(SFOC COTR)

¶KSC Integration Office these areas, as well as in basic aerodynamic and thermodynamic research.

¶THE PROGRAMS Space Shuttle Space Shuttle

Space Shuttle Space Shuttle Space Shuttle Customer and Flight Processing (KSC) Systems Integration Office Projects Office (MSFC) Vehicle Engineering Office Integration Office

¶The two major human space flight efforts within NASA are the Space Shuttle Program and International Space Station Program, both headquartered at Missions Operations Flight Crew Operations Johnson although they report to a Dep- Directorate Directorate

¶Extravehicular Activity uty Associate Administrator at NASA Headquarters in Washington, D.C. The Space Shuttle Program Office at Solid Rocket Booster Reusable Solid Rocket Space Shuttle Main Engine External Tank (ET) Johnson is responsible for all aspects (SRB) Office Motor (RSRM) Office (SSME) Office Office of developing, supporting, and flying the Space Shuttle. To accomplish these tasks, the program maintains large workforces at the various NASA Centers that host the facilities used by the program. The Space Shuttle The Boeing Company, Rocketdyne Propulsion & Power Program Office is also responsible for managing the Space Flight The Rocketdyne Division of Rockwell International was responsi- Operations Contract with United Space Alliance that provides most ble for the development and manufacture of the Space Shuttle Main of the contractor support at Johnson and Kennedy, as well as a small Engines, and continues to support the engines as a part of The Boe- amount at Marshall. ing Company. The Space Shuttle Projects Office at Marshall manages the main engines contract, with most of the work performed in THE CONTRACTORS California, Stennis, and Kennedy.

¶The Space Shuttle Program employs a wide variety of commercial ATK Thiokol Propulsion companies to provide services and products. Among these are some ATK Thiokol Propulsion (formerly Morton-Thiokol) in Brigham of the largest aerospace and defense contractors in the country, in- City, Utah, manufactures the Reusable Solid Rocket Motor seg- cluding (but not limited to): ments that are the propellant sections of the Solid Rocket Boosters.

¶The Space Shuttle Projects Office at Marshall manages the Reus- United Space Alliance able Solid Rocket Motor contract. This is a joint venture between Boeing and Lockheed Martin that was established in 1996 to perform the Space Flight Operations Lockheed Martin Space Systems, Michoud Operations Contract that essentially conducts the day-to-day operation of the The External Tank was developed and manufactured by Martin Space Shuttle. United Space Alliance is headquartered in Houston, Marietta at the NASA Michoud Assembly Facility near New Or- Texas, and employs more than 10,000 people at Johnson, Kennedy, leans, Louisiana. Martin Marietta later merged with Lockheed to and Marshall. Its contract currently runs through 2005. create Lockheed Martin. The External Tank is the only disposable part of the Space Shuttle system, so new ones are always under The Boeing Company, NASA Systems construction. The Space Shuttle Projects Office at Marshall man- The Space Shuttle Orbiter was designed and manufactured by ages the External Tank contract. Rockwell International, located primarily in Downey and Palmdale, California. In 1996, The Boeing Company purchased the aerospace Lockheed Martin Missiles and Fire Control assets of Rockwell International, and later moved the Downey op- The Reinforced Carbon-Carbon (RCC) panels used on the nose eration to Huntington Beach, California, as part of a consolidation and wing leading edges of the Orbiter were manufactured by Ling- of facilities. Boeing is subcontracted to United Space Alliance to Temco-Vought in Grand Prairie, Texas. Lockheed Martin acquired provide support to Orbiter modifications and operations, with work LTV through a series of mergers and acquisitions. The Space Shuttle performed in California, and at Johnson and Kennedy. Program office at Johnson manages the RCC support contract.

¶Part One

¶"Building rockets is hard." Part of the problem is that space travel is in its infancy. Although humans have been launching orbital vehicles for almost 50 years now – about half the amount of time we have been flying airplanes – contrast the numbers. Since Sputnik, humans have launched just over 4,500 rockets towards orbit (not counting suborbital flights and small sounding rockets). During the first 50 years of aviation, there were over one million aircraft built. Almost all of the rockets were used only once; most of the airplanes were used more often.

¶There is also the issue of performance. Airplanes slowly built their performance from the tens of miles per hour the Wright Brothers initially managed to the 4,520 mph that Major William J. Knight flew in the X-15A-2 research airplane during 1967. Aircraft designers and pilots would slightly push the envelope, stop and get comfortable with where they were, then push on. Orbital rockets, by contrast, must have all of their performance on the first (and often, only) flight. Physics dictates this – to reach orbit, without falling back to Earth, you have to exceed about 17,500 mph. If you cannot vary performance, then the only thing left to change is the amount of payload – the rocket designers began with small payloads and worked their way up.

¶Rockets, by their very nature, are complex and unforgiving vehicles. They must be as light as possible, yet attain outstanding performance to get to orbit. Mankind is, however, getting better at building them. In the early days as often as not the vehicle exploded on or near the launch pad; that seldom happens any longer. It was not that different from early airplanes, which tended to crash about as often as they flew. Aircraft seldom crash these days, but rockets still fail between two-and-five percent of the time. This is true of just about any launch vehicle – Atlas, Delta, Soyuz, Shuttle – regardless of what nation builds it or what basic configuration is used; they all fail about the same amount of the time. Building and launching rockets is still a very dangerous

¶The Accident ing a space vehicle will ever be as routine an undertaking as commercial air travel – certainly not in the lifetime of anybody who reads this. The scientists and engineers continually work on better ways, but if we want to continue going into outer space, we must continue to accept the risks.

¶Part One of the report of the Columbia Accident Investigation Board is organized into four chapters. In order to set the background for further discussion, Chapter 1 relates the history of the Space Shuttle Program before the Challenger accident. The events leading to the original approval of the Space Shuttle Program are recounted, as well as an examination of some of the promises made in order to gain that approval. In retrospect, many of these promises could never have been achieved. Chapter 2 documents the final flight of Columbia. As a straightforward record of the event, it contains no findings or recommendations. Chapter 3 reviews five analytical paths – aerodynamic, thermodynamic, sensor data timeline, debris reconstruction, and imaging evidence – to show that all five independently arrive at the same conclusion. Chapter 4 describes the investigation into other possible physical factors that might have contributed to the accident, but were subsequently dismissed as possible causes.

¶Sunrise aboard Columbia on Flight Day 7.

¶business, and will continue to be so for the foreseeable future while we gain experience at it. It is unlikely that launch-

The Evolution of the Space Shuttle Program

¶More than two decades after its first flight, the Space Shuttle remains the only reusable spacecraft in the world capable of simultaneously putting multiple-person crews and heavy cargo into orbit, of deploying, servicing, and retrieving satellites, and of returning the products of on-orbit research to Earth. These capabilities are an important asset for the United States and its international partners in space. Current plans call for the Space Shuttle to play a central role in the U.S. human space flight program for years to come.

¶The Space Shuttle Programʼs remarkable successes, however, come with high costs and tremendous risks. The February 1 disintegration of Columbia during re-entry, 17 years after Challenger was destroyed on ascent, is the most recent reminder that sending people into orbit and returning them safely to Earth remains a difficult and perilous endeavor.

¶It is the view of the Columbia Accident Investigation Board that the Columbia accident is not a random event, but rather a product of the Space Shuttle Programʼs history and current management processes. Fully understanding how it happened requires an exploration of that history and management. This chapter charts how the Shuttle emerged from a series of political compromises that produced unreasonable expectations – even myths – about its performance, how the Challenger accident shattered those myths several years after NASA began acting upon them as fact, and how, in retrospect, the Shuttleʼs technically ambitious design resulted in an inherently vulnerable vehicle, the safe operation of which exceeded NASAʼs organizational capabilities as they existed at the time of the Columbia accident. The Boardʼs investigation of what caused the Columbia accident thus begins in the fields of East Texas but reaches more than 30 years into the past, to a series of economically and politically driven decisions that cast the Shuttle program in a role that its nascent technology could not support. To understand the cause of the Columbia accident is to understand how a program promis- ing reliability and cost efficiency resulted instead in a developmental vehicle that never achieved the fully operational

1.1 GENESIS OF THE SPACE TRANSPORTATION SYSTEM

¶The origins of the Space Shuttle Program date to discussions on what should follow Project Apollo, the dramatic U.S. missions to the moon.1 NASA centered its post-Apollo plans on developing increasingly larger outposts in Earth orbit that would be launched atop Apolloʼs immense Saturn V booster. The space agency hoped to construct a 12-person space station by 1975; subsequent stations would support 50, then 100 people. Other stations would be placed in orbit around the moon and then be constructed on the lunar surface. In parallel, NASA would develop the capability for the manned exploration of Mars. The concept of a vehicle – or Space Shuttle – to take crews and supplies to and from low-Earth orbit arose as part of this grand vision (see Figure 1.1-1). To keep the costs of these trips to a minimum, NASA intended to develop a fully reusable vehicle.2

¶Figure 1.1-1. Early concepts for the Space Shuttle envisioned a reusable two-stage vehicle with the reliability and versatility of a status NASA and the nation accorded it. commercial airliner.

¶NASAʼs vision of a constellation of space stations and jour- neying to Mars had little connection with political realities of the time. In his final year in office, President Lyndon Johnson gave highest priority to his Great Society programs and to dealing with the costs and domestic turmoil associated with the Vietnam war. Johnsonʼs successor, President Richard Nixon, also had no appetite for another large, expensive, Apollo-like space commitment. Nixon rejected NASAʼs ambitions with little hesitation and directed that the agencyʼs budget be cut as much as was politically feasible. With NASAʼs space station plans deferred and further production of the Saturn V launch vehicle cancelled, the Space Shuttle was the only manned space flight program that the space agency could hope to undertake. But without space stations to service, NASA needed a new rationale for the Shuttle. That rationale emerged from an intense three-year process of technical studies and political and budgetary negotiations that attempted to reconcile the conflicting interests of NASA, the Department of Defense, and the White House.3