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The functionality and reliability of an overhauled aero-engine is determined by all configuration changes in the overhaul process. Identifying, recording, auditing, tracking and tracing of configuration modifications are significant and meaningful. Considering the barriers to these goals, this paper aims to put forward an approach to configuration management in the aero-engine overhaul process.

The overhaul configuration management model is proposed to describe an aero-engine’s configuration evolution trajectory in the overhaul process. The controlling and auditing procedures are put forward to control and audit parts’ return-to-zero statuses and overproof statuses. And some searching algorithms are also designed to enable tracking and tracing of the configuration status along the time coordinate, or get a snapshot of an aero-engine’s configuration at a certain time. The above model, procedures and algorithms have been implemented and adopted to fulfill the configuration management requirements in the aero-engine overhaul process.

The approach is effective in identifying, recording, controlling, auditing, tracking and tracing configuration changes in the overhaul process.

The approach’s implementation and adoption present a practical example for aero-engines’ configuration management issue in the overhaul process.

The work proposes an original aero-engine configuration management solution for the overhaul process and enables a reliable and accurate configuration management mode.

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.

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.

The Civil Aviation Authority has published the third edition of Aeronautical Engineering Certificate: Syl‐labus of Examinations (CAP 416)

Nowadays, a large amount of data related to aero engine in various types can be created in a single day and it is very important to well organize and store these data. The paper aims to discuss this issue.

This paper puts forward the problem of data management with the fast development of aero engine and sets the compression system as an example to see the inner relationships of data from the initial design procedure to the final operation and maintenance part. There are five principles, namely digitization, accuracy, normative, integrality and validity, involved in managing the data effectively.

These data resources arranged according to the five principles can be well organized and better used.

At the end, the top design of aero engine data sharing platform is investigated and five layers including data layer, data access layer, communication layer, business logic layer and application layer are designed and presented to support the platform.

THE successful operation of civil aircraft—in this country, at any rate—depends to a very large extent on the efficiency of the ground engineer. Anything that tends to raise the standard of ground engineering, whether it be by way of improving the knowledge of existing, or of providing a source of knowledge for prospective, ground engineers, must be of service to civil aviation generally.

WHEN man invented the wheel, bearings were introduced into civilization and every machine since devised incorporates, in some form, means of sustaining a loaded member in motion by another fixed member. It is not surprising, therefore, that examination of bearings forms a high proportion of all engineering inspection and the phrase “to look at the bedding of the bearing” is probably one of the oldest in engineering practice. During recent years, particularly in the aircraft industry, developments have taken place in bearing design and bearing metals which require an inspection technique differing from conventional methods that served well when loadings were comparatively low and factors of safety high. Desirable clearances and surface condition of the earlier alloys will not answer at all well for some new bearing materials; while on the other hand defects such as minor cracks, which were very dangerous in white metal, have been proved by experience to have little or no effect on some heavily loaded lead bronze bearings.

The use of SKF roller screws is said to be helping Aviall Caledonian Engine Services Ltd, of Prestwick, one of the world's foremost aero engine overhaul companies, to reduce the turnaround time for engine rebuilds from 56 days down to just 35. The reliability, performance and predictability of the roller screws are proving to be a major factor in the company's development plans.

Normalair‐Garrett Ltd., (Stand No. N31) part of the Westland plc Group of Yeovil, Somerset, is exhibiting a wide range of products which demonstrate the company's diverse capabilities in control systems and precision components for the aerospace industry.

In the production and overhaul of aero engines chemical and electrolytic surface treatment processes such as electrolytic degreasing, chemical and electrochemical etching, chemical descaling and chemical stripping of thermally sprayed coatings are used. In the course of some of these processes the heat resistant nickel and cobalt base alloys found in the “hot end” of the newer gas turbines are attacked. These superalloys have a common characteristic, namely, they are precipitation hardened. The alloying elements added for this purpose give rise to intermetallic compounds (carbides, nitrides, carbonitrides) which appear as inclusions of various shapes and sizes within the grain or at the grain boundaries. The conclusion from this work is that these intermetallics present as separate phases can be dissolved out by oxidative attack leaving pits. The separate processes and their objectives are detailed. It is shown in which process stages and in which solutions attack occurs. The inclusions have been analysed and the nature of the attack is illustrated. We conclude from this work, which has embraced seven nickel and cobalt base materials, that certain processes or process steps cannot be permitted on these alloys. For cleaning and etching alternative processes are given. For descaling a new compatible process was evaluated and will be discussed in a second report.