Application of Low-Speed Shock Damage to Full-Size Aircraft Parts Made of Polymer Composite Materials During the Preparation of the Object for Strength Tests When Confirming Compliance With the Requirements of Aviation Regulations

Abstract

The paper describes the results of a set of statistical data on damage as applied to various structural zones on the application of low-speed impact damage to full-size parts made of polymer composite materials of an aircraft engine to work out the statistics. For this type of work, an installation for application of the required low-velocity impact damage, similar to a pendulum- type copter, has been developed; the developed installation allows application of low-velocity impact damage in a certain range of energies. When performing the work, different zones of the structure (regular shell, flange thickenings, places of thickness change, etc.) were taken into account, the damage was applied taking into account the selected zone. Based on the results of the work, a set of statistical data of applied damage (geometric dimensions, impact interaction characteristics, visual differences) for different structural zones of the structure was obtained, statistical analysis of the obtained test results with determination of average values, standard deviations and variation coefficients of damage depth and maximum diameter was performed. The results of the work are presented in the form of plots of dependences of geometric dimensions of the damage on the actual impact energy. The presented approach to low-velocity impact damage, which is based on the use of full-size structures as test objects, makes it possible to unambiguously determine the required parameters of impact damage to be taken into account when planning the experiment and when substantiating the static and fatigue strength of the structure.