Exhibit 1201 ยท Investigation report
Columbia Accident Investigation Board Report, vol. 1, ch. 8: History as Cause: Columbia and Challenger
In all official engineering analyses and launch recommendations prior to the accidents, evidence that the design was not performing as expected was reinterpreted as acceptable and non-deviant, which diminished perceptions of risk throughout the agency.
Chapter 8 finds that foam strikes and O-ring erosion both followed one trajectory: an anomaly outside design specifications was accepted after the first incident, and later incidents were classed as routine. It attributes both accidents to organizational system effects and names Vaughan's term "normalization of deviance" (chapter 6, p. 130).
- Source
- Columbia Accident Investigation Board
- Date
- August 2003
- Quoted from
- Chapter 8, section 8.2, p. 196 (printed report page)
- Grade
- Primary record
- Document
- https://ntrs.nasa.gov/citations/20030093634
- Accessed
- 2026-11-10
- Cited by
- Findings citing this exhibit
- Note
- Quote read in the NASA NTRS full text of Volume I and cross-read in the chapter PDF mirrored at globalsecurity.org. Same chapter: "History is cause." (p. 195); "Because ill-structured problems are less visible and therefore invite the normalization of deviance, they may be the most risky of all." (p. 203).