Reliability-Growth Programmes For Undersea Communication Systems

This paper deals with the unique problems encountered when managing reliability growth programmes on expensive capital equipment components destined for use in a relatively inaccessible environment. Continuous operation of these components in predominantly non-redundant configurations is required for up to 25 years; and repair costs and/or lost revenues incurred by single failures at anytime during this period can amount to several $100 000. After a brief review of the history and philosophy of reliability growth programmes on components for coaxial cable systems, the planning, development, and implementation of reliability assurance procedures for undersea systems designed for 1.3 μm optical transmission at 280 Mbit/s are addressed. The challenge involved in proving electro-optic and electronic components suitable for undersea optical PCM systems is not to be underestimated. Even in a relatively benign environment, these systems have specific problems with respect to operating temperatures, voltage stresses, heat dissipation factors, and the lack of escape routes for trapped contaminants. The components themselves are not only relatively new, or just emerging from the development phase, they also demand innovative reliability assessment techniques because of the inadequacy of traditional methods of accelerated testing. This paper gives an insight into some of these problems from a reliability management viewpoint. It is increasingly evident that QC and RA programme leadership cannot now, if it ever could, be accomplished without detailed knowledge of sophisticated component design.