The strength and load-bearing capacity analyses results for flying vehicle typical structural elements and joints are presented in the paper. Calculations were made with the use of nonlinear finite element method, implemented in software NASTRAN and ABAQUS. Structural composite panels and metal-composite joints in attachment points of moving components under consideration for research. Employed computational models and procedures, obtained results analysis process are presented. Numerical strength estimations of structural panels and joint strength confirmed with test results. On the example of a virtual test simulation of composite panels’ strength test in a shear frame, the effect of experimental conditions on obtaining results is evaluated. It is shown that boundary conditions realized in such tests cannot always give correct values of panels’ global buckling critical stress. The computation results of buckling and strength of metal-composite joints in attachment points of moving components are presented. The computation performed on a detailed model with employing solid elements and taking into account contact interaction between joint parts, geometrical and physical nonlinearities. Composite strength in bolted joints is made based on Nuismer criterion. The formed recommendations for improvement made it possible to avoid earlier failure of the considered joint in strength tests.

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Annotation One of the main problem on the way to the effective integration of polymer composite materials in aircrafts’ primary structures is the high sensitivity to various defects and damages. The main task in design is to create a composite aircraft structure such that any possible damage (defect) does not lead to a decrease in its load-bearing capacity below the limited load level. As a rule, in practice, this problem is solved by performing a large number of tests. The introduction of a “Building Block” approach based on modern numerical methods will reduce the required number of tests. In this paper, we consider the nonlinear numerical analysis to estimate the residual load-bearing capacity of a composite structure. It allows taking into account different progressive failure processes and their interaction within a single model. On an example of the composite panel with a “cut” it is shown that this method results in a sufficiently accurate residual strength prediction. However, due to its complexity, it is unsuitable at the early stages of design development. For this task, we developed a simplified numerical analysis method. The obtained results validated by comparison with the available test data and with more detailed nonlinear analysis.