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This report describes a new system for descaling turbine blades which, by a combination of chemical and mechanical action, produces a clean smooth surface, suitable for penetrant inspection. Its development provides a solution to the problem of chemical attack on intermetallics in precipitation hardened nickel and cobalt base alloys by the conventional descaling sequences. The project study leading to the selection of the process is summarised, the development of the method, which is based on the use of a vibrated insoluble particulate burnishing medium used in conjunction with a hot chemical chelating solution, is described and typical results are given. Before proceeding to works trials of a new process, its technical effectiveness and any adverse effects on the substrate or the environment must be evaluated, in order that some estimate of its commercial viability can be made. It has been confirmed that the process cleans effectively and produces a satisfactory conditions for penetrant inspection. No adverse effects on surface profile or dimensions, for example, on the firtree roots of typical turbine blade, on alloys or protective catings, have been found. It has been verified that particles of the medium which may inadvertently remain in blade cooling passages after processing will not lead to local high temperature corrosion during subsequent operation. Chemical vibro‐descaling is also a suitable process to prepare components with oxide films for subsequent operations such as welding, heat treatment or surface treatment. Thus, the process, which is environmentally relatively benign, achieves its objective economically and without deleterious effect on the workpiece.

THIS paper deals, in the widest sense, with the operational aspect of sealants in relationship to their uses in the construction of integral fuel tanks. It should be borne in mind, however, that on modern aircraft, particularly those with pressurised hulls, there are other applications equally as important.

FOR the purpose of this paper discussion is only centred around rubber mouldings for various purposes. Sealants, adhesives, tyres etc. are covered elsewhere in the symposium.

THE advent of the integral fuel tank over twenty years ago presented considerable sealing problems, due to both deficiencies in design and lack of suitable sealing compounds.

A new corrosion protection system developed at B.A.C. Weybridge was first introduced on Vanguard aircraft and has remained in use almost unchanged up to the VC10 and B.A.C.1 11 aircraft which are being produced at this time. The system represented a complete change from previous ones, both in materials and methods of application and was the result of a very considerable amount of research into the limitations of the protective methods used up to that time. Through these investigations it became evident that insufficient emphasis had been placed on the importance of organic materials in corrosion protection and that the paints then in use failed to give satisfactory service due to lack of adequate‐fluid resistance and an inability to withstand repeated flexing and straining of the metal substrate without cracking of flaking. Hence the paint had to be resistant to all anticipated contaminants, including freight spillage, over the entire temperature envelope of the aircraft and had to be sufficiently adherent and flexible to withstand deformation of the substrate up to the point of metal failure. Long term protection from corrosion and compatibility with other forms of protection e.g. sealants, jointing compounds, etc. was also required, as well as an ability to withstand casual damage during service and maintenance. This lead to the decision (hat the Vanguard was to be an all‐painted aircraft and that the many and often conflicting requirements of the paint could only be met by a polyamide‐cured epoxy material. Having thus established the basic concept, consideration can now be given to the detailed requirements.

The intent of this chapter is to examine the historical and present-day intersections of injury, impairment, pain and risk-taking in the Paralympic Movement. While much has been written about injuries that end an athlete’s career, far less consideration has been given to how an injury might launch a sports career. In this chapter, I explore the experiences of athletes for whom injury and sports participation are fundamentally entwined.

To accomplish this, I draw on sociological literature on sport and injury, psychological literature on identities and sport retirement and feminist disability theories. The discussion is further enriched by interviews with Paralympic athletes and informed by own experience as a researcher, guide and volunteer in the Paralympic Movement.

This work illustrates how systems of representation intersect to (re)produce identities. This includes demonstrating how some individuals use sport as a means of claiming an athletic identity while distancing themselves from devalued disabled identities and the subsequent impact this can have on their psycho-social well-being.

This chapter demonstrates how sociologists of sports can engage with critical disability scholarship to deepen understandings of how and why individuals with impairments enter into sport and their experiences therein.

Every paper needs a theme. Luckily, the venue defines the theme for me; how did the initial conditions at Stanford affect the development and diffusion of population ecology as a theoretical research program. I use the term theoretical research program reluctantly, especially considering the context of the department of sociology at Stanford University during the 1970s and 1980s (Lakatos & Musgrave, 1970). Nonetheless, I believe that population ecology can be usefully described as such. It is not a theory but rather a collection of theories developing over time with progressive problem shifts. There are methodological rules that define what paths of research to pursue and to avoid (Pfeffer, 1993, p. 613).

The macroenvironment constitutes a widely acknowledged source of firms’ risk in international business. A substantial body of research on macroenvironmental risks encapsulates a variety of measurement approaches, antecedents, and managerial consequences. However, a review of established macroenvironmental risk measures reveals that these measures strongly focus on the quality of the macroenvironment, assuming a rather static perspective and mainly excluding dynamic aspects. Building on prior research on macroenvironmental risk as well as on environmental dynamism, we argue that macroenvironmental dynamism – i.e. the frequency, intensity, and predictability of macroenvironmental variation – is a pivotal source of risk in international business, which so far only received limited attention. Moreover, we suggest that macroenvironmental dynamism influences firms’ risk management activities, a measure we use to empirically investigate firm implications of macroenvironmental dynamism. We explore this effect using primary survey data on risk management activities from 158 foreign subsidiaries in six emerging countries and secondary data on the macroeconomic context in these countries. We find evidence that macroenvironmental dynamism, if compared to macroenvironmental quality, exerts a strong influence on firms’ risk management activities. Our findings enhance the understanding of the dynamic nature of macroenvironmental risk in international business as well as provide a concept to more comprehensively measure macroenvironmental dynamism that future research can build upon.