Story summary.A plane crash 6 months ago is one of the several where, in spite of a very thorough investigation that picked up many interesting tidbits, there is no clue to what might have caused the crash. A chance remark by the wife of Bob Kessler, the investigator of current crash, may be ... holds a clue...
Fact sheet.First published: Analog, September 1963.
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Among the stories from Astounding/Analog issues edited by John Campbell.