Mathematical Model for Proving the Compliance of Unit Attachment Assemblies of Critical Elements of Airframe Design with the Requirements of Airworthiness Standards

Abstract

All modern civil aircraft of the transport category must be certified according to the requirements of the certification basis. In Russian Federation, these are airworthiness standards, paragraph 25. This paragraph of the airworthiness standards contains a requirement for safe destruction of the structure in the event of an emergency landing and partial destruction of the landing gear. The aircraft design's compliance with this requirement must be demonstrated either experimentally or using numerical simulations. This article considers an algorithm for designing the structure of the main landing gear suspension units containing special elements in their design, "weak links", the purpose of which is destruction upon reaching certain loads. This algorithm is proposed in order to take into account the requirements of airworthiness standards for static, fatigue and dynamic strength at the early stages of airframe design. Further, the work provides a comparative assessment of the results of finite element modeling of the destruction of the shear bolt of the ear--fork connection. The maximum value of the force in the unit was taken as the evaluation criterion. The obtained data were compared with the value of the force obtained analytically. Finite element modeling of destruction was carried out in dynamic and quasi-static settings, with and without taking into account the contact problem

Please cite this article in English as:

Titov E.I. Mathematical model for proving the compliance of unit attachment assemblies of critical elements of airframe design with the requirements of airworthiness standards. Herald of the Bauman Moscow State Technical University, Series Mechanical Engineering, 2026, no. 3 (158), pp. 38--53 (in Russ.). EDN: IBDQZX

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