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An instrumentation system for in-situ measurement of the inner-outer pressure differential at the upper and lower surfaces of dynamically inflatable wings is designed and tested, revealing important insights into the aerodynamic characteristics of inflatable airfoils. Wind tunnel tests demonstrated full capability of low-pressure differential readings in the range of 1.0–120 Pa, covering speeds from 3 to 10 m/s at angles of attack from −20 to +25°. Readings were stable, presenting coefficients of variation from 2% to 7% over the operational flight envelope. The experimental data confirmed the occurrence of a bottom leading-edge recirculation bubble, linked to the low Reynolds regime and the presence of an air intake. It supported the proposition of a novel approach to aerodynamic characterization based on local pressure differentials, which takes in account the confined airflow structure and provides lift forces estimations compatible with practical observation. The results were also compatible with data previously obtained following different strategies and were shown to be effective for parameterizing the inflation and stall phenomena. Overall, the instrumentation may be applied straightforwardly as a flight-test equipment, and it can be further converted into collapse alert and prevention systems.

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This paper offers a contribution responding to the challenge of making efficiency reports from public organizations intelligible to society. The proposed methodology is based on a combination of Activity Based Costing System and Free Disposable Hull performance analysis. Per-unit cost of outcomes are derived from annual budget using cost drivers defined in terms of internal resources distribution and public services demand. Efficiency is, then, evaluated based on benchmarked key performance indicators (KPI). A simulated application using limited data available for the Brazilian Civil Aviation Agency (ANAC) illustrates how the strategy could increase data meaningfulness from a citizens' perspective.