Development and Automation of an Airframe Structural Analysis Methodology

Sammanfattning

The structural certification of transport category aircraft mandates a rigorous demonstration of static strength and stability for all primary load-carrying components. This thesis presents the development and validation of ASTRA (Airframe STRuctural Analysis), a computational framework designed to automate the transition from linear Global Finite Element Models (GFEM) to margins of safety for metallic semi-monocoque structures.ASTRA implements a hybrid analysis methodology applicable to any skin-stringer-frame assembly, integrating linear elastic internal loads with non-linear stability correlations. By capturing complex stiffened panel interactions ASTRA enables rapid identification of critical failure modes across large structural assemblies.The tool contributes to a more efficient, effective, and comprehensive airframe structural analysis, offering a faster and less error-prone approach than traditional methods. It helps identify the most critical regions, drives design decisions, and facilitates compliance demonstration. Additionally, ASTRA can assist in devising the structural load applicable at a given fuselage reference station by checking which are the maximum loads that yield positive margins of safety.Developed in a modular way, ASTRA allows each failure mode method to be used independently and can be further expanded to include new failure modes, alternative methods, and extensions to address more detailed FEMs, potentially broadening its scope significantly.