Flaw Tolerant Safe-Life Methodology

Abstract

Conventional safe-life methodology has been in general use in the helicopter industry for more than 40 years to substantiate fatigue-loaded dynamic components. However, it is seen to need improvement. One improvement is to reduce its sensitivity to the strength-reducing effects of flaws and defects that may occur in manufacturing and service use. Damage Tolerance methodology provides a means to accomplish this improvement but it is currently difficult to economically apply it to every fatigue mode on every component. Flaw Tolerant methodology is an available equal-choice option to Damage Tolerance for Transport Category civil rotorcraft, and it is offered here as a practical improvement to conventional safe life for military applications as well. Flaw Tolerance, which is based on the characteristics of initiation of cracks from flaws, is described and illustrated by means of examples of successful applications to helicopter components. This paper provides a description and examples of successful applications of Flaw Tolerance.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 2000
Accession Number
ADP010645

Entities

People

  • D. O. Adams

Organizations

  • Sikorsky Aircraft Corporation

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Aircraft Equipment
  • Aircrafts
  • Airframes
  • Airworthiness
  • Cold Working
  • Damage Tolerance
  • Elements
  • Engineering
  • Flight Loads
  • Helicopters
  • Maintenance
  • Materials
  • Rotary Wing Aircraft
  • Surface Finishing
  • Test And Evaluation
  • Vehicles
  • Visual Inspection

Readers

  • Structural Health Monitoring of Composite Structures.
  • Systems Analysis and Design