Practical Failure Analysis

, Volume 3, Issue 2, pp 59–69 | Cite as

Material-based failure analysis of a helicopter rotor hub

  • R. J. H. Wanhill
Peer Reviewed Articles


A Lynx helicopter from the Royal Netherlands Navy lost a rotor blade during preparation for take-off. The blade loss was due to failure of a rotor hub arm by fatigue. The arm was integral to the titanium alloy rotor hub. An extensive material-based failure analysis covered the hub manufacture, service damage, and estimates of service stresses. There was no evidence for failure due to poor material properties. However, fractographic and fracture mechanics analyses of the service failure, a full-scale test failure, and specimen test failures indicated that the service fatigue stress history could have been more severe than anticipated. This possibility was subsequently supported by a separate investigation of the assumed and actual fatigue loads and stresses.


fatigue helicopter rotor hub titanium alloy 


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Copyright information

© ASM International - The Materials Information Society 2003

Authors and Affiliations

  • R. J. H. Wanhill
    • 1
  1. 1.National Aerospace Laboratory NLRAmsterdamThe Netherlands

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