Changes

NASA had said the O-rings had a safety factor of 3, which [[Richard Feynman]] later exposed as untrue.

NASA had said the O-rings had a safety factor of 3, which [[Richard Feynman]] later exposed as untrue.

* SRB engineers had previously warned about problems in the o-rings, but had been dismissed by NASA management.<ref> [http://duartes.org/gustavo/blog/post/richard-feynman-challenger-disaster-software-engineering Richard Feynman, the Challenger Disaster, and Software Engineering]</ref>

* [[SRB]] engineers had previously warned about problems in the o-rings, but had been dismissed by NASA management.<ref> [http://duartes.org/gustavo/blog/post/richard-feynman-challenger-disaster-software-engineering Richard Feynman, the Challenger Disaster, and Software Engineering]</ref>

* For example. in determining if flight 51-L was safe to fly in the face of ring erosion in flight 51-C, it was noted that the erosion depth was only one-third of the radius. It had been noted in an experiment cutting the ring that cutting it as deep as one radius was necessary before the ring failed. Instead of being very concerned that variations of poorly understood conditions might reasonably create a deeper erosion this time, it was asserted, there was "a safety factor of three." This is a strange use of the engineer's term, "[[safety factor]]."<ref> [http://www.ralentz.com/old/space/feynman-report.html Feynman's Appendix to the Rogers Commission Report on the Space Shuttle Challenger Accident]</ref>

* For example. in determining if flight 51-L was safe to fly in the face of ring erosion in flight 51-C, it was noted that the erosion depth was only one-third of the radius. It had been noted in an experiment cutting the ring that cutting it as deep as one radius was necessary before the ring failed. Instead of being very concerned that variations of poorly understood conditions might reasonably create a deeper erosion this time, it was asserted, there was "a safety factor of three." This is a strange use of the engineer's term, "[[safety factor]]."<ref> [http://www.ralentz.com/old/space/feynman-report.html Feynman's Appendix to the Rogers Commission Report on the Space Shuttle Challenger Accident]</ref>