Aircraft Fleet Research Articles

Arranjo Institucional Histórico: a Cooperação Aeronáutica Brasil/Suécia na Década de 2010

The Defense scenario has always provided models of international cooperation, in which political-diplomatic practices are associated with varied technological demands. The FX-2 program, to achieve a fighter aircraft fleet for the Brazilian Air Force (FAB), led to studies and completion by the Swedish Gripen NG. In this field, the work presented explores the Brazil-Sweden associative model, from the perspective of social, political and economic components, mainly. The introduction to the article reveals the purpose, while a brief contextualization follows, and then theoretical references used. The methodology explains the descriptive and bibliographic nature of the production, culminating in the findings and their discussion. In this context, the social, cultural, political and economic scenarios of Swedish society are verified, in a historical review, promoting bilateral understanding and continuity within the scope of cooperation in aeronautics. Finally, a conclusion to the article takes place.

Managing Operational Efficiency and Reducing Aircraft Downtime by Optimization of Aircraft On-Ground (AOG) Processes for Air Operator

This research aims to identify patterns and root causes of aircraft downtimes by comparing various forecasting models used in the aviation industry to prevent AOG events effectively. At its heart, this study explores innovative forecasting models using time series analysis, time series modeling and binary classification to predict spare part usage, reduce downtime, and tackle the complexities of managing inventory for diverse aircraft fleets. By analyzing both data and insights shared by aviation industry experts, the research offers a practical roadmap for enhancing supply chain efficiency and reducing Mean Time Between Failures (MTBF). The thesis emphasizes how real-time data integration and hybrid forecasting approaches can transform operations, helping airlines keep spare parts available when and where they are needed most. It also shows how precise forecasting is not just about saving costs, it is about boosting customer satisfaction and staying competitive in an ever-demanding industry. In addition to data-driven insights, this research provides actionable recommendations, such as embracing predictive maintenance strategies and streamlining logistics. These steps aim to ensure smoother operations, fewer disruptions, and more reliable service for passengers and operators alike.

Optimal Flight and Maintenance Planning of a Military Aircraft Fleet through to Life-of-Type

Optimal Flight and Maintenance Planning of a Military Aircraft Fleet through to Life-of-Type

Performance Scaling of Modular Hybrid Propulsion System for Flight Vehicles

A modular hybrid propulsion system (MHPS) concept for which the electrical components are interchangeable on a mission-to-mission basis is proposed as an enabler for aircraft performance flexibility. Modular hybrid aircraft takeoff, climb, cruise, and payload performances are characterized to be functionally dependent on hybridization and modularity ratios. Scaling relationships in terms of nondimensional groups that reflect system design and operating parameters yield the following findings: For a parallel hybrid configuration, increasing hybridization improves takeoff and payload performances when electric motor specific power is greater than carbon fuel engine specific power. For all hybrid configurations, increasing hybridization decreases cruise time and range if the product of the ratios of electric motor to carbon fuel engine efficiency and battery to fuel specific energy is less than 1. With current and near-future technology, hybridization is found to be primarily beneficial for aircraft utilizing reciprocating engine(s) as the main power plant. Minimum battery specific energy and power values are found to be dependent on either the energy required for climb or the power required to drive the electric motor at peak power output; an optimum battery size would be one that meets both requirements with equality. Modularity would enable a single airframe to accomplish a wide variety of missions, potentially resulting in a reduction in aircraft fleet size. The scaling relationships provide useful guidelines for the selection and sizing of MHPS components to meet mission requirements.

Landing scheduling for carrier aircraft fleet considering bolting probability and aerial refueling

Landing scheduling for carrier aircraft fleet considering bolting probability and aerial refueling

Planning maintenance tasks in airline operating companies: A mathematical programming model applied to a case study

This paper explores a mixed-integer linear programming (MILP) approach to plan the maintenance tasks in an airline. The MILP model finds feasible maintenance plans, by minimizing the costs associated with maintenance activities and costs associated with unavailability. A constructive matheuristic approach is put forward, by solving the maintenance planning problem sequentially. The model and the matheuristic is then applied to a case study from the main Portuguese airline company. The results suggest that the proposed matheuristic approach for maintenance planning in practice, as explored in the case study, finds feasible solutions in a much lower computational time. Moreover, a sensitivity analysis is conducted to assess the impact of hangar’s capacity and other input parameters in the maintenance plan. Our approach provides an effective way to support decision-making in maintenance planning for a fleet of aircraft, while complying with several operational, technical, and labour constraints.

A bi-level heuristic maintenance scheduling framework for an aircraft fleet under uncertain mission scenarios

A bi-level heuristic maintenance scheduling framework for an aircraft fleet under uncertain mission scenarios

СТРАТЕГИЧЕСКАЯ РОЛЬ МАЛОЙ АВИАЦИИ В ТРАНСПОРТНО-ЛОГИСТИЧЕСКОЙ СИСТЕМЕ СЕВЕРНОГО РЕГИОНА (НА ПРИМЕРЕ АРХАНГЕЛЬСКОЙ ОБЛАСТИ И НЕНЕЦКОГО АВТОНОМНОГО ОКРУГА)

The socio-economic development of the northern territories of Russia directly depends on the state of regional transport and logistics systems. It is important to note that small aircraft plays a special strategic role in the connectivity of the northern territories in conditions of limited transport accessibility and the absence of other year-round transport links. Using the example of such northern regions of Russia as the Arkhangelsk oblast and the Nenets autonomous okrug, the author gives a description of the work of air enterprises on local airlines, including the route network, the state of the fleet of ships, examines the financial indicators of regional air detachments, analyzes the dynamics of passenger traffic. According to the results of the SWOT analysis of the development of small aircraft in the Arkhangelsk oblast and the Nenets autonomous okrug, it was found that its weaknesses are: high costs of organizing transportation; lack of qualified personnel; limited possibility of updating the aircraft fleet due to sanctions restrictions; postponement of the production and commissioning of new domestic passenger aircraft. The problems of excessive requirements for air transportation and operation of landing sites, rising prices for fuels and lubricants and components, which leads to an increase in the costs of regional budgets, remain common for the northern regions. For the development of small aviation in the northern regions of Russia, the article proposes such solutions as: reducing the excise duty on aviation fuel for air enterprises engaged in socially significant transportation; approving charter flights within the territory of the subject at unregulated tariffs and other routes to generate additional income within the framework of an approved transport order.

Modern Development of Transport Infrastructure in Kyrgyzstan

The article is devoted to the analysis of the modern development of transport infrastructure in Kyrgyzstan. The work considers the key trends and directions of state policy in this area. The study shows that Kyrgyzstan has a stable positive dynamic in the development of various types of passenger and freight transportation. There is an increase in the volume of automobile, rail, air, and other transport services. Particular attention is paid to the implementation of large-scale infrastructure projects for the reconstruction and modernization of key highways connecting Kyrgyzstan with neighboring countries. This contributes to improving the quality and availability of transport communications, as well as the country's integration into regional and global logistics chains. In the aviation industry, measures are being taken to expand the route network of the national air carrier, improve the quality of airport services, and renew the aircraft fleet. Comprehensive measures in the field of transport infrastructure carried out in Kyrgyzstan are aimed at increasing the efficiency, competitiveness, and environmental friendliness of the national transport system, which plays a key role in ensuring economic growth and sustainable development of the country.

РОЗРОБКА ТА ВИРОБНИЦТВО ЛЕГКИХ ЛІТАЛЬНИХ АПАРАТІВ СІЛЬСЬКОГОСПОДАРСЬКОГО ПРИЗНАЧЕННЯ

Issues of protecting plants from diseases and pests are becoming more and more urgent. Climate change causes an increase in the activity of weedy plants and insects harmful to agriculture. Because of this, the chemical treatment of fields by aviation in modern agriculture should serve the purpose of preserving the future harvest in both a qualitative and quantitative sense. An important role in this is played by the biological method of plant protection, which is quite effective and environmentally friendly. It is based on the use of living organisms, their waste products and biologically active substances that regulate the development and reproduction of harmful plant organisms. Scientists have developed technologies for the breeding of such zoophages to protect plants from plant pests: Trichogramma, predatory mite Phytoseiulus, encarzia, Aphidimyza gallica, etc., as well as the production of microbiological preparations to protect plants from diseases and pests, the high efficiency of their use has been proven. Aircraft (planes, helicopters, ultralight aircraft) that are registered in the State Register of Civil Aviation Aircraft of Ukraine and have a certificate for the right to perform aerochemical work are allowed to carry out aerial work on the application of pesticides during agrochemical activities on agricultural and forest crops. The requirements for the characteristics of the aircraft, directive requirements for the technology of production, operation and maintenance of airworthiness were formulated. The evaluation of the manufacturability of the considered products (agricultural LA) cannot be evaluated without taking into account the operational manufacturability, which largely determines the costs when performing work in the field. Along with the requirements for the manufacturability of the aircraft design, the so-called operational requirements are of great importance. These requirements determine the suitability of the structure and equipment for its maintenance and repair during the operation of the aircraft, taking into account the high quality of work, the least consumption of time, labor and materials. Satisfying operational requirements ensures reliability, durability of the aircraft, high labor productivity during maintenance, reduction of operational costs and efficiency of use of the aircraft fleet. The appearance of the trichogram required the development of special means for its introduction. An attempt to use existing means showed their unsuitability due to their low functional efficiency and high cost of work. The task was solved by increasing the manufacturability of agricultural aircraft during their production and operation. This made it possible to organize its serial production and operation in many farms of the country.

A contribution to mitigate NOx and H2O emissions for a hydrogen-powered hypersonic vehicle

AbstractHypersonic transport fueled with liquid hydrogen (LH2-HST) is currently considered as long-term future technology of civil aviation to fly with speeds greater than Mach 5 at stratospheric altitudes of 25–38 km. In this paper, we present a comprehensive methodology to assess the emission mitigation potential (via NOx and H2O) of future LH2-HST through operational measures, considering realistic constraints such as the sonic boom carpet as well as tolerable g-forces acting on the passengers while flying with hypersonic speeds. Both NOx- and H2O-optimal 4D-trajectories are identified by a brute-force algorithm that varies the initial cruise altitude from 30 to 36 km. As case study, the Mach 8 passenger aircraft STRATOFLY-MR3, which was conceptually developed in the framework of the H2020 STRATOFLY project, is operated on a single route from Brussels (BRU) to Sydney (MYA). The findings are highlighted as relative changes regarding MR3's design flight altitude set at 32 km, respectively, 105 000 ft. As scientific contribution, 3D emission inventories are calculated and made publicly available for a world fleet of MR3 aircraft operated along the BRU-MYA route on both NOx- and H2O-optimal mission profiles in the year 2075.

Integration of Foundation Models and Federated Learning in AIoT-Based Aircraft Health Monitoring Systems

The study presents a comprehensive framework for integrating foundation models (FMs), federated learning (FL), and Artificial Intelligence of Things (AIoT) technologies to enhance aircraft health monitoring systems (AHMSs). The proposed architecture uses the strengths of both centralized and decentralized learning approaches, combining the broad knowledge capture of foundation models with the privacy-preserving and adaptive nature of federated learning. Through extensive simulations on a representative aircraft fleet, the integrated FM + FL approach demonstrated consistently superior performance compared to standalone implementations across multiple key metrics, including prediction accuracy, model size efficiency, and convergence speed. The framework establishes a robust digital twin ecosystem for real-time monitoring, predictive maintenance, and fleet-wide optimization. Comparative analysis reveals significant improvements in anomaly detection capabilities and reduced false alarm rates compared to traditional methods. The study conducts a systematic evaluation of the benefits and limitations of FM, FL, and integrated approaches in AHMS, examining their implications for system robustness, scalability, and security. Statistical analysis confirms that the integrated approach substantially enhances precision and recall in identifying potential failures while optimizing computational resources and training time. This paper outlines a detailed aviation ecosystem architecture integrating these advanced AI technologies across centralized processing, client, and communication domains. Future research directions are identified, focusing on improving model efficiency, ensuring generalization across diverse operational conditions, and addressing regulatory and ethical considerations.

An approximate dynamic programming approach for solving aircraft fleet engine maintenance problem: Methodology and a case study

An approximate dynamic programming approach for solving aircraft fleet engine maintenance problem: Methodology and a case study

The future of airport noise: a comprehensive analysis of population exposure at Dublin airport 2023 to 2030

There are conflicting trends in the impact of aircraft noise as increased air traffic is offset by advancements in low noise aircraft technology. This paper considers the case of Dublin Airport and projects the noise impact of operations over the timeline to 2030. The airport projects an (Average Annual Growth Rate) of 1.2 %, translating to an estimated rise in annual air traffic movements from over 212736 flights in 2023 to around 244635 flights in 2030. This estimated increase poses not only logistical challenges for airports but also an escalation in noise pollution in the surrounding areas. The most significant challenge in predicting future airport noise exposure lies in the shifts in aircraft fleet distribution and the adoption of technology in newer generations of aircraft. This paper evaluates the most likely combination of fleet distribution and technology uptake. In 2023, the noise footprint is projected to affect a population of approximately 105762 people with Lden ≥ 55 dB. By 2030, this exposure increases to 168267 people. The increase in air traffic numbers also leads to a notable increase in nighttime flights, bringing nighttime noise exposure Ln ≥ 50 dB from 127720 in 2023 to 189376 in 2030.

Risk assessment of continued airworthiness event of transport aircraft rudder pedal strut damage

Abstract To ensure the safe operation of aircraft after delivery, a set of continued airworthiness risk assessment processes and methods for transport aircraft is studied and proposed, including unsafe condition identification, consequence severity determination, occurrence possibility assessment, risk level determination, and reaction time calculation. The continued airworthiness risk matrix is established. Based on the established process and method, the risk assessment is carried out for the continued airworthiness event of transport aircraft rudder pedal strut damage. The relationship between the risk level of the fleet aircraft and the flight duration is determined, and the reaction time of the unsafe condition of the aircraft in each flight duration is calculated. The results show that the process and method are feasible.

Aircraft Skin Machine Learning-Based Defect Detection and Size Estimation in Visual Inspections

Aircraft maintenance is a complex process that requires a highly trained, qualified, and experienced team. The most frequent task in this process is the visual inspection of the airframe structure and engine for surface and sub-surface cracks, impact damage, corrosion, and other irregularities. Automated defect detection is a valuable tool for maintenance engineers to ensure safety and condition monitoring. The proposed approach is to process the captured feedback using various deep learning architectures to achieve the highest performance defect detections. Additionally, an algorithm is proposed to estimate the size of the detected defect. The team collaborated with TUI’s Airline Maintenance Team at Luton Airport, allowing us to fly a drone inside the hangar and use handheld cameras to collect representative data from their aircraft fleet. After a comprehensive dataset was constructed, multiple deep-learning architectures were developed and evaluated. The models were optimized for detecting various aircraft skin defects, with a focus on the challenging task of dent detection. The size estimation approach was evaluated in both controlled laboratory conditions and real-world hangar environments, providing insights into practical implementation challenges.

Comparative Legal Analysis of Maritime Technology Utilization in Indonesia and China

Managing maritime borders is a vital issue that needs special attention from coastal nations such as Indonesia and China. Both designed and deployed various systems to monitor marine activity as declared in UNCLOS 1982. The goal of this study is to give a comparison of marine surveillance technologies and to analyze the legality of their usage under international law. The research methods include literature review and analysis of material from official sources, scientific publications, and relevant reports. This study discovered that Indonesia has created an integrated maritime surveillance system based on satellite, radar, and Automatic Identification System (AIS) technologies. Besides that, China is deploying more advanced and extensive maritime surveillance and monitoring technologies, such as a modern fleet of patrol vessels, aircraft, and remote monitoring equipment. Indonesia and China have generally employed marine surveillance technologies in compliance with international law principles such as territorial sovereignty, freedom of navigation, and maritime law enforcement. However, there are indications of limits on access to information and potential privacy concerns that should primarily concern the Chinese. Stronger regional coordination and collaboration are required to guarantee that the deployment of marine surveillance technologies complies with international law and current maritime security concepts.

First Results of Airborne GNSS Radio Occultation Sounding From Airbus Commercial Aircraft

AbstractThe lack of high vertical resolution atmospheric thermodynamic structure observations inside or near major weather events impedes our understanding of physical processes and their predictability in numerical weather prediction (NWP) models. Airborne Global Navigation Satellite System (GNSS) radio occultation (airborne radio occultation [ARO]) has proven to be a viable remote sensing option to offer dense soundings near flight tracks. The global fleet of commercial aircraft already equipped with GNSS receivers could be leveraged to produce an unprecedented number of ARO soundings along global flight paths. Eleven cases of atmospheric bending angle and refractivity profiles were successfully retrieved and compared with the colocated European Center for Medium‐Range Weather Forecasting global reanalysis data. Good quality measurements are obtained with median refractivity differences less than 1% in the middle and upper troposphere, between 5.5 and 11.5 km. Given the use of aircraft data (e.g., Aircraft Meteorological DAta Relay) for data assimilation, incorporating ARO profiles would be a valuable addition, further enhancing the accuracy of aviation and weather forecasts.

Predicting airport noise impact to 2040: Traffic growth and technology uptake

While the volume of air traffic continues to rise, there are concurrent shifts in aircraft fleets and advancements in technology aimed at enhancing aircraft efficiency, sustainability, and minimizing noise footprints. These simultaneous developments contribute to the complexity of forecasting airport noise associated with future air traffic. This study presents various scenarios of technology adoption for the years 2030 and 2040 at a European airport, namely Dublin Airport, encompassing changes in fleet distribution. Aircraft are classified into different generations to reflect their technological advancements. Projections indicate an anticipated growth in the wide body fleet at Dublin Airport from 2023 to 2040, while the shares of narrow body, regional jet, and turboprop fleets are expected to decline. Each forecast year showcases three distinct technology uptake scenarios, with noise contour lines at Lden = ▪(A) and Lnight = ▪(A) being compared. To assess the impact of these changes on airport noise, the study evaluates alterations in area and population exposure. In general, the findings suggest a trend of increasing population exposure coinciding with the rise in air traffic. Nevertheless, the increase of wide body aircraft at Dublin Airport further increases the noise impact in 2030. Anticipated growth sees new generation 2 aircraft reaching up to ▪ by 2040, leading to a reduction in 2040 noise contour lines compared to 2030—though not returning to the levels observed in 2023.

Electric Taxiing System. Kinetic Energy Recovery System as an Electric Taxiing Solution: Economic and environmental analysis: Phenom 300 case study

Electric Taxiing System. Kinetic Energy Recovery System as an Electric Taxiing Solution: Economic and environmental analysis: Phenom 300 case study