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Applied Research Methods and Methodology: A PhD Thesis on Product Service Systems and Cost Estimation

The Representation of an Advanced Service delivered by a Product Service System – A Qualitative Model of Avionics Availability

A lot of the ideas behind “Methods and Meaning” stem from the time of my PhD preparation and some have found their way into the thesis – you may find them in particular in the Methodology section.

This post contains excerpts from the Thesis and the whole document can be downloaded here. They may be of interest for you when you are looking for:

  • how to structure a thesis;
  • research methodology and methods, in particular related to qualitative data;
  • process mapping in combination with interviews;
  • examples of Product and Service combinations, in Product Service Systems;
  • examples of performance-based contracts as in contracting for availability;
  • the reverse supply chain;
  • an overview of cost estimation techniques.

The structure of the thesis

My thesis is built of six parts with each structured into chapters and sub-chapters. Inspired by “The field guide to undersstanding human error”[1]Sidney W.A. Dekker (2006): The field guide to understanding human error. Aldershot, England, Burlington, VT: Ashgate. I have summarized each part at the beginning so that readers can jump to the part they are most interested in.

Part I Introduction

Presents the background, motivation and scope for this work. Focus is on the
trend for availability-based contracts that are delivered by Product Service
Systems (PSS) and in particular the Typhoon Availability Service contract that
was awarded to BAE Systems. This section specifies the aim of the research
which is to provide an approach to integrate social and technical aspects in the
representation of an existing PSS as a foundation for costing advanced services, in
particular avionics availability. Furthermore, definitions of core concepts used
throughout the work such as systems, qualitative models, advanced services, and
cost-related subjects are provided.

Part II Literature Review

Offers a critical review of the literature on PSS and cost modelling for PSS at the
interface between engineering and management. Gaps and mismatches in the
literature are identified that lead to the proposal of a process-based
representation of a PSS considering the flow of information and material to
represent the context availability is delivered in. Part II concludes by highlighting
the need for understanding socio-technical systems to generate a meaningful cost
estimate of a PSS delivering advanced services.

Relation of findings and identification of mismatches.

Part III Research Methodology

Represents one of the main contributions of the thesis by structuring and
describing ways for how to gain knowledge about a PSS
. The research
methodology relevant to the nature of PSS as a socio-technical system is
discussed along with a review on how methodological aspects are addressed in
the literature
on cost modelling and PSS. Also specifies the selection of
standpoints taken in this research considering the philosophical foundation,
research type, research strategy and methods for data collection and analysis.

Part IV Empirical Study

Describes what was done within the research and presents the results. The case
study setting centred on the delivery of an exemplar piece of avionics equipment
by BAE Systems and GE Aviation to the UK Royal Air Force is described, as well
as a detailed account of how data was collected and analysed. Results are then
presented from a functional perspective identifying ‘Analysis & Optimisation’,
‘Administration’ and ‘Delivery’ functions and an organisational perspective
showing the links between GE Aviation, BAE Systems and the Royal Air Force.
The results show distinctive similarities and differences between GE Aviation
and BAE Systems relating to a variety of parallel contracts, organisational
segmentation and tensions between relationships and contractual obligations.

Part V Discussion

Compares the findings from the empirical study with the literature on PSS and
cost modelling. It is shown that aspects of the results such as multiple parallel
outputs that interfere with each other have also been observed in the literature on
service delivery. However, in the literature on cost modelling for PSS these
findings find no consideration. Part V clarifies that within a PSS the costs of the
delivered outcome should not be modelled as a summation of features of its
constituent elements, but as an emergent property of the whole system. In
addition, the contribution of the findings to the existing body of literature is
, namely the representation of context as a necessity to attribute costs
within PSS.

Part VI Conclusion

Demonstrates how the research aim was met through the outline and application
of a suitable methodological approach to an existing PSS. In this way the relevant
system delivering avionics availability was identified and a representation of
such system provided. The contribution of this work to the existing body of
knowledge is illustrated
through specifying “what is a PSS” and “how to know
about PSS”
. Finally, the author’s reflections on the research are presented along
with suggestions for future work.

Research aim & objectives

This thesis contributes to the creation of a proof of concept cost model that is methodologically equipped
to deal with long-term availability-type contracts.


The aim of this work is to provide an approach to integrate social and technical
aspects in the representation of an existing Product Service System (PSS) as a foundation for costing
advanced services, in particular avionics availability.


The conceptual integration of products and services

Through the literature, the flow of information, knowledge and material between activities were identified as a common ground of products and services.

The identification of characteristics of PSS as socio-technical systems

It is characteristic of PSS delivered by socio-technical systems that outcomes cannot be traced back through direct cause and effect relationships. Rather, outcomes have to be considered as emergent properties that can only be explained through a holistic system analysis. However, complete knowledge cannot be attained in socio-technical
systems. These characteristics of socio-technical systems, underline the need to focus on the defensibility of a model rather than its assumed comprehensiveness and closeness to ‘reality’.

An outline for a methodological approach to investigate and represent the PSS as a socio-technical system.

Ways of knowing about social phenomena and methodological concepts are identified through the discussion of literature including the social sciences. The proposed methodology follows a selection of philosophical foundation, research types, research strategy, methods for data collection and methods for data analysis. To reflect the social aspects of PSS, qualitative data collected from interviews and documentation were considered appropriate in the given context. Process mapping, using the IDEF0 standard and diagrams following the FRAM were identified as suitable methods for representing the delivery of avionics availability. The methodology discussed and methodological approach followed represent a major move away from most of the literature on cost modelling which tends to focus on the quantitative analysis of quantitative product-related data.

The application of that approach to an existing PSS that delivers avionics availability

Organisational units, activities, locations and functions were identified as relevant system elements.

Relationships between the relevant system elements in terms of documentation, IT systems, material exchange and personnel moving between locations were identified.

The system boundaries were found to be blurred due to the overlap of processes and activities that contribute to the delivery of avionics availability and other outcomes. Hence, it is suggested to distinguish between what is ‘inside’ and what is outside ‘the system of interest depending on the ability to take action on the elements or links identified.

The representation of the PSS delivering avionics availability in a qualitative model

This objective was achieved through multiple maps which loosely follow the IDEF0 standard and a FRAM diagram. Three perspectives were shown:

  • an organisation-centred view,
  • a functional view, and
  • a specific scenario blending functional and organisational viewpoints in the FRAM diagram.
The functional view of the Product Service System of Interest.

Title image: By Jürgen (based on Radziwill), The red aicraft

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1 Sidney W.A. Dekker (2006): The field guide to understanding human error. Aldershot, England, Burlington, VT: Ashgate.

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