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Part Two Why the Accident Occurred COLUMBIA ACCIDENT INVESTIGATION BOARD Part Two Why The Accident Occurred Many accident investigations do not go far enough. They vehicle called the Space Shuttle. When the agency did this, identify the technical cause of the accident, and then connect it accepted the bargain to operate and maintain the vehicle it to a variant of “operator error” – the line worker who forgot in the safest possible way. The Board is not convinced that to insert the bolt, the engineer who miscalculated the stress, NASA has completely lived up to the bargain, or that Con- or the manager who made the wrong decision. But this is sel- gress and the Administration has provided the funding and dom the entire issue. When the determinations of the causal support necessary for NASA to do so. This situation needs to chain are limited to the technical flaw and individual failure, be addressed – if the nation intends to keep conducting hu- typically the actions taken to prevent a similar event in the fu- man space flight, it needs to live up to its part of the bargain. ture are also limited: fix the technical problem and replace or retrain the individual responsible. Putting these corrections in Part Two of this report examines NASAʼs organizational, place leads to another mistake – the belief that the problem is historical, and cultural factors, as well as how these factors solved. The Board did not want to make these errors. contributed to the accident. As in Part One, this part begins with history. Chapter 5 examines the post-Challenger his- Attempting to manage high-risk technologies while mini- tory of NASA and its Human Space Flight Program. This mizing failures is an extraordinary challenge. By their includes reviewing the budget as well as organizational and nature, these complex technologies are intricate, with many management history, such as shifting management systems interrelated parts. Standing alone, the components may be and locations. Chapter 6 documents management perfor- well understood and have failure modes that can be antici- mance related to Columbia to establish events analyzed in pated. Yet when these components are integrated into a larg- later chapters. The chapter reviews the foam strikes, intense er system, unanticipated interactions can occur that lead to schedule pressure driven by an artificial requirement to de- catastrophic outcomes. The risk of these complex systems is liver Node 2 to the International Space Station by a certain increased when they are produced and operated by complex date, and NASA managementʼs handling of concerns regard- organizations that also break down in unanticipated ways. ing Columbia during the STS-107 mission. In our view, the NASA organizational culture had as much In Chapter 7, the Board presents its views of how high-risk to do with this accident as the foam. Organizational culture activities should be managed, and lists the characteristics refers to the basic values, norms, beliefs, and practices that of institutions that emphasize high-reliability results over characterize the functioning of an institution. At the most ba- economic efficiency or strict adherence to a schedule. This sic level, organizational culture defines the assumptions that chapter measures the Space Shuttle Programʼs organizational employees make as they carry out their work. It is a powerful and management practices against these principles and finds force that can persist through reorganizations and the change them wanting. Chapter 7 defines the organizational cause and of key personnel. It can be a positive or a negative force. offers recommendations. Chapter 8 draws from the previous chapters on history, budgets, culture, organization, and safety In a report dealing with nuclear wastes, the National Re- practices, and analyzes how all these factors contributed to search Council quoted Alvin Weinbergʼs classic statement this accident. This chapter captures the Boardʼs views of the about the “Faustian bargain” that nuclear scientists made need to adjust management to enhance safety margins in with society. “The price that we demand of society for this Shuttle operations, and reaffirms the Boardʼs position that magical energy source is both a vigilance and a longevity of without these changes, we have no confidence that other our social institutions that we are quite unaccustomed to.” “corrective actions” will improve the safety of Shuttle opera- This is also true of the space program. At NASAʼs urging, the tions. The changes we recommend will be difficult to accom- nation committed to building an amazing, if compromised, plish – and will be internally resisted. Report Volume I August 2003 9 7 COLUMBIA COLUMBIA ACCIDENT INVESTIGATION BOARD ACCIDENT INVESTIGATION BOARD 9 8 Report Volume I August 2003 Report Volume I August 2003 9 9 COLUMBIA COLUMBIA ACCIDENT INVESTIGATION BOARD ACCIDENT INVESTIGATION BOARD CHAPTER 5 From Challenger to Columbia The Board is convinced that the factors that led to the operate the Space Shuttle. While it would be inaccurate to Columbia accident go well beyond the physical mechanisms say that NASA managed the Space Shuttle Program at the discussed in Chapter 3. The causal roots of the accident can time of the Columbia accident in the same manner it did prior also be traced, in part, to the turbulent post-Cold War policy to Challenger, there are unfortunate similarities between the environment in which NASA functioned during most of the agencyʼs performance and safety practices in both periods. years between the destruction of Challenger and the loss of Columbia. The end of the Cold War in the late 1980s meant 5.1 THE CHALLENGER ACCIDENT that the most important political underpinning of NASAʼs AND ITS AFTERMATH Human Space Flight Program – U.S.-Soviet space competi- tion – was lost, with no equally strong political objective to The inherently vulnerable design of the Space Shuttle, replace it. No longer able to justify its projects with the kind described in Chapter 1, was a product of policy and tech- of urgency that the superpower struggle had provided, the nological compromises made at the time of its approval in agency could not obtain budget increases through the 1990s. 1972. That approval process also produced unreasonable Rather than adjust its ambitions to this new state of affairs, expectations, even myths, about the Shuttleʼs future per- NASA continued to push an ambitious agenda of space formance that NASA tried futilely to fulfill as the Shuttle science and exploration, including a costly Space Station became “operational” in 1982. At first, NASA was able to Program. maintain the image of the Shuttle as an operational vehicle. During its early years of operation, the Shuttle launched sat- If NASA wanted to carry out that agenda, its only recourse, ellites, performed on-orbit research, and even took members given its budget allocation, was to become more efficient, of Congress into orbit. At the beginning of 1986, the goal of accomplishing more at less cost. The search for cost reduc- “routine access to space” established by President Ronald tions led top NASA leaders over the past decade to downsize Reagan in 1982 was ostensibly being achieved. That appear- the Shuttle workforce, outsource various Shuttle Program ance soon proved illusory. On the cold morning of January responsibilities – including safety oversight – and consider 28, 1986, the Shuttle Challenger broke apart 73 seconds into eventual privatization of the Space Shuttle Program. The its climb towards orbit. On board were Francis R. Scobee, programʼs budget was reduced by 40 percent in purchasing Michael J. Smith, Ellison S. Onizuka, Judith A. Resnick, power over the past decade and repeatedly raided to make Ronald E. McNair, Sharon Christa McAuliffe, and Gregory up for Space Station cost overruns, even as the Program B. Jarvis. All perished. maintained a launch schedule in which the Shuttle, a de- velopmental vehicle, was used in an operational mode. In Rogers Commission addition, the uncertainty of top policymakers in the White House, Congress, and NASA as to how long the Shuttle On February 3, 1986, President Reagan created the Presiden- would fly before being replaced resulted in the delay of tial Commission on the Space Shuttle Challenger Accident, upgrades needed to make the Shuttle safer and to extend its which soon became known as the Rogers Commission after service life. its chairman, former Secretary of State William Rogers. The Commissionʼs report, issued on June 6, 1986, concluded that The Space Shuttle Program has been transformed since the the loss of Challenger was caused by a failure of the joint late 1980s implementation of post-Challenger management and seal between the two lower segments of the right Solid changes in ways that raise questions, addressed here and in Rocket Booster. Hot gases blew past a rubber O-ring in the later chapters of Part Two, about NASAʼs ability to safely joint, leading to a structural failure and the explosive burn- 9 8 Report Volume I August 2003 Report Volume I August 2003 9 9 COLUMBIA COLUMBIA ACCIDENT INVESTIGATION BOARD ACCIDENT INVESTIGATION BOARD ing of the Shuttleʼs hydrogen fuel. While the Rogers Com- mission identified the failure of the Solid Rocket Booster SELECTED ROGERS COMMISSION joint and seal as the physical cause of the accident, it also RECOMMENDATIONS noted a number of NASA management failures that contrib- uted to the catastrophe. • “The faulty Solid Rocket Motor joint and seal must be changed. This could be a new design eliminating The Rogers
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