Development of Damage Tolerance Methodology for Antenna Installations in Pressurized Aircraft

Sammanfattning: Modifying an aircraft must be done in a safe way such that the safe operation of the aircraft is not violated. Compliance must be shown towards certification and airworthiness regulations in order to install a modification and allow for commercial flight. Certification is a time-consuming process where damage tolerance analysis is a major part. The challenge for small and mid-sized companies is to simplify the damage tolerance methodology without diminishing the level of safety which is the top priority for aircraft operations. By utilizing proven methods and recommended theory with adequate conservatism, an mostly analysis-based methodology was developed which includes stress analysis, finite element methods and crack growth analysis. The resulting methodology provides the tools to estimate longitudinal and circumferential crack growth and the corresponding critical crack length that would cause a structural failure. This also enables the establishment of inspections intervals which are required for continued airworthiness.