Deep inside a windowless building at Johnson Space Center in Houston is a room where NASA managers, engineers and safety experts will make life-and-death decisions about the fate of the space shuttle Discovery when it rockets into orbit next month.

The centerpiece of the 6-month-old mission-management team's room is a horseshoe-shaped table that enables each of the group's 24 members to talk face to face when they gather each day at 1 p.m. during the two-week-long space flight. There are no assigned seats at the table, not even for the team's chairman.

It is designed to discourage the top-down hierarchical atmosphere that reigned two years ago when another mission-management team made the fatal decision to bring the space shuttle Columbia home after a stray piece of foam insulation from the orbiter's external fuel tank punched a hole in the vehicle's wing shortly after liftoff.

"We don't have one person doing all the talking now," said Charles Young, the group's training coordinator. "We are really working to learn to work as a team."

The new room is at the heart of the cultural and organizational changes at the National Aeronautics and Space Administration (NASA) that were demanded by the federal board that investigated the Columbia accident.

Fixing the tank

Such changes have been overshadowed by modifications to the external fuel tank to reduce the chance of repeating the foam loss that led to Columbia's destruction and the death of seven astronauts. Workers at an assembly plant in New Orleans spent the past two years removing the so-called bipod ramp, an aerodynamic fin that was the source of the foam that damaged Columbia.

But the federal board that investigated the Columbia accident concluded in a scathing August 2003 report that institutional weaknesses were as much to blame for the tragedy.

"NASA's blind spot is it believes it has a strong safety culture," the investigators wrote. "The board strongly believes that if these persistent, systemic flaws are not resolved, the scene is set for another accident."

The report described NASA as a place where concerns about meeting schedules and operating within tight budget constraints could trump worries about safety risks.

A work in progress

Investigators stopped short of demanding a change in the culture before returning a shuttle to space, saying the agency should have a plan to make deep organizational changes when Discovery leaves for its mission.

The agency's former administrator, Louisiana State University Chancellor Sean O'Keefe, said the cultural transformation remains a work in progress. "It's not there yet. You have to work at this all the time. It's a task that still has to be done," he said last week.

A survey of NASA workers taken last fall by Behavioral Science Technology, the California company hired to help the agency change its culture, found that safety conditions had improved. Yet, the survey revealed that a number of nonmanagement workers feel things haven't changed.

"Fear of reprisal still strong if you challenge central management," wrote one survey respondent.

The stakes that the agency faces couldn't be higher. NASA is under tremendous pressure to return the remaining three shuttle orbiters to a regular flight schedule so that work can resume on the half-completed international space station.

The agency also is working under a mandate from President Bush to retire the shuttles by 2010 and to develop a new space capsule and rocket system that would return astronauts to the moon. This would lay the groundwork for building a permanent lunar station and sending a human to Mars. NASA has to finance the new space-exploration plan with money now being spent on the shuttle program.

For years before the Columbia accident, NASA managers had known that pieces of foam often broke from external tanks during liftoff and that the pieces sometimes collided with the orbiter and caused damage to its ceramic heat-protective tiles. Even so, NASA did little to study or fix the problem. Instead, managers concluded that as long as the problem had never put the shuttle in danger, it likely never would.

The same pattern preceded the shuttle Challenger accident in 1986 when NASA managers ignored warnings that problems with O-rings on the shuttle's solid fuel-rocket boosters posed a hazard. Challenger was destroyed shortly after liftoff when an O-ring failed.

"You have a culture at the agency that historically has turned a deaf ear to (those types of) complaints and concerns," said space historian Frank Sietzen Jr., whose book "New Moon Rising" with co-author Keith Cowing examines the effort to remake NASA and redirect its mission toward the human space-exploration goals outlined by Bush.

NASA has tried to fix that weakness by aggressively promoting increased communication between the managers who make decisions and the engineers and other technical experts who advise them.

"This is a battle between managers and engineers," said Robert Zimmerman, author of several books on NASA and space exploration. Before the Columbia accident, the managers were in charge, Zimmerman said. But over the past two years, those tables have turned. "The managers have backed off and are letting the engineers do their thing," he said.

AP Workers prepare to close the hatch on the Italian-built multipurpose logistics module Raffaello at the Kennedy Space Center. The module will fly on space shuttle Discovery, carrying supplies to the international space station.

A call for dialogue

At NASA facilities across the country, new programs have been created to encourage discussions. At the mission-management team meeting room in Houston, staff members and advisers attending the sessions during the mission will be able to make comments at any time by speaking into one of several microphones that ring the room. At Kennedy Space Center in Florida, where Discovery will launch, workers who feel fatigued can take a break and be replaced by someone else without fear of punishment.

Other changes are more subtle.

When the mission-management team meets in Houston during the flight, the group's chairman will pause the discussion periodically to summarize the group's exchanges, said Chris Parker, a psychology professor at Northern Illinois University in DeKalb, who has spent more than a year helping the team develop better ways to operate. Those breaks should give team members and others in the room opportunities to voice their thoughts and concerns, he added.

Paul Hill, the lead flight director for the Discovery mission, said managers are doing everything they can to encourage engineers and others to express their opinions and concerns.

Astronaut Eileen Collins, who is commanding the Discovery mission, said the success of the changes also depends on front-line workers being willing to raise their voices.

"The culture of any organization is something that every single person is responsible for," she said. "Managers need to listen, but people also need to speak up."

Politicians in Washington also have a role to play in changing NASA's culture. Congress has a long history of neglecting the agency financially. At the same time, individual lawmakers often meddle in the agency's internal operations by fighting against resource shifts or work-force changes at NASA facilities located in their home districts.

NASA's ability to return astronauts to the moon and send them on to Mars largely depends on its ability to wind down the shuttle program over the next five years and shift financial resources to the new program. That will force many NASA centers to find new roles in the agency, and it could lead to the loss of jobs at some locations.

Already, lawmakers from Ohio have rallied against portions of NASA's newly proposed budget that shifts money away from aeronautics research — the study of flight inside Earth's atmosphere — at Glenn Research Center in Cleveland.

"If Congress fights (NASA budget shifts) as they traditionally have fought base closures, then you will never get a cultural change," said Sietzen, the historian. "Congress complained for years that NASA didn't have a vision, a clear mission. Now they do, but without the money."

The new vision for the space agency can become a reality only if NASA managers are freed from the parochial self-interests of Washington politicians, Sietzen said.

A troubling sign

Signs of NASA's old culture still surface.

Two weeks ago, Collins and some of her fellow Discovery astronauts said they didn't believe newly developed techniques for in-space repair of damaged orbiter tiles had been proved safe enough to risk an attempt to return the shuttle to Earth with a patch job. NASA managers, however, said they were confident some of the repairs could be relied on to bring the orbiter home safely. When questioned about the differing opinions, Hill said there was no guarantee that the crews' wishes would be honored if they objected to making a repair.

"If the crew absolutely does not agree with a decision that we make, we will talk about that," he said.

Zimmerman, the author, called Hill's response troubling, saying astronauts should have the last word concerning life-or-death decisions while they are in space.

"That's a red flag to me. It's a demonstration of where the problem still exists," he said.