Journal of Failure Analysis and Prevention

, Volume 13, Issue 3, pp 359–367 | Cite as

Failure Analysis of a Jet Engine Gearbox Drive Gearshaft Ball Bearing

  • Rodolfo Villa
  • Scot Roswurm


The case study presented in this article details the failure investigation of an M50 alloy steel bearing used in a jet engine gearbox drive assembly. It discusses the investigative steps and analytic tools used to determine the root cause, highlighting the importance of continuous, thorough questioning by the investigating activity. The combined analyses demonstrated that the bearing failed by a single event overload as evidenced by bulk deformation and traces of foreign material on the rolling elements. The anomalous transferred metal found on the rolling elements subsequently led to the discovery of overlooked debris in an engine chip detector, and thus resulted in a review of several maintenance practices.


M50 Bearing Overload Foreign material 


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Copyright information

© ASM International 2013

Authors and Affiliations

  1. 1.Metallurgical Analysis SectionTinker AFBOklahoma CityUSA

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