The Columbia Accident Investigation Board (CAIB) said in a report released Tuesday that NASA managers were "as much a cause" of the disaster as technical failures.

The CAIB confirmed the long-held suspicion that a piece of foam which broke off an external tank during Columbia's launch pierced the shuttle's protective skin and caused overheating that led to the breakup of the shuttle as it re-entered Earth's atmosphere on February 1.

All seven astronauts on board, including the first Israeli in space, were killed.

The board's report underlined a series of "organisational compromises" and managerial oversights at the National Aeronautics and Space Administration (NASA) that contributed to the tragedy.

The CAIB -- led by retired admiral and government troubleshooter Harold Gehman -- recommended that a new, fully independent technical safety board be established to avoid a repeat of the Columbia disaster.

The inquiry also found that a rescue bid could have been launched to save the Columbia crew and that budgetary constraints and aging equipment contributed to the accident.

President George W. Bush welcomed the report's findings and said "our journey into space will go on."

However, the president, speaking during a stopover in Minnesota, said NASA's next steps would be determined "after a thorough review of the entire report."

The report was delivered Tuesday to the White House, Congress and the families of the seven astronauts who perished on board Columbia.

NASA Administrator Sean O'Keefe said the agency stands ready to comply with the CAIB's safety recommendations, as Columbia relatives criticised the breakdown in NASA's checks and balances.

"We have accepted the findings and will comply with the recommendations to the best of our ability," O'Keefe said in a statement.

The NASA chief, who was appointed by Bush in late 2001, said the agency had already moved to address many of the concerns outlined in the CAIB report, especially the establishment of a new safety directorate.

"As an important step to change the culture of the agency, we have created the NASA Engineering Safety Center at the agency's Langley Research Center in Hampton, Virginia, to provide comprehensive examination of all NASA programs and projects," O'Keefe said.

It remains to be seen whether NASA's new safety group will satisfy the White House and congressional lawmakers.

"Change is good for an organisation. Complacency is something we need to guard against continuously, and we need those checks and balances, as the board report recommends, to carry on," Jon Clark, the husband of Columbia astronaut Laurel Clark, told CNN Tuesday.

Despite its hard-hitting criticisms of NASA -- board member Major General John Barry said the incident had "echoes of Challenger" -- the CAIB team said shuttle flights should resume as soon as is safely possible.

Columbia was the second shuttle to be lost, after the Challenger exploded just after takeoff in 1986. NASA currently has three surviving shuttles: Atlantis, Endeavour and Discovery.

However, the CAIB said NASA will need to fully recertify the shuttles if it wants to fly them in space past 2010.

It also found senior NASA managers had ignored calls from junior technicians for a military satellite to inspect Columbia after the foam shard was spotted hitting Columbia's left wing in launch videos.

The report recommends improving camera surveillance on future missions.

"The board concludes that NASA's current organisation does not provide effective checks and balances, does not have an independent safety program and has not demonstrated the characteristics of a learning organisation," it found.

The CAIB made a series of technical recommendations to Congress in a bid to avoid another disaster -- crucially, NASA has to work to ensure that shuttles do not shed potentially fatal foam shards on future launches.

The report also revealed that a rescue bid could have been launched to save the Columbia astronauts if NASA had realised how critically the shuttle had been damaged during takeoff.

Atlantis could have been readied for a rescue mission if the catastrophic damage to Columbia had been recognised by day seven of its mission.

SPACE.WIRE