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The purpose of this paper is to provide a platform for discussion on the problem of no fault found (NFF) events which continues to plague maintenance operations of complex engineering systems.

The research has been collated from many sources: academic literature, industrial discussions and the authors’ experiences. The study defines the NFF problem, its causes, impacts and costs as well as an evaluation of the available scientific research.

The paper identifies a continuing serious problem with NFF; it is not just a technical problem but also encompasses organisations, culture and behaviours. Focusing only on one of these at a time is no longer enough to solve the NFF problem in modern maintenance operations and solutions will require each category to be addressed as an integrated problem.

The overall value is a detailed picture of the NFF field seen from both an industrial and academic viewpoint. The originality of the paper is that it articulates and organizes the existing knowledge concerning the NFF phenomena, the value of which is to identify gaps in existing research and knowledge.

Chris Labarte has been appointed Area Sales Manager with Alpha Metals, one of the leading suppliers of solder products and related materials.

Examines the use of acoustic emission techniques for monitoring part mating during the assembly process. The frequency recorded during a peg insertion is compared with known frequencies of successful peg insertion by a microcomputer. This allows unsuccessful alignment to be readjusted which being monitored by a digital sound analyzer. Outlines the concept of part mating which is based on the peg‐in‐hole theory developed by Simunovic and describes an acoustic emission monitoring system. Concludes that acoustic monitoring provides a relatively low cost, low complexity system for part mating monitoring but may have limitation in manufacturing environments where there is excessive background noise or machine part vibration.

The use of lead in electronics assembly operations has come under scrutiny due to health and environmental concerns associated with lead exposure. Lead is one of the most useful metals in modern industry; however, lead has the dubious distinction of being one of the most toxic of metals. Increasingly restrictive government regulations on the use of lead are hastening the search for feasible alternatives to tin‐lead solder alloys. From an electronics assembly standpoint, there is a desire to replace lead bearing HASL (hot air solder levelling) coatings with a metallic, lead‐free alternative. To answer these needs, Motorola have developed a lead‐free, immersion plating technology for the surface finish of PCB printed circuit board bond pads. The Motorola development work has focused on the metallurgical system of tin‐bismuth, which is a simple eutectic system similar to that of tin‐lead, featuring a minimal number of phases and a wide operating window.

The successful first firing of a fully guided air‐to‐air test vehicle based on the Short Range Air‐to‐Air Missile (SRAAM) was recently carried out by Hawker Siddeley Dynamics from a MOD (PE) Hunter aircraft over the Aberporth range. The launch was the first to be carried out under operational conditions and follows successful ground and air dispersion firings.

Production of a high variety of products introduces complexities in the quality processes involved in a manufacturing system. Previous methods of quality assurance and control are not sufficient to manage the quality characteristics that are significant to each customer. Research into quality management for these environments has been isolated and segmented. No framework exists to holistically manage product quality within an unstable manufacturing environment. This paper seeks to propose a method of holistically managing product quality in a manufacturing environment with high customer input and product variety. The development of a reconfigurable inspection apparatus is discussed as a technological requirement for performing the quality control aspect of the management system.

The quality requirements of modern manufacturing systems were established. The required flow of information for an advanced quality management system was proposed and compared to the information flow in a traditional quality management system. The developed reconfigurable inspection apparatus was tested by performing an inspection of a product configuration within a part family of torches. Commercial products were used for the construction of the apparatus, including the electrical and software aspects. A commercially available simulation package was used to simulate the effects of a random customer order on production flow whilst implementing the developed apparatus.

Modular inspection equipment would prove essential to the implementation of quality control when considering advanced manufacturing environments. An overall management system is also needed for the verification of product quality as per individual customer requirements. Quality needs to be integrated as per TQM principles.

Traditional quality control tools may not always be applicable for unstable market demand. The research indicated the required progression of quality systems to successfully manage the quality for advanced manufacturing. The widespread availability of commercial components for the inspection apparatus verified the shift in supplier focus to meet the needs of shifting manufacturing requirements.

The proposed approach to assure and control quality, as well as the researched inspection apparatus, provided the capability of being implemented in a manufacturing environment that involves production of a variety of products as opposed to being limited to one part family. The use of modular mechanical, electrical and software components will ease the implementation of reconfigurable inspection stations into existing manufacturing setups.

Research indicated that quality systems need to be further developed for assuring and controlling product quality of products with high customer input. No system existed that could holistically consider the quality requirements of a product from design to delivery.

The transition to complex printed board assemblies in modern high technology equipment is described. These low voltage, densely packed PBAs with their decreasing insulation paths, manufactured for greatest speed with highly activated solder fluxes, demand both awareness and action to achieve the degree of cleanliness compatible with reliability requirements. This paper sets forth activities under way in Australia to define and adopt cleanliness Standards for use throughout the nation's manufacturing industry. It identifies and defines cleanliness and methods used to achieve and measure contamination that is introduced during PBA manufacture.

The purpose of this paper is to apply an on‐line automatic inspection and measurement of surface defect of thin‐film transistor liquid‐crystal display (TFT‐LCD) panels in the polyimide coating process with a modified template matching method and back propagation neural network classification method.

By using the technique of searching, analyzing, and recognizing image processing methods, the target pattern image of TFT‐LCD cell defects can be obtained.

With template match and neural network classification in the database of the system, the program judges the kinds of the target defects characteristics, finds out the central position of cell defect, and analyzes cell defects.

The recognition speed becomes faster and the system becomes more flexible in comparison to the previous system. The proposed method and strategy, using unsophisticated and economical equipment, is also verified. The proposed method provides highly accurate results with a low‐error rate.

In terms of sample training, the principles of artificial neural network were used to train the sample detection rate. In sample analysis, character weight was implemented to filter the noise so as to enhance discrimination and reduce detection.

The paper describes how pre‐inspection image processing was utilized in collaboration with the system to excel the inspection efficiency of present machines as well as for reducing system misjudgment. In addition, the measure for improving cell defect inspection can be applied to production line with multi‐defects to inspect and improve six defects simultaneously, which improves the system stability greatly.

The Hybrid Microelectronics Laboratory in the Bradley Department of Electrical Engineering at Virginia Polytechnic Institute and State University (VPI & SU), also named Virginia Tech, was established during the 1979–1980 academic year in order to provide classroom/laboratory instruction and research capabilities in the area of hybrid microelectronics. The laboratory was initially designed for the hybrid and thick film areas of microelectronics. Thin film design and fabrication capability was added in the Fall Semester, 1987. Currently, efforts are under way to develop the area of monolithic diffusion and processing of semiconductor wafers using both elemental and compound materials, initiated in the Fall Semester, 1991.