The head of Nasa has said the report into the fatal break-up of the Columbia space shuttle was a "seminal moment" for the space agency and its recommendations would be fully implemented.
Nasa says both organisational and technical changes will be made
Giving his formal response to the report by the independent Columbia Accident Investigations Board (CAIB), published on Tuesday, Nasa administrator Sean O'Keefe said some of the recommendations were already being carried out and he vowed to make further changes.
"This report gives us a blueprint, a roadmap to fix the problems and return to space," Mr O'Keefe said.
Columbia disintegrated as it re-entered the Earth's atmosphere on 1 February 2003, killing its crew of seven astronauts.
The report was highly critical of the agency, saying that management blunders were as much to blame as technical problems for the destruction of the shuttle.
The final conclusions of the CAIB inquiry reaffirmed the view that a breach of the heat shield caused the break-up.
It said that 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.
The report said Nasa managers had missed at least eight opportunities to evaluate possible damage to the orbiter's heat shield, because 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 report makes 29 major recommendations aimed at both a short term return to space and continuing exploration in the long term.
"They have been clear throughout the report, repeatedly, that there must be institutional changes," Mr O'Keefe said. "That is what we are committed to doing."
Mr O'Keefe said the safety of the crew was and always had been the paramount objective of the agency.
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 warned.
The investigation panel is concerned about long-term safety, once the impact of the disaster starts to recede.
The board found that in the wake of the 1986 explosion of the Challenger space shuttle, Nasa had vowed to change - but had quickly slid back into old practices.
Among the recommendations that Nasa says are already being acted upon is the setting up of an Engineering Safety Centre to oversee all Nasa's programmes, and an independent task force to check steps taken to get the remaining shuttles flying again.
Tough decisions on the next generation of space vehicles must be made
The BBC's science correspondent Christine McGourty says that Nasa is still reeling from the impact of the damning report.
Already key managers involved in the mission have been moved, including Jerry Smelser, the project manager who oversaw the shuttle's faulty external tank, and more heads may yet roll.
Mr O'Keefe himself has been in his post for just one year and a half. He is a professional manager, not a space scientist or engineer, and many outsiders see him as the right person to see through the radical reforms in management and culture that are required in the agency.
Decisions on what will succeed the shuttle will need to be made too, our correspondent says.
The shuttles will ultimately have to be phased out, but a lack of long-term investment means there is no successor in sight.