Acoustic Emission Monitoring of Crack Propagation on the Expedited Wing Fatigue Test Article (X993).

Abstract

This final report describes work accomplished, under USAF contract, whose objective was to evaluate the ability of acoustic emission techniques to detect crack growth in a large full-production aircraft wing fatigue test article subjected to simulated flight spectra. Fatigue cracks were propagated at seventeen selected pre-damaged fastener holes in eight test areas on the test article. The flight load spectra consisted of fifty variable tension-tension gust cycles followed by 1/2 of a compressive ground cycle. Sixteen of the fastener holes were monitored with a 32-channel acoustic emission flaw locator system containing a computer, CRT monitor, input/output teleprinter console and tape recorder. Linear and triangular sensor arrays were used to detect and locate cracks. Twelve fatigue cracks were detected at fifteen fastener holes monitored where crack growth occurred. Acoustic emission data were correlated to crack growth data, determined through fractographic analysis, for several of the test cracks. Complex structural features which were accommodated successfully for detection of AE across joints are described. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1976
Accession Number
ADA041107

Entities

People

  • Cliff D. Bailey
  • James M. Hamilton
  • William M. Pless

Organizations

  • Lockheed Martin

Tags

Communities of Interest

  • Air Platforms
  • Sensors

DTIC Thesaurus Topics

  • Acoustic Emissions
  • Air Force
  • Aircrafts
  • Computers
  • Contracts
  • Coordinate Systems
  • Detectors
  • Electron Microscopes
  • Frequency
  • Materials
  • Materials Laboratories
  • Measurement
  • Simulators
  • Test And Evaluation
  • Two Dimensional
  • Waveforms
  • Wing Boxes

Readers

  • Computer Science/Computer Engineering/Data Science/Digital Signal Processing.
  • Structural Health Monitoring of Composite Structures.