International Journal of Reliability, Risk and Safety: Theory and Application

International Journal of Reliability, Risk and Safety: Theory and Application

Integrated safety risks assessment of a low-pressure turbine section of an aero engine

Document Type : Original Research Article

Author
Aerospace research Institute, Ministry of Science, Research and Technology, Tehran, Iran
10.22034/IJRRS.2026.9.1.10
Abstract
Safety engineers aim to ensure that systems are designed, developed, and operated safely and reliably, in compliance with applicable regulations and standards. Safety is defined as the backbone of the aviation industry. To achieve and maintain the desired level of safety, risk analysis is a critical analytical tool. This scientific approach is employed to identify, evaluate, and manage hazards effectively. The primary objective of risk assessment techniques, in addition to ensuring compliance with legal requirements, is to mitigate operational risks and enhance overall safety. Engine failure constitutes a hazardous, emergent situation in aviation and aeronautical engineering, with the potential for severe consequences. While the low-pressure turbine section significantly influences the aviation safety of modern aircraft, this particular section has not received proportionate consideration. This paper addresses risk identification and management in the third and fourth stages of the low-pressure turbine in a JT8D engine. A framework is proposed for this purpose, utilizing historical failures' data, failure mode and effect analysis, and event tree analysis techniques. Both economic and technical effects are considered during the thorough investigation of hazards. Investigations have shown that blade shroud wear can cause vibration and fatigue, leading to blade fracture and engine cover rupture. Based on the safety risk assessment, some recommendations for inspection and maintenance procedures are suggested. Regularly inspecting, monitoring vibration, accurately measuring torque, and visiting shops are the recommended actions. Some airlines have conducted this procedure, and the experience shows that it effectively reduces the risk rate in the field.
Keywords
Subjects

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Volume 9, Issue 1
February 2026
Pages 139-147

  • Receive Date 25 November 2025
  • Revise Date 02 February 2026
  • Accept Date 08 February 2026