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Its mission isunique, and its stunning technological accomplishments, asource of pride and inspiration without equal, represent thebest in American skill and courage. At times NASAʼs effortshave riveted the nation, and it is never far from public viewand close scrutiny from many quarters. The loss of Columbiaand her crew represents a turning point, calling for a renewedpublic policy debate and commitment regarding humanspace exploration. One of our goals has been to set forth theterms for this debate.Named for a sloop that was the first American vessel tocircumnavigate the Earth more than 200 years ago, in 1981Columbia became the first spacecraft of its type to fly in Earthorbit and successfully completed 27 missions over more thantwo decades.
During the STS-107 mission, Columbia and itscrew traveled more than six million miles in 16 days.The Orbiterʼs destruction, just 16 minutes before scheduledtouchdown, shows that space flight is still far from routine.It involves a substantial element of risk, which must berecognized, but never accepted with resignation. The sevenColumbia astronauts believed that the risk was worth thereward.
The Board salutes their courage and dedicates thisreport to their memory.August 2003COLUMBIAACCIDENT INVESTIGATION BOARDReport Volume IAugust 20037Columbia inside the Orbiter Processing Facility on November 20, 2002.COLUMBIAACCIDENT INVESTIGATION BOARDEXECUTIVE SUMMARYThe Columbia Accident Investigation Boardʼs independentinvestigation into the February 1, 2003, loss of the SpaceShuttle Columbia and its seven-member crew lasted nearlyseven months. A staff of more than 120, along with some 400NASA engineers, supported the Boardʼs 13 members. Investigators examined more than 30,000 documents, conductedmore than 200 formal interviews, heard testimony fromdozens of expert witnesses, and reviewed more than 3,000inputs from the general public.
In addition, more than 25,000searchers combed vast stretches of the Western United Statesto retrieve the spacecraftʼs debris. In the process, Columbiaʼstragedy was compounded when two debris searchers with theU.S. Forest Service perished in a helicopter accident.The Board recognized early on that the accident was probably not an anomalous, random event, but rather likely rooted to some degree in NASAʼs history and the human spaceflight programʼs culture. Accordingly, the Board broadenedits mandate at the outset to include an investigation of a widerange of historical and organizational issues, including political and budgetary considerations, compromises, and changing priorities over the life of the Space Shuttle Program.
TheBoardʼs conviction regarding the importance of these factorsstrengthened as the investigation progressed, with the resultthat this report, in its findings, conclusions, and recommendations, places as much weight on these causal factors as onthe more easily understood and corrected physical cause ofthe accident.The physical cause of the loss of Columbia and its crew wasa breach in the Thermal Protection System on the leadingedge of the left wing, caused by a piece of insulating foamwhich separated from the left bipod ramp section of theExternal Tank at 81.7 seconds after launch, and struck thewing in the vicinity of the lower half of Reinforced CarbonCarbon panel number 8.
During re-entry this breach in theThermal Protection System allowed superheated air to penetrate through the leading edge insulation and progressivelymelt the aluminum structure of the left wing, resulting ina weakening of the structure until increasing aerodynamicforces caused loss of control, failure of the wing, and breakup of the Orbiter. This breakup occurred in a flight regime inwhich, given the current design of the Orbiter, there was nopossibility for the crew to survive.The organizational causes of this accident are rooted in theSpace Shuttle Programʼs history and culture, including theoriginal compromises that were required to gain approval forthe Shuttle, subsequent years of resource constraints, fluctuating priorities, schedule pressures, mischaracterization ofthe Shuttle as operational rather than developmental, and lackof an agreed national vision for human space flight.
Culturaltraits and organizational practices detrimental to safety wereallowed to develop, including: reliance on past success as asubstitute for sound engineering practices (such as testing tounderstand why systems were not performing in accordancewith requirements); organizational barriers that preventedeffective communication of critical safety information andReport Volume Istifled professional differences of opinion; lack of integratedmanagement across program elements; and the evolution ofan informal chain of command and decision-making processes that operated outside the organizationʼs rules.This report discusses the attributes of an organization thatcould more safely and reliably operate the inherently riskySpace Shuttle, but does not provide a detailed organizationalprescription.
Among those attributes are: a robust and independent program technical authority that has completecontrol over specifications and requirements, and waiversto them; an independent safety assurance organization withline authority over all levels of safety oversight; and an organizational culture that reflects the best characteristics of alearning organization.This report concludes with recommendations, some ofwhich are specifically identified and prefaced as “beforereturn to flight.” These recommendations are largely relatedto the physical cause of the accident, and include preventing the loss of foam, improved imaging of the Space Shuttlestack from liftoff through separation of the External Tank,and on-orbit inspection and repair of the Thermal Protection System.
The remaining recommendations, for the mostpart, stem from the Boardʼs findings on organizationalcause factors. While they are not “before return to flight”recommendations, they can be viewed as “continuing to fly”recommendations, as they capture the Boardʼs thinking onwhat changes are necessary to operate the Shuttle and futurespacecraft safely in the mid- to long-term.These recommendations reflect both the Boardʼs strong support for return to flight at the earliest date consistent with theoverriding objective of safety, and the Boardʼs convictionthat operation of the Space Shuttle, and all human spaceflight, is a developmental activity with high inherent risks.A view from inside the Launch Control Center as Columbia rolls outto Launch Complex 39-A on December 9, 2002.August 20039COLUMBIAACCIDENT INVESTIGATION BOARDColumbia sits on Launch Complex 39-A prior to STS-107.10Report Volume IAugust 2003COLUMBIAACCIDENT INVESTIGATION BOARDREPORT SYNOPSISThe Columbia Accident Investigation Boardʼs independentinvestigation into the tragic February 1, 2003, loss of theSpace Shuttle Columbia and its seven-member crew lastednearly seven months and involved 13 Board members,approximately 120 Board investigators, and thousandsof NASA and support personnel.
Because the events thatinitiated the accident were not apparent for some time,the investigationʼs depth and breadth were unprecedentedin NASA history. Further, the Board determined early inthe investigation that it intended to put this accident intocontext. We considered it unlikely that the accident was arandom event; rather, it was likely related in some degreeto NASAʼs budgets, history, and program culture, as wellas to the politics, compromises, and changing priorities ofthe democratic process. We are convinced that the management practices overseeing the Space Shuttle Program wereas much a cause of the accident as the foam that struck theleft wing.
The Board was also influenced by discussionswith members of Congress, who suggested that this nationneeded a broad examination of NASAʼs Human Space FlightProgram, rather than just an investigation into what physicalfault caused Columbia to break up during re-entry.Findings and recommendations are in the relevant chaptersand all recommendations are compiled in Chapter 11.Volume I is organized into four parts: The Accident; Whythe Accident Occurred; A Look Ahead; and various appendices. To put this accident in context, Parts One and Two beginwith histories, after which the accident is described and thenanalyzed, leading to findings and recommendations.
PartThree contains the Boardʼs views on what is needed to improve the safety of our voyage into space. Part Four is reference material. In addition to this first volume, there will besubsequent volumes that contain technical reports generatedby the Columbia Accident Investigation Board and NASA,as well as volumes containing reference documentation andother related material.PART ONE: THE ACCIDENTChapter 1 relates the history of the Space Shuttle Programbefore the Challenger accident. With the end looming forthe Apollo moon exploration program, NASA unsuccessfully attempted to get approval for an equally ambitious(and expensive) space exploration program.
Most of theproposed programs started with space stations in low-Earthorbit and included a reliable, economical, medium-liftvehicle to travel safely to and from low-Earth orbit. Aftermany failed attempts, and finally agreeing to what wouldbe untenable compromises, NASA gained approval from theNixon Administration to develop, on a fixed budget, onlythe transport vehicle.
Because the Administration did not approve a low-Earth-orbit station, NASA had to create a mission for the vehicle. To satisfy the Administrationʼs requirement that the system be economically justifiable, the vehiclehad to capture essentially all space launch business, and todo that, it had to meet wide-ranging requirements. TheseReport Volume Isometimes-competing requirements resulted in a compromise vehicle that was less than optimal for manned flights.NASA designed and developed a remarkably capable andresilient vehicle, consisting of an Orbiter with three MainEngines, two Solid Rocket Boosters, and an External Tank,but one that has never met any of its original requirementsfor reliability, cost, ease of turnaround, maintainability, or,regrettably, safety.Chapter 2 documents the final flight of Columbia.
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