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

The Columbia Accident Investigation Board (CAIB) was convened by NASA to investigate the loss of the Space Shuttle Columbia on February 1, 2003. In addition to determining the cause of the accident, 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 tiles. 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. The board found that this should not have happened.

The shuttle organization is very large, and decision makers cannot embody all information. Organizational mechanisms are responsible for properly informing and guiding decision makers. The report placed equal weight on organizational failings as the cause of the accident.

Echos 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; why was the shuttle allowed to continue to fly 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 predict the seriousness of the problem.

To illustrate the organizational problems of safety awareness, Richard Feynman attached a personal appendix (http://history.nasa.gov/rogersrep/v2appf.htm) to the Rogers Commission Report. It is equally relevant to the CAIB report. In it he says;

"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 differences of perception, and that they contributed to the accident. Both reports also examined the ability of schedule pressures to influenced 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
• Rectify 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.

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, 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, Inc.
• Dr. Sheila 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 at 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 Chief Astronaut Instructor
• Executive Secretary: Mr. Theron Bradley, Jr., NASA Chief Engineer

Partial list of additional investigators and CAIB support staff

• 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
• 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.

External links

• CAIB homepage (http://www.caib.us)
• NASA homepage (http://www.nasa.gov/home/index.html)

References

• CAIB panel and staff information retrieved Feb. 15, 2004 from http://www.caib.us/board_members/default.html