Generation of spectra and stress histories for fatigue and damage tolerance analysis of fuselage repairs

Details

• Creators:
  Broek, D ; Smith, S H ; Rice, R C
• Corporate Creators:
  Battelle Memorial Institute. Columbus Laboratories ; John A. Volpe National Transportation Systems Center (U.S.)
• Subject/TRT Terms:
  • Airframes
  • Airplanes
  • Fuselages
  • Maintenance
  • Fatigue
  • Maintenance and repair
• Publication/ Report Number:
  DOT-VNTSC-FAA-91-16
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Edition:
  Final report; March 1990-May 1991
• Corporate Publisher:
  United States. Department of Transportation. Federal Aviation Administration
• Abstract:
  This report describes a simplified procedure for the development of stress histories ; for use in the analysis of aircraft repairs.- Although repairs of all components of ; the airframe are of interest, this report concentrates on stress histories for ; fuselage skin repair, description of typical fuselage loadings is provided, and ; basic fuselage stress histories are described. A method for development of an ; exceedance diagram for analysis of fuselage skin repairs is detailed. Subsequently, a ; methodology for generating detailed stress histories is reviewed. Some of the key ; features are 1) the inclusion of a range of flights of different severities, 2) the ; inclusion of deterministic loads where they occur, e.g., ground-air-ground cycles, 3) ; the use of a near-optimum number of stress levels (10-16 positive and negative), 4) ; the combination of positive and negative excursions of equal frequency, and 5) ; matching of the total number of flights and cycles with the total exceedance diagram. ; Two methods of estimating fuselage skin stresses are presented, the first based on ; static equilibrium requirements and the second based on a limit load analysis. ; A comparison of the proposed history generation scheme with that of an airframe ; manufacturer for the KC-135 is also presented. The predicted fatigue crack growth ; patterns for a hypothetical through crack at a fastener hole are compared for the two ; history generation schemes at three areas within a fuselage. Predicted crack growth ; lives are within a factor of 1.5 for two of the three cases. For the third case ; (which is predicted to be the least severe by both techniques), the proposed scheme ; results in substantially longer crack growth life predictions. The probable reasons ; for these differences are discussed.
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• Format:
  PDF
• Funding:
  DTRS-57-89-C-00006
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/9085/dot_9085_DS1.pdf
• File Type:
  [PDF - 1.62 MB]
• Collection(s):
  Volpe Center
• Main Document Checksum:
  urn:sha-512:90d7cf1fd085fa19256171f0681b91ed9f604b90cbe3171c523d2dc2f824e7b59045d1aaec8967acda727657dfe041d4ce8c57e82207e98c13372165e574ab0c