Columbia Accident Investigation Board

Memorial emblem for the three U.S. human space flight accidents. Translation: "To The Stars, Through Adversity – Always Exploring"

The Columbia Accident Investigation Board (CAIB) was convened by NASA to investigate the destruction of the Space Shuttle Columbia during STS-107 upon atmospheric re-entry on February 1, 2003. The panel determined that the accident was caused by foam insulation breaking off from the shuttle, forming debris which damage the wing; and that the problem of "debris shedding" was well known but considered "acceptable" by management. The panel also recommended changes that should be made to increase the safety of future shuttle flights. The CAIB released its final report on August 26, 2003.

Major findings

The board found both the immediate physical cause of the accident and also what it called organizational causes.

Immediate cause of the accident

82 seconds after launch a large piece of foam insulating material from the external tank broke free and struck the leading edge of the shuttle's left wing, damaging the protective carbon heat shielding panels. This damage allowed super-heated gases to enter the wing structure during re-entry into the Earth's atmosphere and caused the destruction of the Columbia.

Organizational cause of the accident

The problem of debris shedding from the external tank was well known and had caused shuttle damage on every prior shuttle flight. The damage was usually, but not always, minor. Over time, management gained confidence that it was an acceptable risk. NASA decided that it did not warrant an extra EVA for visual inspection, feeling that it would be like hitting a piece of Styrofoam with your car as you were going down the highway.

Echoes of Challenger

One board member, Dr. Sally Ride, served on both the CAIB panel and Rogers Commission and noted remarkable similarities between the two tragedies. She questioned why the shuttle was allowed to continue flying with known problems that were, eventually, catastrophic.

Since no machine is perfect, the problem comes down to identifying which known problems are an acceptable risk and which are not. In these two examples, shedding foam and failing o-rings, the organization failed to react correctly to the seriousness of the problem: in both cases, whereas engineers recognized the seriousness of the problem, NASA management dismissed both the evidence and the engineers' expertise and ultimately decided to continue with the mission, with catastrophic results.

To illustrate the organizational problems of safety awareness, Richard Feynman attached a personal appendix to the Rogers Commission Report. It is equally relevant to the CAIB report. In it, he wrote: "It appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management. What are the causes and consequences of this lack of agreement? … we could properly ask, 'What is the cause of management's fantastic faith in the machinery?'"

The CAIB report found these same misperceptions by management and concluded that they contributed to the accident. Both reports also examined the ability of schedule pressures to influence safety-related design decisions.

Board recommendations

The board made 29 specific recommendations to NASA to improve the safety of future shuttle flights. These recommendations include:

• Foam from external tank should not break free
• Better pre-flight inspection routines
• Increase quality of images available of shuttle during ascent and on-flight
• Recertify all shuttle components by the year 2010
• Establish an independent Technical Engineering Authority that is responsible for technical requirements and all waivers to them, and will build a disciplined, systematic approach to identifying, analyzing, and controlling hazards throughout the life cycle of the Shuttle System.

In the meantime, only two further Space Shuttle missions are allowed to be flown before the implementation of these recommendations.

Shuttle program since the CAIB report

After the CAIB report came out, NASA implemented all recommended changes and flew its first post-Columbia mission in 2005. As part of the CAIB recommendations, the Shuttle carried a 50-foot inspection boom attached to the robot arm, which was used within 24 hours of launch to check the orbiter for damage. As all but one of the post-Columbia missions are concentrated on the International Space Station, primarily to provide a "safe haven" in the event an orbiter is damaged beyond the normal repair methods, NASA (smarting from a critical report that the STS-107 crew could have been rescued using the Space Shuttle Atlantis) implemented a STS-3xx contingency mission program that can launch a rescue orbiter on short notice, similar to the Skylab Rescue that was planned during the Skylab program.

NASA retired the Space Shuttle fleet on July 21, 2011 after completing the ISS and the final flight and subsequent landing of Space Shuttle Atlantis. The Shuttle's replacement, Orion, was to have consisted of an Apollo-derived spacecraft launched on the Ares I rocket, which would use a Space Shuttle Solid Rocket Booster as its first stage. Orion would not face the dangers of either an O-ring failure (due to the presence of a launch escape system) or shedding foam (as the spacecraft will be launched in a stack configuration). In addition to ferrying crews to the ISS, the Orion spacecraft was to (as part of Project Constellation) allow NASA to return to the Moon. President Obama signed the NASA Authorization Act 2010 on October 11 which officially brought the Constellation program to an end, replacing it with the Space Launch System (SLS) and Multi-Purpose Crew Vehicle (MPCV) programs to develop the launch vehicle and spacecraft to enable human exploration missions beyond low-Earth orbit.

Board members

Chairman of the board

• Admiral Hal Gehman, USN

Board members

• Rear Admiral Stephen Turcotte, Commander, Naval Safety Center
• Maj. General John Barry, Director, Plans and Programs, Headquarters Air Force Materiel Command
• Maj. General Kenneth W. Hess, Commander, Air Force Safety Center
• Dr. James N. Hallock, Chief, Aviation Safety Division, U.S. Department of Transportation, Volpe Center
• Mr. Steven B. Wallace, Director of Accident Investigation, Federal Aviation Administration
• Brig. General Duane Deal, Commander, 21st Space Wing, United States Air Force
• Mr. Scott Hubbard, Director, NASA Ames Research Center
• Mr. Roger E. Tetrault, Retired Chairman, McDermott International
• Dr. Sheila E. Widnall, Professor of Aeronautics and Astronautics and Engineering Systems, MIT
• Dr. Douglas D. Osheroff, Professor of Physics and Applied Physics, Stanford University
• Dr. Sally Ride, Professor of Space Science, University of California, San Diego
• Dr. John Logsdon, Director of the Space Policy Institute, George Washington University

Board support

• Ex-Officio Member: Lt. Col. Michael J. Bloomfield, NASA Astronaut
• Executive Secretary: Mr. Theron M. Bradley, Jr., NASA Chief Engineer

Partial list of additional investigators and CAIB support staff

• Col Timothy Bair
• Col. Jack Anthony
• Dr. James P. Bagian
• Lt. Col. Richard J. Burgess
• Thomas L. Carter
• Dr. Dwayne A. Day
• Major Tracy Dillinger
• Thomas L. Foster
• CDR Mike Francis
• Howard E. Goldstein
• Lt. Col Patrick A. Goodman
• Lt. Matthew E. Granger
• Ronald K. Gress
• Thomas Haueter
• Dr. Daniel Heimerdinger
• Dennis R. Jenkins
• Christopher Kirchhoff
• Dr. Gregory T. A. Kovacs
• John F. Lehman
• Jim Mosquera
• Gary Olson
• Gregory Phillips
• David B. Pye
• Lester A. Reingold
• Donald J. Rigali
• Dr. James. W. Smiley
• G. Mark Tanner
• Lt. Col. Wade J. Thompson
• Bob Vallaster
• Lt. Col. Donald J. White
• Dr. Paul D. Wilde
• LCDR Johnny R. Wolfe Jr.
• Richard W. Russell
• Dr. Robert E. Green, Jr.

See also

• Apollo 204 Review Board
• Rogers Commission

Sources

• CAIB panel and staff information Retrieved February 15, 2004
• CAIB Final Report, Volume 1 (August 26, 2003)
• STS-107 Investigation Reference Page
• NASA SLS MPCV Retrieved April 30, 2011

External links

• Columbia Accident Investigation Board homepage
• CAIB hearing transcripts
• NASA homepage