Aircraft Manufacturing Research Articles

Stacking Effect of Carbon/Glass Fiber During Drilling Operation of Laminated Polymer Composite

Nowadays, fiber stacks are extensively used in the aircraft and structural component manufacturing industries. It is mainly due to their excellent mechanical and physiochemical performances. The different stacking sequences of fiber materials expand the structural properties due to high-strength carbon fiber and low-cost glass fiber. The fragile and anisotropic conduct of Carbon (Cf) and Glass (Gf) laminates generates different types of complex machining issues. This article focuses on the Drilling test of Carbon/glass fiber hybrid composites using different stacking sequences. The effect of varying stacking orders is explored in this study to identify a feasible composite. The control of varying constraints, namely, spindle speed (N), feed rate (f ), and stacking sequence (SS) of carbon (Cf) and glass fiber (Gf) reinforcement, is performed to achieve the optimal parametric condition. The finding reveals that sample A (C4G4) stacking sequence provides an acceptable value for thrust force 59.05 N and delamination 1.0001 for high drilling efficiency. The stacking technique of carbon/glass layers can be endorsed to the manufacturing sector for cost-effective composite development and a defect-free machining environment.

Psychological research in vibration disease: level of alexithymia, psychological defenses

Vibration disease ranks among the first in the structure of diseases in workers at mechanical engineering enterprises, metallurgical, mining, and construction industries, various branches of agriculture, and aircraft manufacturing. A change in the mental status of people working in vibration conditions was identified; the most common are «neurosislike states» with psycho-emotional disorders of anxiety type. Meanwhile, currently existing data on the state of the nervous system in vibration pathology are contradictory and scarce, which requires a more in-depth study. Purpose of the study: to investigate the psychological status of patients with vibration disease from the action of both local and general vibration. Research results. In patients with vibration disease from the action of both local and general vibration, a predominance of destructive psychological defenses (projection and repression) over constructive ones (compensation and rationalization) is observed.

Advanced nanocomposite coating for aluminium alloy with enhanced corrosion resistance, flame retardancy, and mechanical strength in aircraft manufacturing industries

Nanocomposites incorporating impermeable two-dimensional materials offer promising solutions for safeguarding metals against corrosion. Here, we explore the integration of [3-(2-aminoethylamino)butyl]triethoxysilane (ABES) functionalized tantalum nitride (Ta3N5) into a coating matrix, leveraging Ta3N5's exceptional chemical and thermal stability to enhance the barrier effect. When combined with graphitic carbon nitride (GCN) within polyurethane (PU), functionalized Ta3N5 contributes to enhanced corrosion resistance and fire-retardant capabilities. Evaluation of aluminium's protective behavior in chloride environments using electrochemical methods reveals significant improvements with varying amounts of functionalized Ta3N5/GCN in PU coatings. The resulting PU composite exhibits superior flame retardation, evidenced by substantial reductions in peak heat release rate (pHRR), total heat release (THR), and total smoke production (TSP) compared to pure PU. Electrochemical impedance spectroscopy (EIS) measurements demonstrate enhanced coating resistance (8.75×10¹¹ Ω.cm²) for PU/functionalized Ta3N5/GCN, even after 45 days of exposure to the electrolyte. Additionally, the newly formulated PU/functionalized Ta3N5/GCN coating exhibits exceptional water repellency, boasting a water contact angle (WCA) of 165°. Regarding mechanical properties, PU/functionalized Ta3N5/GCN displays favorable adhesion strength and hardness within the PU substrate, ensuring sustained integrity even under prolonged immersion. Consequently, this nanocomposite holds promise as a valuable coating component in aerospace applications. Therefore, the integration of functionalized Ta3N5/GCN within the PU matrix represents a novel approach to developing multifunctional coatings with improved performance across various metrics essential for aerospace materials. This work contributes significantly to advancing the field by offering novel solutions for corrosion protection and fire resistance, setting a new standard for the development of advanced coatings in aerospace and beyond.

An Agile Adaptive Biased-Randomized Discrete-Event Heuristic for the Resource-Constrained Project Scheduling Problem

In industries such as aircraft or train manufacturing, large-scale manufacturing companies often manage several complex projects. Each of these projects includes multiple tasks that share a set of limited resources. Typically, these tasks are also subject to time dependencies among them. One frequent goal in these scenarios is to minimize the makespan, or total time required to complete all the tasks within the entire project. Decisions revolve around scheduling these tasks, determining the sequence in which they are processed, and allocating shared resources to optimize efficiency while respecting the time dependencies among tasks. This problem is known in the scientific literature as the Resource-Constrained Project Scheduling Problem (RCPSP). Being an NP-hard problem with time dependencies and resource constraints, several optimization algorithms have already been proposed to tackle the RCPSP. In this paper, a novel discrete-event heuristic is introduced and later extended into an agile biased-randomized algorithm complemented with an adaptive capability to tune the parameters of the algorithm. The results underscore the effectiveness of the algorithm in finding competitive solutions for this problem within short computing times.

Real-time modeling of the riveting process forces for aircraft panel structures

The riveting of large panels in aircraft manufacturing requires an automatic drilling and riveting machine capable of precise and stable operation. However, the significant nonlinearity and time-varying nature of riveting process forces severely impact the control capacity and operational accuracy of these machines. So, the objective is to provide technical assurance for the precise operation of the machine and ensure high-quality riveting of the panels. Therefore, a real-time modeling method for the automatic riveting process forces on aircraft panels is proposed, which focuses on the rivet die's downward compression displacement as the core variable and accounts for the non-uniform deformation of rivets. This method assumes a constant volume for the rivet rod. It combines power-law hardening and Coulomb's friction theories to establish three sub-models for different riveting stages: the elastic stage, the plastic deformation stage, and the driven head formation stage. Further, considering the continuity of rivet's deformation, rivet rod's cross-section stress, and the driven head dimensions changes with the driven head's downward compression displacement, a novel real-time continuous dynamic load model for the full compression riveting process of a single-rivet is developed. The results indicate that the model is effective, with a maximum deviation of 7.50 % between experimental and predicted values, demonstrating its accuracy and reliability. In conclusion, this research provides a real-time, continuous description of the riveting process force, enabling automatic machines to promptly detect defects and deformations in the riveting.

An improved genetic algorithm based on reinforcement learning for aircraft assembly scheduling problem

The assembly work of aircraft occupies a significant portion of the time in aircraft manufacturing. The aircraft assembly operations are highly challenging in the generation of production plans due to multiple constraints in the scheduling process. In addressing the aircraft assembly scheduling problem with the objective of minimizing the duration of assembly operations, a mathematical model has been established. This model incorporates characteristics such as job sequencing constraints, resource constraints, spatial constraints, and others, the problem-solving process is divided into two stages: determining the priority sequence of tasks and establishing the start times for each task. Proposing an improved genetic algorithm based on Q-learning, referred to as QIGA (Q-learning-based Improved Genetic Algorithm), utilizing Q-learning to dynamically adjust the crossover and mutation probability parameters during each iteration to enhance the algorithm’s convergence speed and search capabilities. Constructing a Markov Decision Process (MDP) model to dynamically adjust the crossover and mutation probability in the problem, proposing a state set partition rule based on the population’s fitness values, setting the action set to represent crossover and mutation probabilities in different intervals. Additionally, designing reward rules based on the population’s performance. Finally, the effectiveness of the proposed algorithm is verified with a real case containing 44 assembly operations, and the results show that the algorithm can solve the aircraft assembly scheduling problem well. Validating the feasibility and optimization effectiveness of the algorithm through various aircraft assembly scheduling cases of different scales. The experimental results indicate that, compared to traditional meta-heuristic algorithms, the proposed algorithm demonstrates superior optimization performance in aircraft assembly scheduling problems. It effectively reduces the total duration of aircraft assembly operations.

Few-shot anomaly detection with adaptive feature transformation and descriptor construction

Anomaly Detection (AD) has been extensively adopted in industrial settings to facilitate quality control of products. It is critical to industrial production, especially to areas such as aircraft manufacturing, which require strict part qualification rates. Although being more efficient and practical, few-shot AD has not been well explored. The existing AD methods only extract features in a single frequency while defects exist in multiple frequency domains. Moreover, current methods have not fully leveraged the few-shot support samples to extract input-related normal patterns. To address these issues, we propose an industrial few-shot AD method, Feature Extender for Anomaly Detection (FEAD), which extracts normal patterns in multiple frequency domains from few-shot samples under the guidance of the input sample. Firstly, to achieve better coverage of normal patterns in the input sample, we introduce a Sample-Conditioned Transformation Module (SCTM), which transforms support features under the guidance of the input sample to obtain extra normal patterns. Secondly, to effectively distinguish and localize anomaly patterns in multiple frequency domains, we devise an Adaptive Descriptor Construction Module (ADCM) to build and select pattern descriptors in a series of frequencies adaptively. Finally, an auxiliary task for SCTM is designed to ensure the diversity of transformations and include more normal patterns into support features. Extensive experiments on two widely used industrial AD datasets (MVTec-AD and VisA) demonstrate the effectiveness of the proposed FEAD.

Computational Analysis of Magneto Bioconcvection Casson Nanofluid Flow Containing Gyrotactic Microbes: A Bio-Microsystemtechnology and Bio-Fuel Cells Application

Scientists and researchers have been captivated by the field of nanotechnology research, drawn to its diverse applications such as cancer treatment, pharmaceuticals, aircraft manufacturing, nano-robot technology, bionano advancements, heat exchange instruments, engine coolant use, microelectronics, water distillation, pharmaceutical procedures, and rubber materials. Incorporating gyrotactic microbes into nanoparticles is crucial for enhancing the thermal efficiency of various systems, including microbial fuel cells, bacteria-powered micro-mixers, micro-volumes such as microfluidic devices, enzyme biosensors, and chip-shaped microdevices like bio-microsystems.This study focuses on investigating the bioconvectional flow of Casson nanofluid, incorporating nano-particles, gyrotactic micro-organisms, and thermal radiation, passing through a needle. The bioconvection fluid is formed through the combined effects of Lorentz forces, a magnetic field, and the interaction of motile micro-organisms with nanoparticles. The governing partial differential equations are transformed into ordinary differential equations using resemblance transformations, and the solution is obtained through the BVP4C solver shooting technique. The numerical results are presented using MATLAB, depicted in figures and tabular formats. The findings, interpreted from a physical standpoint, reveal that fluid flow decreases with an increase in bioconvection Rayleigh number and buoyancy ratio parameter. Thermal flow, on the other hand, increases with a rise in Brownian motion parameter and thermophoresis effect parameter. Concentration profiles decrease with an increase in thermophoresis parameter and Lewis number, while motile microorganism profiles decline with an augmentation in Peclet number and bioconvection Lewis number.

Sustainable Airport Management and Airline Marketing

The aviation sector comprises every industry that provides direct assistance to mechanical air transportation. The aviation industry includes a variety of institutions, such as military aviation companies, aircraft manufacturers, and various commercial establishments, all of which play important roles. The analysis of airline market shares was carried out within the realm of the aviation industry. Considering the ongoing trajectory of increasing airline market shares, it is crucial for firms to commit resources towards investing in this industry. Furthermore, a thorough evaluation of the existing literature revealed a dearth of research specifically focused on airline marketing. The primary objective of this research was to address the existing gap in the literature. Sustainable airport management and business, the airline industry, business-to-business analytics in the airline sector, customer satisfaction, and customer experience were some of the facets investigated in this study. In addition, the study seeks to provide a SWOT analysis of the airline marketing strategies employed by transportation corporations.

Application of carbon fiber composite materials in aircraft

Carbon fiber composite is a material with excellent mechanical properties. Compared with other high-performance fiber materials, carbon fiber composites have the advantages of high strength and high modulus even at ultra-high temperatures. In addition, the carbon fiber composite material also has excellent electrical and thermal conductivity and electromagnetic shielding performance. Carbon fiber composites are widely used in the aircraft manufacturing industry due to their incomparable performance with other composite materials. In recent years, the amount of carbon fiber composite materials in newly developed aircraft products has reached more than 50%. This paper aims to explore the application of carbon fiber in aircraft, and to reflect the importance of carbon fiber composite materials by comparing models that use composite materials and models that do not use composite materials. The study explores the application of carbon fiber composite materials in aircraft through a comprehensive literature analysis and review. Key findings indicate significant advantages of these materials in enhancing aircraft performance, including reduced weight and increased strength. The paper also discusses the challenges in manufacturing and environmental impacts, offering insights into future research directions for sustainable aviation technologies.

Experimental Study and Analysis of Aerodynamic Characteristics of Gliders with Different Wing Geometries

At present, airplanes are widely used in people's daily lives, and research on this means of transportation is of great importance. Currently, academic research still lacks the influence of different aircraft wing shapes and areas on aircraft flight conditions. This article analyzes the basic principles of glider flight and explores the aerodynamic principles of gliders through paper plane simulation. Firstly, this paper introduces the development history of gliders. Secondly, the mechanical analysis of the aircraft is carried out. The factors that affect the flight performance of the aircraft are analyzed by paper airplane simulation experiments. The experimental results are analyzed, and the future development direction is forecasted. From the final research results, there is a close relationship between the aspect ratio and the glide angle of the plane. In the experiment, lower induced drag allows the aircraft to move further horizontally while descending resulting in a smaller glide angle. This study reveals the relationship between aspect ratio and glide angle, which provides intellectual support for the development of the aircraft manufacturing industry.

Evaluation Approach for Residual Stress in Drilling of Aluminum Alloy

Residual stress is one of the critical evaluation factors as well as machining accuracy and surface finish in cutting. From the perspective of the fastening strength of parts, residual stress in drilling has an influence on the product or part life. Especially in the aircraft manufacturing, the tensile residual stress is crucial as it can cause major accidents. However, few studies have focused on residual stress in drilling so far. Most of them investigated the characteristics of residual stress based on the experimental data. This paper discusses residual stress in drilling in terms of its mechanical effect. The residual stresses in the inner surfaces of holes were measured in the depth direction from the top of the plate. The change in the residual stress has good correlation with the chip flow direction and the load applied to the inner surface, which acts as a counter force to the cutting force near the outermost ends of the lips. The cutting force is determined using an analytical model based on the minimum cutting energy. The correlation between the residual stress and the direction of the load applied to the inner surface depends on the margin width and back taper on the peripheral sides of a drill. The effect of the margin contact on the residual stress is characterized by linear regression analysis. Finally, an analysis-neural network hybrid system was developed to estimate the residual stresses in drilling. In the system, the mechanical effects of the drilling process, which are the magnitude and direction of the load applied to the inner surface, are obtained through analytical simulation. Meanwhile, the margin effects are expressed as the coefficients in the linear functions, which are associated with the margin width and back taper angle by a neural network. Then, another neural network, working as a post process, estimates the residual stresses using the information of mechanical and margin effects. The developed system is validated by presenting a comparison between the estimated and the actual residual stresses.

Special Issue on Advanced Metal Cutting Technologies

Cutting technologies are utilized in many industrial sectors, such as automobile, aircraft, and medical-device manufacturing as well as dies and molds. Thus, the requirements for higher geometric accuracy, better surface integrity, and longer component service lifetimes have substantially increased. In addition, maintaining high machining efficiency while simultaneously reducing power consumption and CO2 emissions during machining is important for sustainable development. This special issue features 11 papers on the most recent advances in cutting technologies for metals and composite materials. - Reverse finishing characteristics of drilling surfaces - Machining error simulation for end milling - Visualization of cutting phenomena using a single-crystal diamond tool - Milling of TiB2 particle-reinforced high-modulus steel - Electrodischarge-assisted turning of carbon fiber-reinforced polymers - Suppression of chatter vibration during double-insert turning - Prediction of surface roughness components during turning - Microtome blades for high-precision tissue sectioning - Boiling of coolant near the cutting edge in high-speed machining - Residual stress during drilling of aluminum alloy - Effect of strain hardening on burr control during drilling This issue provides an understanding of recent developments in cutting technologies, aiming to inspire further research in this field. We deeply appreciate the careful work of all the authors and thank the reviewers for their diligent efforts.

Exploratory Study of Sustainability Practices in Worldwide Major Aircraft Maintenance, Repair, and Overhaul Companies

While sustainable aviation research has primarily focused on the airline industry, aircraft manufacturing, and airport responsibilities, the aircraft maintenance, repair, and overhaul (MRO) industry’s contribution to achieving sustainable aviation goals has been overlooked. This study examines the approaches to corporate sustainability practices used by aircraft MRO companies worldwide. The methodology used to investigate the sustainability actions of major MRO companies globally was mainly based on observational data gathered from multiple data sources, such as environmental, social, and governance (ESG) and investor relations documents. Four companies out of the 13 major MRO companies whose sustainability reports were found are examined as a case study analysis. Each MRO company adopted different definitions and practices of sustainability. The findings show that the aircraft MRO sustainability definition varies among the major companies studied, but some commonalities can be used to develop a proposed definition. The authors propose that aircraft MRO sustainability be defined as the ability to conduct MRO business that positively affects all stakeholders while emphasizing safety, quality, and integrity values, using technology and innovation to make growth, and constantly stabilizing and/or diminishing the impact on the environment. This study contributes to the understanding of sustainable aviation by highlighting the role of MRO companies in achieving sustainable goals.

Current issues of industrial and technological cooperation in the EAEU countries

The subject of the study is the integration of production processes and technology exchange between Russia and the EAEU countries. The purpose of the work is to analyse the organizational and economic mechanisms of industrial and technological cooperation in the EAEU countries and to determine the conditions for increasing their effectiveness in the context of sanctions policy aimed at restricting the access of the Russian economy to foreign markets. The methodological basis of the research is a systematic approach, methods of induction, deduction, analysis and synthesis. The article considers examples of successful activities of joint ventures – one of the leading forms of industrial and technological cooperation between Russia and the EAEU countries, common in the automotive industry, aircraft manufacturing, energy and petrochemistry. Their creation stimulates economic growth, promotes industrial diversification and strengthens the international positioning of the region. The analysis revealed the following positive results from the organization of joint ventures between Russia and the EAEU countries: expansion of markets and increased production volumes, technology exchange and high innovation potential, employment generation and competence development. The problems that reduce the positive effect were also identified, in particular, the lack of harmonized standards, financial risks, managerial and cultural differences. Solving these problems requires combining the efforts of business and government agencies. The results of the study demonstrate the importance of creating and improving the efficiency of joint ventures in the EAEU countries, they can be used to adapt Russia’s economic strategy to new geopolitical conditions.

Circular Economy: A Technological Innovation Strategy for Sustainability in Air Transport

This work aims to identify innovations, technological advances, and best practices to migrate towards a circular economy in air transport. The relevance of the research lies in the contribution to the generation of circular economy knowledge in the field of administration with application in the aeronautical industry. By analyzing literature and best practices, the circular economy could be a viable solution to reduce the use of natural resources in aircraft manufacturing and airport operations. Among the main findings are innovations and technological developments in new materials, fuels, building methods, and best practices implemented at airports to obtain energy and generate less waste. It has also been identified that applying circular economy principles in this mode of transport would contribute to sustainability efforts and increase the competitiveness of organizations in the sector.

Shape Control of Elastic Deformable Linear Objects for Robotic Cable Assembly

Currently, cables are manually installed in aircraft manufacturing scenarios. The utilization of robots in cable assemblies can enhance efficiency and ensure quality, presenting great promise for the future. However, the assembly process must control the shape of the cables, which is a significant challenge for robots. On the one hand, cables have high degrees of freedom in space, making accurate modeling of cable dynamics for robotic arm manipulation difficult; on the other hand, cable deformation has uncertainty, and the applied forces cause simultaneous deformation and motion, which is difficult to control. To address these problems, this study proposes a cable‐shape control method based on graph neural networks and online visual shape‐servoing. The method first approximates cable dynamics with a graph neural network. Then, in practice, the learnt model is used alongside visual‐based shape‐servoing to generate optimal robotic arm movements, controlling the cable to attain the desired shape. In the experiments, precise control of three different cable types is realized, and an example of a completed cable assembly is shown.

Features of immunopathogenesis, prognosis and quality of life in vibration disease and its combination with bone and joint disorders

The article describes the features of working conditions, the clinical picture, the state of the immune profile, cytokine regulation in vibration disease from the effects of local vibration with its combined forms with deforming osteoarthritis in the assembly riveters of an aircraft manufacturing enterprise. Objective: to identify the clinical and pathogenetic features and quality of life in vibration disease from the effects of local vibration with its combined forms with deforming osteoarthritis. The level of C-reactive protein and rheumatoid factor was studied by the solid-phase enzyme immunoassay (ELISA). Immune disorders in vibration disease and its combined course with ostearthritis were investigated by methods including the determination of CD4+, CD8+ lymphocyte subpopulations. To assess the cytokine status, the content of interleukins 1‑beta (IL-1β), 4 (IL-4), 8 (IL-8) in blood serum was analyzed. The study of the quality of life was conducted using the SF-36 questionnaire. The calculation of the statistical significance of the differences was carried out according to the Mann-Whitney criterion. The prognostic value of changes in the immune profile and cytokine regulation in vibration disease from the effects of local vibration with its combined forms with deforming osteoarthritis has been established. In case of vibration disease from the action of local vibration and its combination with deforming osteoarthritis, clinical and pathogenetic changes are characterized by a significant decrease in the levels of CD4+, CD8+ lymphocyte subpopulations, an increase in serum concentrations of IL-1β, IL-8. Taking into account the fact that the development and manifestation of symptoms of vibration disease from exposure to local vibration, including comorbid conditions (which include deforming osteoarthritis) manifests itself later than changes in the immune status are recorded, the creation of dynamic monitoring of the health status of persons in contact with industrial vibration is of great practical importance. The prognostic value of determining the quality of life in vibration disease from the effects of local vibration and its combined forms with deforming osteoarthritis has also been established.

Time-triggered scheduling of mixed-critical flows at end-system in asynchronous AFDX avionic network

Avionics Full-DupleX (AFDX) is a switched Ethernet-based network used in modern commercial airplanes for the transmission of command and control avionics flows. These critical flows require deterministic guarantees leading to a lightly loaded network. Aircraft manufacturers envision to carry additional non avionics flows (i.e. video, audio, service) to take advantage of the spare bandwidth. However, it is then compulsory to preserve the real-time guarantees of avionics flows in terms of bounded jitter at the transmitter output and of bounded end-to-end latency. Depending on the type of additional traffic, Quality of Service (QoS) end-to-end guarantees may be offered to the additional flows of lower criticality in terms of reduced delay or bounded jitter for instance. These guarantees can be ensured by scheduling policies at transmitter and switch level. However, an important safety-related constraint is the asynchronous design of avionics distributed systems that prohibits the use of a network-wide synchronization of end systems and switches. Thus, time-triggered networking such as emerging Time-Triggered Ethernet (TTEthernet) or Time-Sensitive Networking (TSN) cannot be leveraged. This paper underlines the benefits of only scheduling flows at the transmitter, which is compatible with the asynchronous safety constraint of avionics systems. We show that it is possible to build a table schedule that carries both critical avionics flows and additional video flows that meet their timing and bandwidth allocation constraints. Therefore, we design scheduling strategies for efficient distribution of flows in the table scheduling whose performance is compared to the optimal schedule minimizing the emission lag of additional flows. Proposed heuristics are constructed such as to favor the network responsiveness for avionics flows thanks to slot over-provisioning. Extensive results on an A350 AFDX industrial configuration show that for a transmitter load of up to 70% of the available bandwidth, the uniform allocation heuristic provides a performance close to optimal in terms of minimum emission lag for additional flows, so offering a practical configuration heuristic to industry.

Lnvestigation of the Effect of a Mechanical Stress Concentrator on the Processes of Occurrence and Development of Cracks in Structural Elements of Aviation Equipment

The purpose of the research is investigation of the patterns of crack development in structural elements of aviation equipment from a stress concentrator under the influence of a force stretching along the main axis, symmetrical alternating loads (vibrations) and combined effects in order to determine the criticality of operation of aircraft products with crack-type defects, substantiation or refutation of the need for research and operation of the processes of development of stress-strain states preceding the occurrence of a crack, in systems and complexes of periodic, preflight and operational control of the technical condition of aircraft products.Methods. Еxperimental study of the patterns of crack development from a stress concentrator in structural elements of two form factors: a cylindrical sample (GOSТ 25347-82) simulating a stringer or a load-bearing structural beam, and a plate sample (GOSТ 1497-84), simulating an aircraft skin element. Cylindrical samples were subjected to deformation caused by the kinetics of rotation, plate samples were subjected to uniaxial tensile stress and the effects of alternating loads (vibrations) individually and in combination.Results. Тhe patterns of near-surface and deep crack development, their relationship with the frequency of application of symmetric alternating loads, have been studied. Еxpressions are established for the approximate engineering calculation of the material endurance limit, fracture surface area and constant endurance with an approximation accuracy Proceedings of the Southwest State University. Series: Control, Computer Engineering, of about 0.8. For samples in the form of flat plates, a stress-strain diagram is constructed, clearly illustrating the decrease in the endurance of the material to the effects of combined loads in relation to the effects of static tensile stresses only. Тhe approximate number of residual cycles before the structural element is destroyed is estimated, taking into account the amplitude-frequency parameters of the acting vibration in the presence of a crack in the sample. Тhe estimation method using the load intensity coefficient and mathematical expressions for its calculation is given.Conclusion. /t is concluded that it is necessary to analyze the dynamics of the development of stress-strain states (fatigue) of the material as states preceding the appearance of cracks in order to carry out sufficient control of the technical condition of structural elements of aircraft products.