Paper 6: The Philosophy of Failure in Engineering Systems

Abstract

The possibility of failure and the consequences of failure are present in the mind of the engineer. The designer counteracts both to the best of his ability, taking into account the processes involved, material behaviour, cost, and delivery schedules. The technique of including an intentional weak link to minimize the consequences of failure is well known. Similarly, by using a number of machines instead of one, failure will cause reduced performance rather than complete loss. The use of stand-by machines and redundancy have thus become established engineering methods. The advent of nuclear power has led to the development of safety systems in which total failure cannot be tolerated. Similar duties in which failures must not occur exist in aircraft control systems. These duties have led to the development of precise methods of analysing safety. The success of the analyses depends upon the accurate reporting and cataloguing of product failures. This emphasizes the increasing importance of the service department function. Significant increases in product reliability have been obtained by providing the designer with development testing results, service department experience, and a theoretical analysis of failure probabilities.