Open Access Peer-reviewed Research Article

Comparison of aero engine component lifing methods

Main Article Content

Ashley Whitney-Rawls
Paul Copp
Jace Carter
Tarun Goswami corresponding author


Failure of critical engine components such as compressor, fan, and turbine disks during flight can cause the loss of the engine, aircraft, or even life. To reduce the risk of this failure during flight, different methodologies and tools have been developed to determine the safe operating life of these critical disk components. The two most widely used lifing methods, safe-life and damage tolerance, are inherently conservative, retiring all components when a predetermined operating limit is reached. Both methods retire components with theoretical useful life remaining. Additional lifing methods can be used to reduce this conservatism and extend the life of these components. Retirement for cause, developed within the United States Air Force is a lifing method that can extend the life of components by retiring a component only when there is cause to do so. Military and industry standards on lifing methodologies were reviewed. Both deterministic and probabilistic approaches to disk lifing methods are discussed as well as current tools. This paper provides a comparison of the methodologies and tools currently being used today by both the government and industry.

gas turbine disk components, lifing methods, damage tolerance, crack propagation, inspection interval

Article Details

Supporting Agencies
USAF, FAA, SWRI, OEMs and other organizations provided support of this activities.
How to Cite
Whitney-Rawls, A., Copp, P., Carter, J., & Goswami, T. (2022). Comparison of aero engine component lifing methods. Materials Engineering Research, 4(1), 201-222.


  1. Ejaz N, Salam I and Tauqir A. An Air Crash Due to Failure of Compressor Rotor. Engineering Failure Analysis, 2007, 14: 831-840.
  2. FAA 33.70. Engine Life Limited Part Rule Dec 10, 2008.
  3. United States Department of Defense Engine Structural Integrity Program.
  4. Millwater H, Enright M and Fitch S. Convergent Zone-Refinement Method for Risk Assessment of Gas Turbine Disks Subject to Low-Frequency Metallurgical Defects. Journal of Engineering for Gas Turbine and Power, 2007, 129(3): 827-835
  5. Melis M and Zaretsky E. Probabilistic Analysis of Aircraft Gas Turbine Disk Life and Reliability. Journal of Propulsion and Power, 1999, 15(5): 658-668.
  6. Immarigeon JP, Koul AK, Beres W, et al. The Aging of Engines: An Operator’s Perspective. aging of engines an operators perspective, 2000.
  7. Immarigeon JP, Beres W, Au P, et al. Life Cycle Management Strategies for Aging Engines. life cycle management strategies for aging engines, 2003.
  8. Wicks BJ, Antoniou RA, Slater SL, et al. The Inadequacy of Safe-Life Prediction: Aero-Engine Fan and Compressor Disk Cracking. NATO-RTO-MP-079(1), Lecture Series October, 2001.
  9. Vukelich S. Engine Life Extension Through the Use of Structural Assessment, Non- Destructive Inspection, and Material Characterization. NATO-RTO-MP-079(11), Lecture Series October, 2001.
  10. Damage Tolerance of Hole Features in High-Energy Turbine Engine Rotors. Federal Aviation Administration Advisory Circular 33.70-2.
  11. Forsberg F. Probabilistic Assessment of Failure Risk in Gas Turbine Discs. Linkoping University Institute of Technology.
  12. Zaretsky E and Hendricks R. Weibull-Based Methodology for Rotating Structures in Aircraft Engines. International Journal of Rotating Machinery, 2003, 9: 313-325.
  13. Chamis C. Damage Tolerance and Reliability of Turbine Engine Components. NATO-RTO-MP- 079(20), Lecture Series October, 2001.
  14. Pishva MR, Koul AK, Bellinger NC, et al. Service-Induced Damage In Turbines Discs and its Influence On Damage Tolerance-Based Life Prediction. Carleton University and the National Aeronautical Establishment.
  15. Leverant GR, Millwater HR, Mcclung RC, et al. A New Tool for Design and Certification of Aircraft Turbine Rotors. Journal of Engineering for Gas Turbines and Power, 2004, 126(1): 155-159.
  16. Tong YC, Hou J, Antoniou RA, et al. Probabilistic Damage Tolerance Assessment: The Relative Merits of DARWIN, NERF and PROF, 2005.
  17. Enright MP, Huyse L, M Cc Lung RC, et al. Probabilistic Methodology for Life Prediction of Aircraft Turbine Rotors. american society of civil engineers, 2004.
  18. Cesare MA and Sues RH. ProFES probabilisitc finite element system - Bringing probabilistic mechanics to the desktop, 1999.
  19. Tschirne KU and Holzbecher W. Cost Effectiveness of Modern Lifing Concepts. NATO-RTO-MP- 079(2), Lecture Series, October 2001.
  20. Harter J. AFGROW User’s Guide and Technical Manual. Air Force Research Laboratory Wright Patterson Air Force Base, 2008.
  21. The Application of 3D Finite Element Analysis to Engine Life Prediction. Aeromat Conference, 2001.
  22. United States Department of Defense Propulsion System Integrity Program.
  23. Copp P. United States Air Force Understanding and Applying United States and European Airworthiness Criteria. Wright State University, 2009.
  24. Goswami T and Harrison G. Role of Defects in Gas Turbine Disk Lifing Philosophies.
  25. Goswami T. Hot Section Disk Lifing Philosophies. International Gas Turbine and Aeroengine Congress and Expostion, May 1993.
  26. Choi SK, Canfield RA and Grandhi R. Reliability-based Structural Design. Springer London, 2007.
  27. Koul A and Wallace W. Importance of Physics-based Prognosis for Improving Turbine Reliability Part 2: A Turbine Disc Case Study in a Fleet Environment. Life Prediction Technologies Inc.
  28. Hudak Jr S, Enright M, McClung R, et al. A Probabilistic Analysis of In- Service Fatigue Damage Monitoring for Turbine Engine Prognosis. AIAA 2004-1953.
  29. Nahm SH, Suh CM, Jung MW, et al. Application of Damage Tolerance Approach for Turbine Disk Life Extension. International Journal of Modern Physics B, 2008, 17(8-9): 1916-1921.
  30. Harrison G. Translation of Service Usage into Component Life Consumption.
  31. Millwater HR and Osborn RW. Probabilistic Sensitivities for Fatigue Analysis of Turbine Engine Disks. International Journal of Rotating Machinery, 2006, 2006(12): 1-12.
  32. Kappas J. Review of Risk and Reliability Methods for Aircraft Gas Turbine Engines. DSTO-TR- 13006.
  33. Kiang R. Critical Part Life Extension Efforts in a Military Engine. NATO-RTO-MP- 079(1), Lecture Series, October 2001.
  34. Brockman RA, Huelsman MA and John R. Simulation of Deformation Modes for Damage Detection in Turbine Engine Disks. new zealand plant protection.
  35. Enright MP, Hudak SJ, Mcclung RC, et al. Application of Probabilistic Fracture Mechanics to Prognosis of Aircraft Engine Components. Aiaa Journal, 2006, 44(2): 311-316.
  36. Koul AK, Bellinger NC and Gould G. Damage-tolerance-based life prediction of aeroengine compressor discs: II. A probabilistic fracture mechanics approach. International Journal of Fatigue, 1990, 12(5): 388-396.
  37. Ugural A and Fenster S. Advanced Strength and Applied Elasticity. 4th Edition, 2003.
  38. Timbrell C, Claydon P and Cook G. Application Of ABAQUS To Analysis Of 3D Cracks And Fatigue Crack Growth Prediction.
  39. Jameel A. Surface Damage Tolerance Analysis of Gas Turbine Engine Rotor. ASME Turbo Expo, 2005.
  40. Southwest Research Institute. DARWIN 6.1 User’s Manual, 2008.
  41. Southwest Research Institute. DARWIN 6.1 Theory Manual, 2008.
  42. Have AT. Cold Turbistan; final definition of a standarized fatigue test loading sequence for tactical aircraft cold section engine discs. National Aerospace Laboratory Nlr, 1987.
  43. Have AA, Evans WJ, Have T, et al. TURBISTAN, A Standard Load Sequence for Aircraft Engine Discs. National Aerospace Laboratory The Netherlands, 1985.