Development of Supplemental Inspection Report for the Fairchild Metro SA226 and SA227 Airplane

This document is the final report covering the results of a 3-year program entitled Development of a Supplemental Inspection Document for A226SA227 Aircraft. The program focused on developing a supplemental inspection document SID for all variants of the SA226 and SA227 based on damage tolerance analysis techniques. The SA226 and SA227 were designed and certified prior to the advent of modern damage tolerance analysis or FAR amendments, which require the aircraft structure to meet damage tolerance requirements. A major portion of this study consisted of collecting the data and performing the analysis necessary to establish an inspection program based on current damage tolerance methodology. Material and component tests, service experience, strain surveys, stress analysis, and fracture mechanics tools were all utilized to establish this program, which provides inspections and modifications necessary to help ensure the continued structural integrity of the airplane. These items were accomplished and the SID was developed.