Abstract
Long-term support agreements such as availability-based contracts are often associated with the servitization of business models in such sectors as defence aerospace. In practice, there is no unambiguous way of linking availability and service outcomes from an operational perspective; rather, the focus tends to be placed almost exclusively on product-related metrics. To address this gap, this paper outlines a conceptual model of how advanced service outcomes should be delivered under an availability-based contract for defence avionics. The model is grounded on empirical evidence gathered through an in-depth case study in the UK defence sector. The research is one of the first attempts to shift the focus away from a notion of availability as a property designed into a piece of equipment, and to detect its emergence from the interactions between relevant socio-technical elements within the underpinning advanced service delivery system, or Product-Service-System (PSS), identified by analysis of empirical data. This research provides insights into where action should be taken within a PSS that would be difficult to obtain from the analysis of field reliability data alone. It also provides a conceptual model that can assist the formulation of scientific models based on quantitative data such as multi-echelon inventory systems for repairable items. While the transferability of the findings is limited by the specificity of the case, a detailed description is provided to facilitate comparison with other cases.