The article deals with the issues of ensuring the operational survivability of the airframe design of the aircraft during the design and operation stages. The distribution of incidents by types and sources of accidental damage is presented. The statistical data obtained as a result of the analysis of incidents related to structural damage characterizing the degree of a damaging factor danger are given. The analysis of factors affecting the structure safety is given. An approach to operational survivability schemes formation is discussed.

The paper considers a complex criterion for assessing the characteristics of the radio-transparent fairing of the supersonic aircraft onboard radar. The algorithm for research performing which will allow to establish interrelation between radio, aerodynamic and the main geometrical characteristics of radio-transparent nose fairings, such as lengthening of the forward part of a fuselage, an angle of inclination of a tangent to a curve forming a body of rotation and a discriminant of a curve generator is developed. The process of forming the geometric shape of the onboard radar radio-transparent fairing of a supersonic aircraft is based on two interrelated processes: providing the appropriate radio technical characteristics of the fairing to meet the requirements for the range of the aircraft radar detection and minimizing the drag of the nose of the fuselage. Research following the proposed algorithm allows forming technical recommendations for the selecting rational geometric parameters of onboard radar radio-transparent fairing of a supersonic aircraft at the early stages of aircraft design.

The paper presents an overview of the main strength requirements to the typical civil aircraft landing gear design. Elements of the main landing gear leg mount on the airframe were considered in more detail. In the mount points, shear bolts called the ”weak links” are usually installed in order to prevent transferring the dangerous loads during rough landing to the critical airframe sections. Next, calculations of the typical “weak link” effecting the shear were compared by two methods. Analytical static calculation showed the shear force value being lower than the dynamic calculation by the finite element method, which indicates the need for additional research to identify true value of the shear force in the weak link section during the aircraft rough landing.

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The paper emphasizes the relevance of the problem of resonance in aircraft airframe structural elements, and relying on the operating experience shows the consequences of this phenomenon in terms of fatigue cracks occurring in the details of the aircraft airframe during vibration load. The types and consequences of failures in aviation equipment airframe structural elements arising from vibration load are analyzed. On the example of the slat, the forms of natural oscillations of high-lift devices are investigated, their relationship with the rotational frequencies of the high and low pressure rotors of the lift-propulsion system is shown. The study introduces the method of frequency offset of the structural pattern of the object under consideration, and implements the algorithm for modal analysis of a metal structure on the basis of modern applied packages of three-dimensional modeling and engineering analysis. The place of analytical calculations in the structure of the entire product life cycle is noted.