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Materials with a honeycomb structure have a cellular geometry, which reduces the amount of material used to achieve mass perfection of the finished structure. Due to the widespread application of honeycomp composite materials (structures), the need for developing the design methods exists. It is especially important to have design methods to guarantee the longevity and reliability of the elements of aviation structures during the exploitation. The peculiarities of operation such complicated elements as honey comb require consideration of existing of tough and soft layers, which work differently. The equations of motion of the three-layer plate with honeycomp filling are given. Some important issues of investigation based on this equation are described. In the paper, the questions of destructive and non-destructive diagnostics of composite constructions are discussed.

The experimental test results of glued-mechanical couplings of shaft — bush made with the use of anaerobic sealants are presented. Quantitative estimations of the surface layer quality of the mating parts were obtained that made possible to estimate values of surface waviness of the shaft and the bush. The methodology of the waviness determination of cylindrical couplings is described. The influence of fit on mechanical strength of the shaft — bush coupling depending on properties of a used anaerobic sealant was established.

The design of modern technology is associated with increased requirements for strength and manufacturability. Press fit connections of small size parts can withstand significant workloads, so they are widely used in mechanisms and machines. Traditionally, the calculation of press fit connections is performed according to classical formulas using a large amount of reference data. The calculations use standard recommendations that make it easier to obtain solutions with a minimum investment of time. However, the time saving limits the search to a few joints, which are not always the best in some indicators. Modeling press fit joints with different combinations of parameters leads to the formation of hundreds of potential joints. To check their performance, it is necessary to use modern computing facilities. The computer has almost unlimited possibilities for computing speed and storing arrays of information. Simulation of press fit connections on a computer allows obtaining regression metamodels, accessing the statistical significance of parameters, and determining the area of workable connections. It becomes possible to optimize the design of the joint in terms of strength, weight and assembly technology. The system for calculating and statistical analysis of press fit connections has been developed on the basis of existing standards. A program has been developed providing the joints formation and verification with an assessment of their suitability for the specified requirements.

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