Probability of Detection (POD) Analysis for the Advanced Retirement for Cause (RFC)/Engine Structural Integrity Program (ENSIP) Nondestructive Evaluation (NDE) System-Volume 1: Pod Analysis

Abstract

In 1995, the U.S. Air Force initiated a multifaceted program to upgrade the ECIS. Planned changes to the ECIS include updating a) the eddy current instrument, b) the station computer and its operating system, and c) the robotics controller. These system changes were to be "drop-in" to avoid the costs of repeating a complete capability demonstration program for ongoing engine inspections. In addition, a new approach to calibration was demonstrated, and a new POD computer program was written for the analysis of data from capability demonstrations. This report presents the results of the study whose objectives were updating the POD analysis program and evaluating the data collected to demonstrate the drop-in compatibility of the upgraded and original ECISs. An additional task was later added to analyze data from an experiment designed to validate two proposed methods for inferring the POD of a geometry material combination using inspection results from other geometry/material combinations. While the primary focus of this study was POD analysis for the kFC/ENSIP application with its highly automated ECIS, the POD analysis methods are applicable to a broad range of nondestructive evaluation (NDE) systems. Accordingly, the report discusses POD analyses in this broader context.