Updated

A flawed NASA culture is to blame for the Columbia shuttle disaster, and more tragedies will happen without extensive changes to the space agency, a scathing report found.

The 248-page report by the Columbia Accident Investigation Board (CAIB) (search) was completed late last week after seven months of interviews with scores of engineers and other space workers.

• Raw Data: Columbia Shuttle Report, Part 1 | Part 2 | Part 3 (pdf)

Citing disturbing "echoes" of the Challenger disaster (search)  of 1986, the report states, "NASA's organizational culture had as much to do with this accident as foam did."

"Given the current design of the orbiter, there was no possibility for the crew to survive," the report continues, adding that the space agency lacked "effective checks and balances, does not have an independent safety program and has not demonstrated the characteristics of a learning organization."

Without sweeping changes, the dossier says, "the scene is set for another accident."

President Bush, commenting during a stop in St. Paul, Minn., said the next steps for NASA "must be determined after a thorough review of the entire report, including its recommendations."

"Our journey into space will go on," he said. "The work of the crew of the Columbia and the heroic explorers who traveled before them will continue."

The 13-member board made 29 recommendations for changes, 15 of them related to the shuttle's proposed return to flight.

"The space shuttle is not inherently unsafe," Ret. Adm. Harold Gehman, chair of the CAIB, said at a news conference Tuesday. "If we thought this shuttle was inherently unsafe, we would have said so."

Some critics have disagreed, claiming the current shuttle design needed an upgrade or even a total overhaul.

Gehman said the board was under no pressure from NASA to say that the shuttle was safe to fly.

But the CAIB found many things at the space agency that did need to change, and determined that not much had been done to improve problems since the Challenger accident.

Responding to the report in a news conference Tuesday, NASA Administrator Sean O'Keefe (search) said the agency had already begun implementing some of its findings, which the investigating board had released while it was still working.

"Our first step must be to accept the findings and to comply with the recommendations," O'Keefe said. "This report should serve as a blueprint, as a road map to that objective to fix the problems."

"We intend to comply with the full range of recommendations released today," O'Keefe said, adding that the agency already had established a group to oversee the return to flight, and another "to change the culture" of NASA.

The board concluded that there was too much focus on the shuttle's flight schedule, which led to error.

The report says NASA relied too heavily on computer imagery simulation and mathematics, and not enough on actual photographs, when examining the damage caused by the chunk of insulating foam that flew off during liftoff and struck Columbia's left wing.

There wasn't enough emphasis on the foam strike, which is thought to be what ultimately led to the shuttle's disintegration, the board said. Columbia burned up in the earth's atmosphere upon re-entry on Feb. 1, killing all seven astronauts aboard.

"There are some things that need to be done immediately," said Gehman — things the board categorized as "return-to-flight items."

It divided the remaining proposals into two other categories: those needed to make the shuttle inherently safer in the longer term, and still more recommendations if the orbiter is to fly beyond 2010.

"The changes we recommend will be difficult to accomplish — and will be internally resisted," the report predicted.

Gehman added that the suggested changes, being equally crucial, should not be prioritized.

"We don't have a set of recommendations that are more important than others," he said.

O'Keefe had warned NASA employees workers earlier this summer that the report could be "really ugly,"' and included in the final draft was an analysis of NASA traditions and processes that may have contributed to the disaster.

"There has been a subtle change at NASA," physics professor Robert Park of the University of Maryland told Fox News, referring to the amount of outsourcing the agency has done in recent years.

Park said he'd been told that in the control room at the time of the accident "there were no NASA employees. It was all contractors."

NASA mission managers fell into the habit of accepting flaws in the shuttle system as normal and tended to ignore or not recognize the likelihood of catastrophe, an "echo" of root causes of the Challenger accident, the board said.

"These repeating patterns mean that flawed practices embedded in NASA's organizational system continued for 20 years and made substantial contributions to both accidents," the report reads.

NASA managers missed opportunities to evaluate possible damage to the craft's heat shield from the foam strike. Insulation strikes had occurred on previous missions, but the report said NASA managers had come to view them as an acceptable abnormality that posed no safety risk.

This attitude also contributed to the lack of interest in getting spy satellite photos of Columbia, images that might have identified the extent of damage on the shuttle, and led to incorrect conclusions.

But most of all, the report noted, there was "ineffective leadership" that "failed to fulfill the implicit contract to do whatever is possible to ensure the safety of the crew."

Management techniques in NASA, the report said, discouraged dissenting views on safety issues and ultimately created "blind spots" about the risk to the space shuttle of the foam insulation impact.

Throughout its history, the report found, "NASA has consistently struggled to achieve viable safety programs" but the agency effort "has fallen short of its mark."

For almost a decade, NASA lived on a lean budget that actually lost 13 percent of its purchasing power from 1993 to 2002.

At the same time, it was under pressure to build the International Space Station. To cut costs, the agency reduced its staff and contractor work force from about 32,000 in 1991 to just over 19,000 in 1997.

"The White House, Congress and NASA leadership exerted constant pressure to reduce or at least freeze operating costs [for the space shuttle]," the report said. As a result, "safety and support upgrades were delayed or deferred, and Shuttle infrastructure was allowed to deteriorate."

"Little by little, NASA was accepting more and more risk in order to stay on schedule," the report noted.

At a news conference, some of the board members referred to the Challenger disaster and subsequent calls for increased emphasis on safety at the space agency.

"It didn't get fixed last time," said Steven B. Wallace. "There has to be a different approach."

Another board member, Maj. Gen. John Barry, said, "NASA had conflicting goals of cost, schedule and safety. Unfortunately, safety lost out."

While the report was unflinchingly critical at points, Gehman said a study of the accomplishments of NASA would run far longer than the one issued on the accident. All members of the board endorsed a continuation of the nation's manned space flight program.

The board said it supports launching the next shuttle at "the earliest date" consistent with safety," and said the shuttle is "not inherently unsafe."

During its investigation, the CAIB issued preliminary recommendations that NASA should follow before returning to space.

These included developing a way to repair damaged heat shield panels while the shuttle is in orbit, improving photos taken of the craft during launch, routinely using pictures of orbiting space shuttles snapped by some of the nation's spy satellites and installing a sharper inspections system to detect flawed or failing parts.

Currently there is a space shuttle flight scheduled for March 2004. The question remains whether funding will be available to carry out that mission.

Astronauts and family members of the seven who died aboard Columbia say that in spite of the dangers, they want the shuttle to keep flying.

Jonathan Clark, husband of Columbia astronaut Laurel Clark, said he hoped the shuttle will fly again.

"I think she would want her legacy continued," he told Fox.

He was impressed by the board's investigation.

"I think it's very thorough, extremely thorough. From my perspective, it certainly hits right on the money," said Clark.

"There are a lot of things that are worth risking your life for," Apollo astronaut Walter Cunningham told Fox News.

Fox News' Jamie Colby, Catherine Donaldson-Evans and The Associated Press contributed to this report.