The article describes the study carried out by the authors of the use of parametric geometric models to reduce the complexity of the design of parts that follow the theoretical contour of the bearing surfaces of the aircraft. Also, an algorithm that allows eliminating the existing ad hoc concavity profile is considered.

Tests on the dependence of glues shear strength on: gluing temperature, keeping time before testing, cooling environment, surface roughness, surface conditions, temperature and time of drying on air and in drying oven were carried out to select proper thermoplastics to use as glues for connection of steel elements together. The highest shear strength was showed by the following materials: desmopan 150, antifriction polyamide PA 610-L-DM, impact-resistant glass-filled polyamide. Given results allow significantly expanding scope of application of polymers as gluing compositions.

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One of the main problems in the design of rigid bus in open switchgears is the problem of structural stabilization under the action of various dynamic loads. The implementation of rigid bus with large spans of tube showed a real risk of wind resonance for cylindrical tube structures (aeroelastic self-oscillations). This phenomenon is dangerous due to the fact that at low speeds of the wind flow, intensive oscillations of the tubes occur in the vertical plane, adding to the static loads an essential dynamic component. Its level is comparable with loads from its own weight of structures and can, in combination with other loads, will be the cause of stresses close to the limiting ones by the 1st group of limiting states. The problem of reducing the level of structural oscillations in many cases is associated with the need to increase rigidity and reduce the material consumption of structures, however, it is important to fulfil the technological requirements of the operating conditions and protect people from the harmful effects of oscillations. The article highlights some of the main ways to damp oscillations of rigid bus structures. Is given a mathematical model of the simplest single-mass spring inertial dynamic oscillation damper. Experimental studies have been carried out on the joint work of the rigid bus structure with the spring damper. Has been confirmed the effectiveness of spring dampers using, both outside and inside the tube-bus.

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