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Failure Analysis of the WWVB Tower



Joseph D. McColskey, Christopher N. McCowan, Raymond L. Santoyo


A failure analysis was conducted on the collapse of the NIST WWVB tower. The analysis included mechanical testing, chemical analysis, and metallographic examination of the failed part. We ascertained that the underlying reason for the collapse was fatigue failure due to poor engineering design and improper specifications on the insulator pin. Based on our findings, we recommend new pins be fabricated using recommended engineering practices with particular attention paid to details such as tolerances, radii, material choice, and heat treatment procedures.
NIST Interagency/Internal Report (NISTIR) - 6619
Report Number


antenna, fatigue, fracture, insulator pin, support pin, tower


McColskey, J. , McCowan, C. and Santoyo, R. (2002), Failure Analysis of the WWVB Tower, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 21, 2024)


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Created August 1, 2002, Updated October 16, 2008