Maintenance and inspection as risk factors in helicopter accidents: Analysis and recommendations

In this work, the authors establish that maintenance and inspection are a risk factor in helicopter accidents. Between 2005 and 2015, flawed maintenance and inspection were causal factors in 14% to 21% of helicopter accidents in the U.S. civil fleet. For these maintenance-related accidents, the authors examined the incubation time from when the maintenance error was committed to the time when it resulted in an accident. The authors found a significant clustering of maintenance accidents within a short number of flight-hours after maintenance was performed. Of these accidents, 31% of these accidents occurred within the first 10 flight-hours. This is reminiscent of infant mortality in reliability engineering, and the authors characterized it as maintenance error infant mortality. The last quartile of maintenance-related accidents occurred after 60 flight-hours following maintenance and inspection. The authors then examined the “physics of failures” underlying maintenance-related accidents and analyzed the prevalence of different types of maintenance errors in helicopter accidents. The authors found, for instance, that the improper or incomplete (re)assembly or installation of a part category accounted for the majority of maintenance errors with 57% of such cases, and within this category, the incorrect torquing of the B-nut and incomplete assembly of critical linkages were the most prevalent maintenance errors. The authors also found that within the failure to perform a required preventive maintenance and inspection task category, the majority of the maintenance programs were not executed in compliance with federal regulations, nor with the manufacturer maintenance plan. Maintenance-related accidents are particularly hurtful for the rotorcraft community, and they can be eliminated. This is a reachable objective when technical competence meets organizational proficiency and the collective will of all the stakeholders in this community. The authors conclude with a set of recommendations based on their findings, which borrow from the ideas underlying the defense-in-depth safety principle to address this disquieting problem.

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  • Supplemental Notes:
    • © 2019 Joseph Homer Saleh et al.
  • Authors:
    • Saleh, Joseph Homer
    • Ray, Archana Tikayat
    • Zhang, Katherine S
    • Churchwell, Jared S
  • Publication Date: 2019


  • English

Media Info

  • Media Type: Web
  • Features: Figures; References;
  • Serial:
  • Publication flags:

    Open Access (libre)

Subject/Index Terms

Filing Info

  • Accession Number: 01707577
  • Record Type: Publication
  • Files: TRIS
  • Created Date: May 28 2019 2:49PM