanical changes should be made in order to ensure safety in the short term.
"The board strongly believes that if these persistent, systemic flaws are not resolved, the scene is set for another accident," the report said.
Mr O'Keefe said on Tuesday his agency would follow all the report's recommendations necessary to get the shuttles flying again as soon as possible.
"We have accepted the findings and will comply with the recommendations to the best of our ability," he said in a statement.
"The board has provided Nasa with an important road map, as we determine when we will be 'Fit to Fly' again."
At a press conference later, Mr O'Keefe is expected to give details of an Engineering Safety Centre, which will provide a comprehensive safety examination of all the space agency's programmes.
An independent task force is also being set up to oversee every step taken by Nasa to make it safe to fly the remaining shuttles again.
Long-term decisions will need to be made too, says the BBC's science correspondent Christine McGourty.
The shuttles will ultimately have to be phased out, but a lack of investment in the long-term future means there is no successor in sight, says our correspondent.