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Degradation of repairable components may not be similar after each maintenance activity; thus, the classic (traditional-time based) maintenance policies, which consider preventive maintenance (PM), age-based maintenance and overhauls to be done at fixed time interval, may fail to monitor the exact condition of the component. Thus, a progressive maintenance policy (PMP) may be more appropriate for the industries that deal with large, complex and critical repairable systems (RS) such as aerospace industries, nuclear power plants, etc.

A progressive maintenance policy is developed, in which hard life, PM scheduled time and overhaul period of the system are revised after each service activity by adjusting PM interval and mean residual life (MRL) such that the risk of failure is not increased.

A comparative study is then carried out between the classic PM policy and developed PMP, and the improvement in availability, mean time between failures and reduction in maintenance cost is registered.

The proposed PMP takes care of the equipment degradation more efficiently than any other existing maintenance policies and is also flexible in its application as the policy can be continuously amended as per the failure profile of the equipment. Similar maintenance policies assuming lifetime distributions are available in the literature, but to ascertain that the proposed PMP is more suitable and applicable to the industries, this paper uses Kijima-based imperfect maintenance models. The proposed PMP is demonstrated through a real-time data set example.

In this paper an experience dealing with the analysis of maintenance outsourcing by means of multi‐criteria decision methods (MCDM) is reported. In particular, the analytic hierarchy process technique (AHP) is used as a managerial decision support system to select the best alternative between different outsourcing contracts in terms of maintenance services. The proposed methodology has been tested on an industrial case study dealing with an important italian brickwork. This application shows how the AHP is able to support the choice of the correct level of the maintenance activities outsourcing. In particular, the hierarchic decisional structure developed represents an instrument able to give a well balanced synthesis of several different factors that must be taken into account during this type of decision problem.

This paper is a continuing exploration into facilities management (FM) strategy through the arrangement of its decision choices. The purpose of this paper is to identify the existence of FM operation strategy and to add empirical evidence to this subject to the field of FM and property management. Its main objectives are to gain insights into the arrangement of the FM strategic choices in operation and its relationship with business strategy.

The study investigated the configurations of operational approaches and activities that should reflect strategic decisions. The investigation was undertaken through a study of four reputed shopping malls located in Bangkok. The relevant data were collected through semi-structured interviews with the key FM persons of each case study, plus archival document searches, and observations of operational processes. Subsequently, the data were examined in a cross-case analysis to identify the key patterns of relationships between the FM operational arrangements and the business strategy of the mall.

This study found that the functional scheme of FM adopted in operations was deliberately related to the needs of business strategy and the operations of the given shopping mall. A range of strategic choices for FM operations was also found. Certain choices are shared among the case studies, while their arrangements varied according to the particular business strategy and context.

The number of case studies was rather limited, while the results were predominantly involved with a single type of facility.

The study identified the pattern of strategic choices entailed in the FM operations in shopping malls. The findings add to the understanding on FM strategy by widening the perspectives about the strategic choices of FM operations and how they are connected with the business strategy and operation model of retail estate. It adds empirical evidence and case studies regarding FM operations and its strategic features.

The basic organization of maintenance and overhaul is examined, with some notes about the aircraft in use, the Convair 240 and the Douglas DC‐3, DC‐4 and DC‐6, and the reasons for the maintenance on each type being carried out differently. Owing to the operating conditions of Sabena, with both long‐range routes and short‐range networks in Europe and the Congo, organization of maintenance presents special problems. The routine inspections on the DC‐3, Convair and DC‐6 are described separately in order to present a picture of the line maintenance of the Company. The DC‐3 is maintained on a 125/500/1,000 hour cycle, with a special major inspection at 3,000 hours; the Convair has a similar progressive scheme; while the DC‐6 is serviced on an alternating 75/150 hour cycle, plus certain progressive items, to a major inspection at 2,400 hours. Airframe overhaul—carried out on all types despite the progressive maintenance schedule for the Convair—occurs at about 10,000 hours. The power plant (or ‘quick‐change’) work, engine overhaul and accessory maintenance is described, but radio, radar and instrument inspection and repair are not covered.

THE structure and systems of the Hawker Siddeley 748 were designed with a prior knowledge of the type of inspection that would be required. The result is that structure and assemblies requiring frequent inspection are readily accessible. Where possible, proved components were used with known reliability ratings and this greatly increased the aircraft's serviceability.

The purpose of this paper is to provide a relatively straightforward approach of implementing standard statistical process control (SPC) concepts while instituting problem‐solving intonations in aero‐engine maintenance processes.

The inspection workflow approach is presented in order to aid in collecting and monitoring critical aero‐engine data. Observed defects are categorized according to a Pareto analysis assisted by a cause‐and‐effect diagram. A binomial process capability analysis is performed on nonconforming aero‐engines based on operating curves produced specifically for this case study. The time frame for experimental analysis is reflected in a span of six months.

It is found that a significant number of aero‐engines may be benefited by entering a more progressive maintenance program relying on predictive maintenance on the way to establishing a more effective Total Productive Maintenance scheme.

The case study showcases an approach to aero‐engine rejection statistical rates by accepting the fact that maintenance process may not be viewed as a process that may be limited to constant sampling.

For a long time, total quality management (TQM) tools have been deeply rooted in design, manufacturing and assembling of airliners and jet fighters alike. However, a comprehensive study focusing on the maintenance function of such complex machines may prove worthwhile now that an unstable global economy may prohibit extensive replacement of aging flying fleets.

With the lack of a prior practical unfolding in the field of genuine aero‐engine maintenance, this presentation aims to fill in the gap for engine rejection treatment. The variant operating curve notion introduced in the text is also a unique idea espoused for variable sampling situations when a binomial distribution is adopted.

This paper highlights how technical devices last in organizations. Instead of focusing on the usual implementation or short-term post-implementation phases, this study aims to explore what happens to established technical devices.

The authors build on a 10-year in-depth longitudinal case study examining a CRM package, a type of Enterprise Resource Planning system specialized in customer relationship management, in a door-drop advertising company. This case is based mainly on 35 interviews and four weeks of non-participant observation, made over three different periods.

Drawing on the literature on drift and maintenance, this study investigates two tensions foregrounding lasting: one regarding the degree of human intervention on the technical device (object being maintained vs object maintaining itself) and one regarding the relationship to the initial expectations towards the technical device (relinquishment of certain hopes vs regeneration of interests). This case combines these tensions and allows to highlight four alterations in the CRM system to show how apparently stable devices keep on changing.

In a time of resource exhaustion, it is important to reflect upon our relationships to information technology and their modalities of lasting. By stressing that uses emerge from relinquishment and reduction, the authors wish to help organizations move towards more sustainable engagement with their technical devices in the long run.

Lasting is not just a matter of being maintained in a context of threat but also builds upon the capacities of a technical device to maintain itself. The self-alteration dynamics that the authors come up with, shedding and ramification, offer a dedramatized interpretation of maintenance that complements studies on institutional maintenance. The results also contribute to studies on technological drift. The authors stress that drifts are triggered by ties that run out, in particular, discontinuation of maintenance in the system. The durability of technical devices in organizations thus does not consist in always more uses or functionalities, but is also made of reductions and relinquishment.

In a modern commercial airliner programme the ability to produce a technically good product at the right time is not enough. Efficient programme management, in all its facets, is absolutely essential to ensure a proper return on the big investments required and the smooth and progressive deployment of financial, plant and manpower resources through each programme to the next.

While steady-state analysis is useful, it does not consider the inherent transient characteristics of repairable systems' behavior, especially in systems that have relatively short life spans, or when their transient behavior is of special concern such as the motivating example used in this paper, military systems. Therefore, a maintenance policy that considers both transient and steady-state availability and aims to achieve the best trade-off between high steady-state availability and rapid stabilization is essential.

This paper studies the transient behavior of system availability under the Kijima Type II virtual age model. While such systems achieve steady-state availability, and it has been proved that deploying preventive maintenance (PM) can significantly improve its steady-state availability, this improvement often comes at the price of longer and increased fluctuating transient behavior, which affects overall system performance. The authors present a methodology that identifies the optimal PM policy that achieves the best trade-off between high steady-state availability and rapid stabilization based on cost-availability analysis.

When the proposed simulation-based optimization and cost analysis methodology is applied to the motivating example, it produces an optimal PM policy that achieves an availability–variability balance between transient and steady-state system behaviors. The optimal PM policy produces a notably lower availability coefficient of variation (by 11.5%), while at the same time suffering a negligible limiting availability loss of only 0.3%. The new optimal PM policy also provides cost savings of about 5% in total maintenance cost. The performed sensitivity analysis shows that the system's optimal maintenance cost is sensitive to the repair time, the shape parameter of the Weibull distribution and the downtime cost, but is robust with respect to changes in the remaining parameters.

Most of the current maintenance models emphasize the steady-state behavior of availability and neglect its transient behavior. For some systems, using steady-state availability as the sole metric for performance is not adequate, especially in systems that have relatively short life spans or when their transient behavior affects the overall performance. However, little work has been done on the transient analysis of such systems. In this paper, the authors aim to fill this gap by emphasizing such systems and applications where transient behavior is of critical importance to efficiently optimize system performance. The authors use military systems as a motivating example.

Maintenance organizations continue to be under pressure to systematically eliminate maintenance wastes and deliver services that their customers value. To this end, maintenance managers are implementing lean maintenance practices. But how does one consistently estimate the leanness of these practices in their organization? The purpose of this paper is to develop a framework for a metrics – referred to as the lean maintenance index (LMI) that can help managers estimate the leanness of maintenance practices.

Based on a comprehensive review of literature in the domain, this study identifies four factors and nineteen subfactors that are essential for the success of a lean maintenance program. A fuzzy-set-theory-based assessment framework is developed that can be used by an in-house team to measure the degree of implementation of lean maintenance practices in their organization. The authors applied the framework to a maintenance workshop that services diesel engines and other prime movers.

The framework provides maintenance managers valuable insights to help identify the strengths and weaknesses of their organization vis-à-vis their maintenance practices, thus enabling them come up with a firm action plan for future process improvements.

This paper adapts the concept of agility and readiness to maintenance work. A key contribution of this study is the identification of factors and subfactors that forms the basis to estimate the leanness of maintenance practices in an organization. Another contribution is its application to a large maintenance workshop that demonstrates the ease of its implementation. Future research in this area can help identify more factors and subfactors and thus improve the estimation of leanness.