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This is the second of two companion papers presenting the results of research into a contra‐rotating propeller designed to drive a super manoeuvrable micro air vehicle (MAV) and is devoted to the experimental results. The first paper presented the design process and numerical analyses.

Most of experiments were conducted in the wind tunnel. Both contra‐rotating and conventional propellers were tested. The test procedures and equipment are described first. The attention is focused on the design of an aerodynamic balance used in the experiment. Then, the measurement error is discussed, followed by presentation of the wind tunnel results. Finally, an initial flight test of the MAV equipped with contra‐rotating propeller is briefly described.

Wind tunnel experiment results fall between theoretical results presented in the first part of the paper. The application of contra‐rotating propeller allowed to develop the propulsion system with zero torque. Moreover, the efficiency achieved appeared to be a few percent greater than that for a standard conventional propulsion system. The concept was finally proved during the first test flight of the new MAV.

The propeller was designed for a fixed wing aeroplane, not for helicopter rotor. Therefore, only conditions characteristic for fixed wing aeroplane flight are tested.

The designed contra‐rotating propeller can be used in fixed wing aeroplane if torque equal to zero is required.

Original design of the balance is described for the first time, as well as test procedures applied in this experiment. Most of wind tunnel test results are also new and never published before.

The purpose of this paper is to describe factors associated with incarceration as well as the association between recent incarceration and HIV-related sexual risk behaviors, access to insurance, healthcare utilization (emergency department (ED) and hospital use), antiretroviral therapy (ART) prescription, and viral suppression.

Using 2009-2010 data from a cross-sectional, nationally representative three-stage sample of HIV-infected adults receiving care in the USA, the authors assessed the demographic characteristics, healthcare utilization, and clinical outcomes of HIV-infected persons who had been recently incarcerated (detention for>24 hours in the past year) using bivariate analyses. The authors used multivariable logistic regression to examine associations of recent incarceration with insurance status as well as clinical and behavioral outcomes.

An estimated 22,949 (95 percent confidence interval (CI) 19,062-26,836) or 5.4 percent (CI: 4.7-6.1) of all HIV-infected persons receiving care were recently incarcerated. Factors associated with recent incarceration were age <50 years, being a smoker, having high school diploma or less, being homeless, income at or below the poverty guidelines, having a geometric mean of CD4 count <500 cells/μL, and using drugs in the past 12 months. Results from multivariable modeling indicated that incarcerated persons were more likely to use ED services, and to have been hospitalized, and less likely to have achieved viral suppression.

Recent incarceration independently predicted worse health outcomes and greater use of emergency services among HIV-infected adults currently in HIV care. Options to improve the HIV continuum of care, including pre-enrollment for healthcare coverage and discharge planning, may lead to better health outcomes for HIV-infected inmates post-release.