Accession Number : ADA331612

Title :   Development of Probabilistic Design Methodology for Composite Structures

Descriptive Note : Final rept. Jan-Dec 94

Corporate Author : VOUGHT AIRCRAFT CO DALLAS TX

Personal Author(s) : Gary, P. M. ; Riskalla, M. G.

PDF Url : ADA331612

Report Date : AUG 1997

Pagination or Media Count : 94

Abstract : This program was conducted by Vought Aircraft Company, Dallas, Texas, to perform technical studies to aid in the development of a probabilistic design methodology. The foundation of the probabilistic design approach, applied to composite structure, is to base design criteria and objectives on reliability targets instead of factors of safety. Control of the process, in terms of how much it differs from the traditional approach, is maintained by the "Probability of Structural Failure." The key technical issues addressed in this contract were the overall assessment of the accuracy of the methodology, current reliability experience, definition of appropriate goals, and database development. The overall assessment of the accuracy of the methodology was done by reviewing current published documents and papers in the probabilistic design field. This review focused on similarities and differences between approaches. The database development was done by visiting airline maintenance depots and naval aviation depots to collect data on structural failures. The analyses of such data produced historical values for aircraft structural reliability. Current structural reliability issues and reliability goals were addressed by analyzing the wing box of the Lear Fan aircraft using Vought's Probabilistic Design Model. Measures of structural reliability such as single flight hour probability of failure for the whole wing box, including upper skin, lower skin, and substructure were produced.

Descriptors :   *AIRCRAFT MAINTENANCE, *COMPOSITE STRUCTURES, *FAILURE(MECHANICS), METHODOLOGY, STRESS ANALYSIS, PROBABILITY, DESIGN CRITERIA, WING BOXES.

Subject Categories : Aircraft
      Statistics and Probability
      Terminal Flight Facilities

Distribution Statement : APPROVED FOR PUBLIC RELEASE