Feynman's "Personal observations on the reliability of the Shuttle" [1] might help understand why this is so. Down in the "avionics" section. [1] http://www.fo

Feynman's "Personal observations on the reliability of the Shuttle" [1] might help understand why this is so. Down in the "avionics" section. [1] http://www.fotuva.org/feynman/challenger-appendix.html http://www.fotuva.org/feynman/challenger-appendix.html