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The purpose of this paper is to present issues and challenges of scheduled maintenance task development within the maintenance review board (MRB) process, and to find potential areas of improvement in the application of the MSG‐3 methodology for aircraft systems.

The issues and challenges as well as potential areas of improvement have been identified through a constructive review that consists of two parts. The first part is a benchmarking between the Maintenance Steering Group (MSG‐3) methodology and other established and documented versions of reliability‐centred maintenance (RCM). This benchmarking focuses on the MSG‐3 methodology and compares it with some RCM standards to identify differences and thereby find ways to facilitate the application of MSG‐3. The second part includes a discussion about methodologies and tools that can support different steps of the MSG‐3 methodology within the framework of the MRB process.

The MSG‐3 methodology is closely related to the RCM methodology, in which the anticipated consequences of failure are considered for risk evaluation. However, MSG‐3 considers neither environmental effects of failures nor operational consequences of hidden failures. Furthermore, in MSG‐3, the operational check (failure‐finding inspection) is given priority before all other tasks, whereas in RCM it is considered as a default action, where there is no other applicable and effective option. While RCM allows cost‐effectiveness analysis for all failures that have no safety consequences, MSG‐3 just allows it for failures with economic consequences. A maintenance program that is established through the MRB process fulfils the requirements of continuous airworthiness, but there is no foundation to claim that it is the optimal or the most effective program from an operator's point‐of‐view. The major challenge when striving to achieve a more effective maintenance program within the MRB process is to acquire supporting methodologies and tools for adequate risk analysis, for optimal interval assignments, and for selection of the most effective maintenance task.

The paper presents a critical review of existing aircraft scheduled maintenance program development methodologies, and demonstrates the differences between MSG‐3 and other RCM methodologies.

DURING recent years many airlines have realised that overhaul time controls alone have had little success in controlling failure frequency. Considerable effort has subsequently been devoted to identifying and continuing those scheduled maintenance activities which are effective in protecting reliability characteristics, and identifying and discontinuing those scheduled maintenance activities which are ineffective in controlling reliability characteristics.

Very often it is not possible to recognise deterioration of failure resistance in complex devices while they are installed on the aircraft and out on the airline. In such cases operational failures may occur. The failures do not all occur at the same age, however, because the resistance to failure and the environmental stress of two pieces of nominally identical equipment are not the same.

This article surveys the literature dealing with theory and applications of life cycle costing (LCC). It deals with the literature published in the last 25 years and provides 667 references.

The aim of this study is to determine the variation of the different oil analysis instruments in terms of standard deviation and CV‐values, when measuring samples of fully formulated hydraulic and gear oils taken from working systems.

In this investigation, two different spectrometric techniques, inductively coupled plasma‐optical emission spectrometers (ICP‐OES) and rotating disk electrode‐optical emission spectrometers (RDE‐OES), have been studied to determine the instruments' precision of measurement and ability to measure the absolute level of contamination. The study was based on a series of measurements using artificial contamination mixed with oil.

The ICP has better precision of measurement of the two instruments, but cannot predict the absolute values of contamination when oil samples are only treated by organic solvent dilution if the samples include large or dense particles. It is therefore not too good, with the sample pre‐treatment method used, at detecting wear processes that produce dense/large particles, such as pitting failure. For instance, microwave‐assisted acid digestion could be used for sample pre‐treating to obtain accurate results in that case. It should, however, be able to detect wear mechanisms that produce small particles such as abrasive wear in any case. The ICP has a repeatability value of r=3 percent and a reproducibility value of R=12 percent for contamination levels of between 50 and 400 ppm and r=0.6  and R=2 ppm, respectively, at values below 50 ppm. The RDE cannot predict the absolute value of contamination if this includes large or dense particles if proper sample pre‐treatment is not used. It is therefore not good at detecting wear mechanisms that produces dense/large particles (if the oil samples are not pre‐treated properly) such as pitting but should be able to detect abrasive wear and similar processes that produce small particles in any case. The RDE's precision of measurement is not as good as the ICP, with a reproducibility variation of R=r=25 percent for contamination levels between 20 and 500 ppm and R=r=6 ppm for contamination level below 20 ppm.

Only the effects from lubricating oils are studied.

This study will significantly increase the industrial knowledge concerning measurement precision in particle contamination measurement systems.

No similar study is found.

Provides examples of duty variability based on field tests conducted during ordinary operating conditions. A severity‐based maintenance approach is introduced as complementary to the reliability‐centred maintenance initiatives currently being introduced in various mining companies. The essential component of this approach is a series of equipment monitors (called “dutymeters”) that continuously monitor and log the real duty on the machine as well as some machine parameters that can be used for machine health diagnostics. Describes application of this concept to a range of machinery including draglines, shovels, haul trucks and longwall equipment.

This study presents a reliability-based and sustainability-informed maintenance optimization model for telecommunications equipment. It considers several risk attributes associated with sustainability dimensions (i.e. social, economic and environmental aspects).

Many companies have developed long-term strategies to promote higher resource utilization, which has led to a paradigm shift in the role of maintenance. In parallel, reliability has been recognized as a fundamental factor in characterizing the optimal blend of maintenance strategies for a given system. It is essential for accurate failure prediction, which contributes toward more efficient use of all resources.

The corresponding subattributes are identified based on expert opinions and then incorporated into the proposed model. Subsequently, using the multiobjective particle swarm optimization (MOPSO), the proposed sustainability risks together with the maintenance costs are optimized, and the proper blend of maintenance strategies is identified.

Effective management of all human and natural resources, which are particularly emphasized by the concept of sustainability, has attracted much attention in recent years. However, contributions that effectively apply this concept in maintenance problems are very few and very few studies have attempted to quantify sustainability.

The purpose of this paper is to create a framework to provide a scalable maintenance program for unmanned aircraft systems (UAS) in order to choose the most suitable and feasible maintenance strategy in terms of reliability.

The paper opted for a reliability-centered maintenance-based approach to develop the framework using a UAS as the starting point of the research. A linear and user-friendly design of the methodology based on a Boolean flowchart was chosen in order to lead the analyst through the process avoiding as much as possible subjectivity decision-making issues. Finally, the framework was, on the component level, performed by a UAS company gathering feedback on its applicability.

An agile and structured decision-making framework for developing scalable maintenance program of UAS is provided. The proposed solution gives the opportunity to tailor the maintenance strategy to the technical characteristics, considering not only the single component but also situations and conditions in which the machine will operate.

Because of the chosen research approach, the framework is potentially applicable to every UAS. A first trial of the method was run on a multirotor vehicle equipped with eight electric brushless motors. Further studies focused on different UAS will be mandatory in order to obtain comparable and robust findings and a reliable approach.

This study offers a different scheme to elaborate a specific maintenance solution related to the characteristics of the system. It strives to remedy the drawbacks of the traditional approach for a manned aircraft not completely suitable for systems with such different functions, features and tasks. The authors believe that the method presented in this paper will provide a new selection tool for choosing maintenance actions based on the features of the UAS.

This paper provides a new and usable solution to include the maintenance actions in the management of pioneering products. In spite of the maintenance program representing an essential aspect to provide reliable assets, frameworks to create programs and to help manufacturers and users are still difficult to find or to apply to different UAS. This gap enhances the misunderstanding that the maintenance is not required or essential for the unmanned aircrafts management.

The design of the D.558 Skystreak in 1944 involved a full monocoque magnesium fuselage and there was a fear that a high‐temperature jet exhaust impinging on the structure might be unsafe. Tests in fact showed that magnesium due to its higher thermal diffusivity was safer than aluminium. Testing techniques for elevated temperature structures encompass a new field and as the methods of performing the tests have not become standardized, a wide variety of methods are being tried. A description of tests using the various methods tried by the authors of this paper are presented together with the reasons why the particular methods were chosen. Methods include a bank of furnace‐type gas burners, resistance heating techniques, heat blankets, lamp radiation and the Andersometer. Solar furnaces, shock tunnels, magnetohydrodynamic devices, plasma jets, etc., can be ruled out as the dimensions of the test article would be far too limited. Induction heating closely approximates the conditions encountered during aerodynamic heating, but cost and bulk of apparatus become a serious problem.

Catastrophic failures in high-reliability installations result from technical and human factors. The purpose of this paper is to use reports of the BP Texas refinery accident and the UK Buncefield oil storage explosions as the basis for exploring how protection and safety are managed in high-reliability manufacturing organisations in South Africa.

A survey of 21 high-reliability firms was undertaken to establish how firms perceived their safety and protection systems in relation to the findings of the Buncefield and BP Texas accidents. Interviews were held with staff in two firms.

The study identifies technical and behavioural shortcomings in managing safety and protective systems in manufacturing organisations. There are profound differences in perceptions of managers, supervisors and operators regarding a number of safety-related factors. Firms fail to identify all protective systems. Essential failure data for determining appropriate policies for failure finding are not collected.

Quantitative results are based on a relatively small sample and qualitative perspectives derive from two case studies.

Managers are unsure how protective devices should be managed. The paper highlights areas where significant improvements are essential if the South African firms are to meet developed world standards.

High-reliability organisations are obliged to minimise the possibility of serious incidents whose consequences may extend far beyond the physical bounds of the organisation.

Limited research has been published on the management of protective systems. This paper highlights a number of technical and behavioural issues that should be addressed for safe operation of high-reliability manufacturing organisations.