Estimating the Distribution of the Sizes Of Flaws Remaining After an Inspection (Preprint)

Abstract

The U.S. Air Force plans for maintenance and retirement of aircraft based in part on fatigue crack growth models. Periodic inspections are used to help assess airworthiness and plan for future inspections. Nondestructive inspections are not perfect so some cracks are missed and the likelihood that an individual crack is detected is a function of the size of the crack when inspected. Additionally, the crack size distribution is related to the number of flight hours the aircraft has experienced, so not all inspection results come from the same distribution. In a recent study several models were compared that utilize the capability of the inspection system and the variation between aircraft and times of inspections to estimate the distribution of sizes of cracks that were missed during the inspection. This white paper summarizes those results and identifies some methods for extending them.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2006
Accession Number
ADA464707

Entities

People

  • Alan P. Berens
  • Jeremy Knopp
  • Peter W. Hovey

Organizations

  • University of Dayton

Tags

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Aircrafts
  • Data Science
  • Distribution Functions
  • Information Science
  • Inspection
  • Maintenance
  • Mathematics
  • Military Research
  • Normal Distribution
  • Probability
  • Probability Density Functions
  • Random Variables
  • Safety
  • Standards
  • Test And Evaluation

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