We have found tie-over bolster dressings and basting sutures to be unnecessary in our series of small FTSG. This technique saves time and material and minimizes handling of the graft.

Most oil and gas executives and financial analysts have long believed that minimizing the time to first oil is one of the most important parameters to maximize the economic value of exploration and production (E&P) projects. This belief has driven project teams and oil company executives to push ever faster schedules. Our data show that chasing fast project schedules inadvertently destroys more value than it creates. We use a detailed database of oil and gas projects to conduct a rigorous statistical analysis, comparing project economics promised at sanction to the actual results achieved. Using performance data from the database, we can statistically quantify the change in expected outcomes (cost, production, reserves), and therefore the net present value (NPV) realized, as a result of different schedule targets. The results show that chasing aggressive first oil dates has a consistent negative effect on NPV because of worse than expected cost and production attainment. These effects are more damaging than the loss of value that occurs if a project is slowed down early in the project cycle to improve the quality of front-end preparation and planning that helps to mitigate cost and production attainment shortfalls. When speed becomes paramount, reservoir appraisal and project definition phases are shortened projects proceed without high-quality basic subsurface data, and often short-cut crucial planning phases. As the quality of data and planning degrades, teams are forced to make more assumptions, which increases uncertainty in cost, production, and reserves estimates. During execution, these major uncertainties, along with incomplete data and planning, drive cost growth, reserves downgrades, production shortfalls and, ironically, schedule slip. The poor than expected outcomes have a negative influence on the project economics, but are often ignored by economic models. In all projects there are choices to be made that lead to trade-offs between cost, schedule and production. Many companies prioritize their focus primarily on meeting their schedule and then, cost targets in order to achieve maximum economic returns. The reason production is often not part of the trade-off is because because of the belief that there is no trade-off between schedule and production, only between schedule and cost. Our analysis provides evidence to the contrary leading us to conclude that the order of priority should be reversed. We go beyond this observation and provide the reader with insights into how the unintended consequences of certain project drivers can be incorporated into more realistic economic models.

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Emerging standards and guidelines in the safety engineering field call for the application of safety assessment techniques throughout the development cycle of systems. Since much early work on design projects falls within the discipline of systems engineering, questions arise about the applicability of safety assessment techniques to system architectural descriptions and about the role of such analyses. A safety assessment technique applicable to system architectures is proposed, based on the classic concept of interfaces and derived from the HAZOP techique widely used in the process industries. The role of the technique in the wider integration of safety and design processes is discussed. A prototype tool to support the analysis is described and a trial of its use in an industrial application is reported. A concluding discussion considers the integration of safety and design processes.

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