How to Fix a NASA Disaster
The United States will have to decide whether it can afford safe human space flight
IMAGE: BRYAN CHRISTIE
One of the lines of inquiry followed by the Columbia Accident Investigation Board was testing to see if insulating foam could damage a shuttle wing. A piece of foam was fired at the leading edge of a wing [above], punching a 40-cm hole [inset].
NASA is broken. That's the fundamental message of the Columbia Accident Investigation Board's 248-page report, released on 26 August. ”The past decisions of national leaders--the White House, Congress, and NASA Headquarters--set the Columbia accident in motion,” states the report, which details how decisions in Washington, D.C., played as much a part in the loss of Columbia and her crew as the errant piece of foam that fatally damaged the spacecraft's left wing.
As for the foam, there can be no question that 81.7 seconds after launch, a chunk of foam designed to keep propellants in the shuttle's huge external tank at cryogenic temperatures broke free. With the shuttle still accelerating, the chunk crashed into the fragile leading edge of the left wing two-tenths of a second later, at some 877 km per hour. The resulting hole, approximately 25 cm across, remained undetected throughout the flight.
But upon reentry, superheated air rushed through the breach like a blowtorch, melting the wing's aluminum frame from within. With the Columbia traveling at Mach 19.5, aerodynamic forces tore the collapsing wing and then the entire shuttle apart.
That this chain of events can be stated with certainty is an amazing technical achievement, pieced together as it was from scattered debris, blurry photography, and radio telemetry. But by pursuing multiple independent lines of inquiry, ranging from studying computer simulations to examining the layers of molten metal found on recovered fragments of Columbia, the board was able to zero in on the foam and eliminate virtually all other possible causes of the shuttle's demise.
The 13-member board, led by retired Admiral Harold Gehman, was not content with just identifying the proximate cause of the disaster. In attempting to find out why the foam came off the tank and whether or not the deaths of the crew could have been prevented, it embarked on an investigation that led through a dysfunctional safety culture at NASA to, ultimately, the steps of Congress and the White House.
nnasa01.jpg ”NASA's safety culture has become reactive, complacent and dominated by unjustified optimism” is the report's blunt assessment of an agency laboring to meet its toughest schedule since President John F. Kennedy's mandate in 1961 to land on the moon before the decade was out. According to the report, as pressure to meet assembly deadlines for the International Space Station mounted, ”engineers found themselves in the unusual position of having to prove that the situation was unsafe--a reversal of the usual requirement to prove that a situation is safe.”
This pressure to conform arose because NASA programs had developed a built-in conflict of interest: the same people whose feet were being held to the fire to get projects completed on time and on budget were also made responsible for safety. When safety issues, such as the persistent problem of foam falling off the external tank, threatened to disrupt schedules or budgets, it was all too easy to finesse away problems rather than stop and address them.
In particular, a preference for studying problems with analysis and computer simulations rather than doing more expensive physical testing meant that many apparently reasonable engineering decisions were built on foundations of sand. In determining that the foam strike during Columbia's ascent would result in, at most, a minor ding, NASA relied on computer software that was being used to study ”a piece of debris that was 400 times larger” than the biggest sample it had ever been actually tested against, fumed the report.
As time went by and shuttles flew without major incident, finesse hardened into certainty--thus foam loss became not a critical problem outside the shuttle's proven safety envelope, but a familiar issue that meant nothing more than that some minor repairs would be needed after the shuttle returned to Earth.
When engineers--worried about the rosy picture painted by the computer analysis of the foam strike--asked for in-orbit imagery to be taken of Columbia's wing, they were refused because they could not prove that it was absolutely necessary. Bureaucracy triumphed over safety; the board found that ”management seemed more concerned about the staff following proper channels [in requesting images] than they were about the analysis.”
That NASA allowed a cancerous neglect of safety to metastasize across the agency was a consequence of the reorganizations and large workforce reductions that occurred during the 1990s as the agency struggled with a budget that remained flat, representing a 13 percent loss in actual purchasing power. This parsimonious funding came even as the U.S. government's finances blossomed during that same decade, leaving NASA to struggle with decaying facilities and an aging shuttle fleet.
The extent of the problem is illustrated by the board's description of the installation of netting inside the massive Vehicle Assembly Building at Cape Canaveral ”to prevent concrete from the building's ceiling from hitting the [shuttle]....NASA, the White House and Congress alike now face the specter of having to deal with years of infrastructure neglect.”
The buck stops here
And so the trail of the Columbia disaster ends with those who have ultimate responsibility for NASA--Congress and the White House. ”The White House and Congress must recognize the role of their decisions in this accident,” chastised the board. Not only did they fail to adequately fund the agency, but they also failed to provide leadership, leaving NASA without a clear vision of national space policy upon which it could build.
Nor did they provide oversight that could have corrected NASA's dying safety culture despite warning report after warning report from independent panels and task forces. Agency leaders would generally be brought before Congress to testify about budgets and schedules rather than safety--sending a clear signal as to what really counted when NASA's performance was being measured.
At press time, both the Senate and the House have embarked on an extensive series of hearings on the board's findings. Despite current economic difficulties, the board's indictment of 30 years of governmental neglect may finally loosen some purse strings. ”There's no question...if we wish to continue human space flight, we have to put more resources in,” said Congressman Sherwood Boehlert (R-N.Y.), the chair of the House Committee on Science, following the publication of the Columbia report. However, more has to be done than simply throwing money at the problem; if NASA supporters are ”expecting us to write a blank check, we're unwilling to do so,” he cautioned.
Indeed, it is clear that NASA must transform itself. But it cannot be trusted to do so by itself. ”The changes we recommend will be difficult to accomplish--and will be internally resisted,” said the board. The most difficult problem will be rooting out NASA's dysfunctional safety culture. ”Cultural problems are unlikely to be corrected without top-level leadership,” the board continues.
What this will mean in terms of concrete changes at NASA is yet unknown. Administrator Sean O'Keefe will likely stay in his post; the board noted many of the positive organizational changes he was making to get programs back under control before the Columbia disaster. But he must consider himself on probation and immediately set about installing new leaders throughout NASA who can, through personal example and decisive action, exorcise the agency's demons and restore NASA to its former glory. Otherwise, it is only a matter of time before the Columbia and Challenger disaster reports are joined by a third.