Aircraft Maintenance Activities Research Articles

Treatment of aircraft maintenance wastewater by coupling low-temperature evaporation with Fe–C micro-electrolysis-configured ozonation

ABSTRACT A novel approach combining low-temperature evaporation with Fe–C micro-electrolytic ozone oxidation has been devised for treating substantial volumes of high-concentration organic cleaning wastewater generated during aircraft maintenance activities. The findings from experiments demonstrate impressive average removal rates for various contaminants, including chemical oxygen demand (93.1%), oil concentration (94.0%), suspended solids (98.9%), turbidity (98.8%), chroma (93.8%), total nitrogen (93.7%), and total phosphorus (99.2%). Within this integrated system, the synergistic effects between ozone oxidation, catalytic fillers, and electrochemical processes significantly enhance pollutant removal efficiency. The chemical oxygen demand reduction rates of the cleaning wastewater derived from engine maintenance, mechanical and electrical maintenance, aircraft accessory maintenance, and mixed wastewater exceed 98%. The optimal reaction times for four types of wastewater are 150, 120, 90, and 120 min, respectively. The time can be adjusted according to the different treatment objects in actual operation projects. Moreover, the average concentration efficiency achieved surpasses 92% while meeting all effluent quality standards set forth by municipal sewage networks, and it has reduced the disposal cost of the enterprise by about 80%. This technology provides enterprises with an effective way to reduce energy consumption and expenses.

Beyond flight operations: Assessing the environmental impact of aircraft maintenance through life cycle assessment

As the aviation industry strives to minimise its environmental footprint, understanding the full life cycle impacts, including maintenance, becomes essential for sustainable development. This paper addresses the critical research gap in the environmental assessment of aircraft maintenance by conducting a comprehensive life cycle assessment based on an Airbus A320 aircraft. By combining a top-down check-level analysis and a detailed examination of the aircraft manufacturer’s maintenance planning document, this study provides significant insights into the environmental implications of maintenance activities. The check-level analysis provides a general overview, while the analysis of the maintenance planning document delves into individual tasks, enabling the identification of components with the highest ecological impacts. This research emphasises the importance of including aircraft maintenance activities in life cycle assessment studies and provides valuable guidance for researchers, industry practitioners, and policy makers in prioritising sustainability measures and enhancing the environmental performance of aircraft throughout their life cycle.

Failure analysis of aviation hydraulic rotary joints

The aviation hydraulic rotary joint is an accessory of the aviation hydraulic system used to connect two pipelines in relative motion. The safety accident caused by the failure of the aviation hydraulic rotary joint occurred in engineering. The analysis of the potential failure causes of aviation hydraulic rotary joints can provide basic technical support for aircraft maintenance activities. In this study, a ground reliability experimental apparatus for an aviation hydraulic rotary joint was built, and a reliability test was conducted. The potential failure mode of an aviation hydraulic rotary joint was analyzed by observing the surface topography of each component. Finally, the failure mechanism was analyzed using the finite element method. To provide a basis for the maintenance and replacement strategy of the joints, the influence of the fit clearance on the reliability of aviation hydraulic rotary joints was analyzed. The results show that the wear of metal components and sealing components and the stress failure of sealing components are the main failure mechanisms of rotary joints; when the fit clearance increases from 0.02 mm to 0.12 mm, the maximum von Mises stress and maximum shear stress of the retaining ring were increased by 44.45% and 43.72%, respectively, and the maximum von Mises stress and maximum shear stress of the O-ring were increased by 131.89% and 123.64%, respectively. With the increase of the fit clearance, the stress damage probability of the retaining ring and O-ring will increase. The maintenance and replacement strategy of rotary joints can be made according to the size of the fit clearance.

A Quantitative Study of Aircraft Maintenance Accidents in Commercial Air Transport

Aircraft maintenance is defined by the ICAO as the tasks that need to be carried out on an aircraft to ensure its continuing airworthiness. Accidents that result from aircraft maintenance activities are a direct measurable outcome that can be used to broadly assess the effectiveness of maintenance activities. This research seeks to understand the characteristics of aircraft-maintenance-related accidents and how these have changed over time. An exploratory design was utilized, which commenced with a content analysis of 358 accidents from the Aviation Safety Network, followed by a quantitative ex post facto study. The results showed that aircraft-maintenance-related accidents were 1.7 times less fatal compared to all aviation accidents in the database. Fatalities were reduced significantly from the 1990s following major accidents with many fatalities; this was countered by several industry-wide initiatives. However, the number of accidents have continued to grow by one each year. Relative to all accidents, it was found that maintenance contributes to (2.0 ± 0.4)% of all accidents, which increased to (3.8 ± 0.7)% from 1998 to 2019, up from (1.3 ± 0.2)% from 1941 to 1997. However, the rate of maintenance accidents per kilometer flown has decreased exponentially halving every 27.7 years. The results showed that the most common age of an aircraft involved in a maintenance accident was 5 to 15 years, corresponding to the first heavy maintenance period of an aircraft (6 to 12 years). Further results for age showed no correlation to the fatalness of accidents; however, older aircraft were more likely to be written off.

Maintenance 4.0: Automation of Aircraft Maintenance Operational Processes

The advancement of technology is ramping up the pace of digitization and automation of aircraft maintenance activities, and with that, the stakeholders’ interest in high-level technology has also increased over the past few years. Thus, to stay relevant in the market and capable of competing, Aircraft Maintenance and Overhaul (MRO) companies must reshape and adapt to newer methodologies to enhance and enrich the quality of aviation and after-sales services. Operational processes are essential to any successful business because it plays a vital role in the efficient and effective functioning of the organization and structure of the enterprise. Hence, this paper will focus on the possibilities of automation and data integration into the daily operational workflow, its contribution, and its influence on the industry. And since the initiation of Industry 4.0, newer opportunities and possibilities have arisen to investigate decision-making algorithms, their influence on overall job quality and precision as well as the synergy between humans and machines and their cooperation in the operational areas of the maintenance process.

PERENCANAAN MANAJEMEN PROYEK DALAM PERAWATAN APU GTCP131-9B PT. GARUDA INDONESIA

The air transportation industry in Indonesia is growing rapidly and is very competitive. Aircraft fleet maintenance is an important factor in supporting airlines to compete in the local and global industry. On the other hand, delays in the completion of fleet maintenance can result in delays in flight schedules and this is very detrimental to the airline and passengers. This is a challenge for business actors in the aircraft maintenance sector because of the risk of being penalized for delays that occur. Therefore, this study aims to reduce the risk of late fines faced by aircraft maintenance business actors. With project management, the company is expected to be able to produce effective and efficient maintenance activities. This is very much needed by the company in producing optimal output and has a great impact on airlines that use aircraft maintenance services. In this study, the evaluation of project management uses the Critical Path Method (CPM), Program Evaluation and Review Technique (PERT), Work Breakdown Structure (WBS) to evaluate the preparation of aircraft maintenance activities and the Crashing method if acceleration is needed in completing maintenance activities in accordance with agreed agreement. With the preparation of good project management, it is possible to estimate the time and cost needed to complete a project so as to minimize delays and losses in completion. The project management planning used in this project resulted in an accelerated completion of 3.5 days with an additional cost of $ 8,958.23.

Determining aircraft maintenance times in civil aviation under the learning effect

PurposeScheduling of aircraft maintenance operations is a gap in the literature. Maintenance times should be determined close to the real-life to schedule aircraft maintenance operations effectively. The learning effect, which has been studied extensively in the machine scheduling literature, has not been investigated on aircraft maintenance times. In the literature, the production times under the learning effect have been examined in numerous studies but for merely manufacturing and assembly lines. A model for determining base and line maintenance times in civil aviation under the learning effect has not been proposed yet. It is pretty challenging to determine aircraft maintenance times due to the various aircraft configurations, extended maintenance periods, different worker shifts and workers with diverse experience and education levels. The purpose of this study is to determine accurate aircraft maintenance times rigorously with a new model which includes the group learning effect with the multi-products and shifts, plateau effect, multi sub-operations and labour firings/rotations.Design/methodology/approachAircraft maintenance operations are carried out in shifts. Each maintenance operation consists of many sub-operations that are performed by groups of workers. Thus, various models, e.g. learning curve for maintenance line (MLC), MLC with plateau factor (MPLC), MLC with group factor (MGLC) were developed and used in this study. The performance and efficiency of the models were compared with the current models in the literature, such as the Yelle Learning model (Yelle), single learning curve (SLC) model and SLC with plateau factor model (SLC-P). Estimations of all these models were compared with actual aircraft maintenance times in terms of mean absolute deviation (MAD), mean absolute percentage error (MAPE) and mean square of the error (MSE) values. Seven years (2014–2020) maintenance data of one of the top ten maintenance companies in civil aviation were analysed for the application and comparison of learning curve models.FindingsThe best estimations in terms of MAD, MAPE and MSE values are, respectively, gathered by MGLC, SLC-P, MPLC, MLC, SLC and YELLE models. This study revealed that the models (MGLC, SLC-P, MPLC), including the plateau factor, are more efficient in estimating accurate aircraft maintenance times. Furthermore, MGLC always made the closest estimations to the actual aircraft maintenance times. The results show that the MGLC model is more accurate than all of the other models for all sub-operations. The MGLC model is promising for the aviation industry in determining aircraft maintenance times under the learning effect.Originality/valueIn this study, learning curve models, considering groups of workers working in shifts, have been developed and employed for the first time for estimating more realistic maintenance times in aircraft maintenance. To the best of the authors’ knowledge, the effect of group learning on maintenance times in aircraft maintenance operations has not been studied. The novelty of the models are their applicability for groups of workers with different education and experience levels working in the same shift where they can learn in accordance with their proportion of contribution to the work and learning continues throughout shifts. The validity of the proposed models has been proved by comparing actual aircraft maintenance data. In practice, the MGLC model could efficiently be used for aircraft maintenance planning, certifying staff performance evaluations and maintenance trainings. Moreover, aircraft maintenance activities can be scheduled under the learning effect and a more realistic maintenance plan could be gathered in that way.

Maintenance of Composite-Based Aircraft Components and Structures through the Perspective of Aviation Maintenance Technicians in the United States

For the last three decades, the field of aircraft construction and manufacturing has been experiencing a significant change as the material of choice for aircraft construction has been continuously transitioning from metal to composite materials. This underlying change to the way aircraft structures and components are manufactured is propelled by composite materials’ intrinsic design and operational advantages. Nevertheless, as new technologies are introduced into the aviation industry, it is crucial to consider how all aspects thereof are affected, most importantly to ensure that safety is not compromised. As a critical part of the aviation industry and a key factor influencing the safety thereof, maintenance activities and certified aviation maintenance technicians (AMTs) need to be considered when evaluating the impact of the introduction of composite materials in the aeronautical field. Consequently, the conducted study specifically focuses on aircraft maintenance activities, especially as it pertains to the interaction of certified AMTs with composite materials. The goal of the study was to highlight and understand the opinions and perceptions of AMTs on composite materials and how, from a front-line perspective, aviation maintenance activities have changed with the introduction of novel materials. The input gathered from AMTs is a tool to understand potential pitfalls, deficiencies in training and resources, and safety threats from a maintenance perspective that may stem from the increased use of composite materials. With this purpose, certified maintenance technicians in the United States were surveyed and their responses were analyzed to identify recurring themes in the topics presented. Responses indicated issues related to formal composite-centered AMT training, knowledge, and resources available for composite maintenance.

An Assessment of Aircraft Maintenance Technician Competency

Aircraft maintenance activities are one of the most important criteria for the safe and effective execution of aviation operations., In aircraft accidents and incidents, maintenance factor is vital for the development of safety for organizations, authorities, and countries in the aviation field. Effective maintenance activities will also contribute to the costs of organizations by ensuring the safe operations of aircraft with people. Maintenance activities are carried out by maintenance technicians in areas such as hangars or aprons. Aircraft maintenance technicians' performance in performing maintenance activities directly impacts flight safety and technician safety, which in turn has a positive or negative impact on organizations. Improving technician competency assessment processes can reduce maintenance errors, improve technician performance, create positive impacts on safe and efficient flight operations, reduce maintenance costs and benefit of the entire aviation industry. Technician competency should be considered in performance evaluations and assignments by assessing at all levels with the compatibility of widely used human resources management methods. In this study, technician competency assessment processes are mentioned, the effects of these processes on aviation safety are explained and solutions are proposed to develop and apply the assessment processes.

Procedure structuring for programming aircraft maintenance activities

Purpose This paper aims to exemplify the use of project management tools in the scheduling of aircraft maintenance activities. This process is known as maintenance, repair and overhaul and it has gained importance within the aeronautical sector due to its expected growth in the coming years; however, it also faces increasing competitiveness in its market. This fact gives rise to the need of acting in maintenance management and seeking lower costs while maintaining the quality of the service provided. The purpose of this paper is to propose the structuring of a procedure that aims to reduce the total maintenance time (downtime) and guarantee the delivery of the aircraft on time. Design/methodology/approach The paper, through a case study at a Brazilian aircraft maintenance center, used critical path method and critical chain project management, the latter being derived from the theory of constraints, with the purpose of analyzing resources systematically and synchronizing the activities in the precedence network. Findings As a result, it is shown that downtime can be reduced from 11 to 5 days and improvements are proposed to achieve greater market competitiveness. Originality/value This paper demonstrates the competitive advantage that resulted from the application of project management tools in the aircraft maintenance planning and execution.

HAVA ARACI BAKIM FAALİYETLERİNDE DIŞ KAYNAK KULLANIMIYLA İLGİLİ EMNİYET TEHLİKELERİNİN BELİRLENMESİNE YÖNELİK NİTEL BİR ÇALIŞMA

Çalışmada hava aracı bakım faaliyetlerinin dış kaynaklardan tedarik edilmesi durumunda bu yönteme özgü olarak ortaya çıkması muhtemel emniyet tehlikeleri, söz konusu tehlikelerin kaynaklarının ve sonuçlarının neler olabileceği, emniyeti neden ve nasıl tehdit edecekleri araştırılmıştır. Çalışmada açık uçlu anketler aracılığıyla, amaçlı örneklem yoluyla seçilmiş bu sürece hakim olan teknisyen ve mühendislerden nitel veri toplanmıştır. Veriler tümevarımsal nitel analiz yöntemiyle analiz edilmiştir. Havayolu işletmelerinin bakım faaliyetlerini dış kaynaklardan tedarik etme maliyetleri azaltmanın önemli bir aracı olarak gördükleri, MRO’ların sunacağı fiyatın en önemli seçim ölçütü olduğu, MRO pazarında fiyatın temel rekabet aracı olduğundan MRO’ların önemli maliyet azaltma baskılarına uğradıkları ve bunların çeşitli emniyet tehlikeleri yarattığı tespit edilmiştir. Ayrıca dış kayna kullanımı bakım faaliyetlerin üretilmesi süreçlerinin ve bu faaliyetleri üreten örgütsel yapıların parçalanmasına neden olarak emniyet tehlikeleri yaratmaktadır

Risk assessment of fuel quantity indicator replacement in ATR 72 aircraft

Aircraft maintenance activities are rife with opportunities for error. The concurrent in-flight failure of all of the engines of a non-scheduled airline flight and the following list of human lives highlight one of these opportunities. As commonly recognized among flight operators, each flight safety agency follows the criteria of the International Civil Aviation Organization Annex 16 in which all the evidences of the technical investigation pave the way for avoiding future flight accidents or incidents. On the other hand, when the Italian penal procedure code was applied for the Tuninter aircraft ATR 72 (identification code TS-LBB) crash at issue on 6 August 2005 near Palermo (Italy), the investigation is also carried out for finding (if concurrent or not) the personal and professional responsibilities. This was the task of the first author (R.M.A.M.). Now, this article briefly reports the findings of the investigation and discusses more in detail how both human factors of design and human factors in the published instructions for the completion of a maintenance task contributed to this accident.

Manutenção Aeronáutica no Brasil: distribuição geográfica e técnica

As atividades de manutenção aeronáutica formam uma parte essencial da aeronavegabilidade continuada, tendo como objetivo, tanto na área civil quanto na militar, prover a total condição de serviço para as aeronaves. O crescimento do transporte aéreo no Brasil tem exigido uma indústria de serviços de manutenção aeronáutica capaz de apoiar tal processo expansivo, sem prejuízo para as condições de segurança de voo. Alguns dos trabalhos encontrados na revisão da literatura exploram a manutenção aeronáutica sob perspectivas que buscam melhorar a eficiência técnica do setor. Pelo exposto, o principal objetivo deste artigo é ampliar o conhecimento sobre o setor de manutenção aeronáutica no Brasil, explorando as informações providas pela ANAC, com o intuito de construir um panorama que revele a distribuição geográfica e técnica dos nichos de capacitação. Para tanto, inicia com uma exposição dos conceitos básicos da atividade de manutenção em geral e aeronáutica em particular. A seguir, é examinado o contexto regulatório brasileiro para a atividade de manutenção aeronáutica, com ênfase nos domínios de certificação. Ao final, examina-se a distribuição geográfica das empresas de manutenção aeronáutica no país, identificando a distribuição das empresas considerando-se os vários tipos de certificação técnica.

The Aircraft Maintenance Base Location Problem

Aviation authorities such as the Federal Aviation Administration (FAA) provide stringent guidelines for aircraft maintenance, with violations leading to significant penalties for airlines. Moreover, poorly maintained aircraft can lead to mass cancellation of flights, causing tremendous inconvenience to passengers and resulting in a significant erosion in brand image for the airline in question. Aircraft maintenance operations of a complex and extended nature can only be performed at designated maintenance bases. Aircraft maintenance planning literature has focused on developing good tail-number routing plans, while assuming that the locations of the maintenance bases themselves are fixed. This paper considers an inverse optimization problem, viz., locating a minimal number of maintenance bases on an Euler tour, while ensuring that all required aircraft maintenance activities can be performed with a stipulated periodicity. The Aircraft Maintenance Base Location Problem (AMBLP) is shown to be NP-complete and a new lower bound is developed for the problem. The performance of four simple “quick and dirty” heuristics for obtaining feasible solutions to AMBLP is analyzed.

Exposure to fall hazards and safety climate in the aircraft maintenance industry

Problem Falls represent a significant occupational hazard, particularly in industries with dynamic work environments. This paper describes rates of noncompliance with fall hazard prevention requirements, perceived safety climate and worker knowledge and beliefs, and the association between fall exposure and safety climate measures in commercial aircraft maintenance activities. Methods Walkthrough observations were conducted on aircraft mechanics at two participating facilities (Sites A and B) to ascertain the degree of noncompliance. Mechanics at each site completed questionnaires concerning fall hazard knowledge, personal safety beliefs, and safety climate. Questionnaire results were summarized into safety climate and belief scores by workgroup and site. Noncompliance rates observed during walkthroughs were compared to the climate-belief scores, and were expected to be inversely associated. Results Important differences were seen in fall safety performance between the sites. The study provided a characterization of aircraft maintenance fall hazards, and also demonstrated the effectiveness of an objective hazard assessment methodology. Noncompliance varied by height, equipment used, location of work on the aircraft, shift, and by safety system. Discussion Although the expected relationship between safety climate and noncompliance was seen for site-average climate scores, workgroups with higher safety climate scores had greater observed noncompliance within Site A. Overall, use of engineered safety systems had a significant impact on working safely, while safety beliefs and climate also contributed, though inconsistently. Impact on Industry The results of this study indicate that safety systems are very important in reducing noncompliance with fall protection requirements in aircraft maintenance facilities. Site-level fall safety compliance was found to be related to safety climate, although an unexpected relationship between compliance and safety climate was seen at the workgroup level within site. Finally, observed fall safety compliance was found to differ from self-reported compliance.