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The purpose of this research is a preliminary selection of wing section, which would be the best suited for PW-100 – a MALE class UAV of 600 kg weight. PW-100 will be used as a testing platform in different institutions such as research institutes, industry research centers or universities of technology (phase 1) to enable the in-flight testing of various on-board systems (mobile radars, thermovision sensors, chemical sensors, antennas, teledetection systems and others). Untypical layout of PW-100 resulted from the plans of further development of this configuration for a military application.

Important role in the research described in this paper plays the selection of main wing section to fulfil the preliminary requirements regarding maximum lift coefficient, minimum drag, aerodynamic efficiency etc. Two different wing sections (R1082 and SA19) were tested in wind tunnel, both with flaps deflected at the range of 0°-30°. Experimental measurements were performed in the low turbulence wind tunnel with closed test section of 45 cm × 35 cm. Numerical simulations of the flow around the wing sections were performed using MSES code. Boundary conditions were assumed basing on the typical mission of PW-100 for flight altitude around 9,000 m, speed of 110 km/h what results in Re = 956,000.

Lift coefficients obtained from both experimental and numerical methods for single slatted airfoil SA19 are much higher than that of get for Ronch R1082 airfoil. PW-100 aircraft with SA19 airfoils will be able to be trimmed and fly at any altitude up to 9,000 m and with an arbitrary weight up to 600 kg. Aerodynamic characteristics of SA19 remain smoother and more predictable than that of R1082 airfoil. The very promising properties of SA19 airfoil are well known to the authors since the beginning of last decade when PW team worked together with IAI team on CAPECON project and now it was fully confirmed by this research.

It was confirmed that selection of the proper wing section for the special mission performed by UAV is of the highest importance decision to be taken at the preliminary design phase. Because there is a limited access to the base of technical parameters in many different UAVs classes and the classical analysis of trends cannot be fully applied, the wing section analysis, either experimental or numerical, must be performed. The situation is much worse than in the case of manned aircrafts because most of the modern UAVs are made of carbon or glass fiber, and therefore, there is no chance for analysis of trends.

This paper presents a very efficient method of assessing the influence of wing section on aircraft performance adopted for MALE class UAV, especially in an early stage of preliminary design process. The assessment is built mainly on three requirements: Maximum 2D lift coefficient for take-off configuration with flap deflected on 20 degrees should be greater than 2.4. Endurance factor CL1.5/CD for loitering conditions (Ma = 0.5 and CD0 = 0.008) should be greater than 110. The relative wing section thickness should be greater/equal than 19 per cent (it is required for high volume fuel tank located in the wings).

The purpose of this paper is to present an approach to a polar graph measurement by a flight testing technique and to propose a baseline research method for future tests of UAV polar graphs. The method presented can be used to demonstrate a conceptual and preliminary design process using a scaled, unmanned configuration. This shows how results of experimental flight tests using a scaled flying airframe may be described and analysed before manufacturing the full scale aircraft.

During the research, the flight tests were conducted for two aerodynamic configurations of a small UAV. This allowed the investigation of the influence of winglets and classic vertical stabilizers on the platform stability, performance and therefore polar graphs of a small unmanned aircraft.

A methodology of flight tests for the assessment of a small UAV’s polar graph has been proposed, performed and assessed. Two aerodynamic configurations were tested, and it was found that directional stability had a large influence on the UAV’s performance. A correlation between the speed and inclination of the altitude graph was found – i.e. the higher the flight speed, the steeper the altitude graph (higher descent speed, steeper flight path angle). This could be considered as a basic verification that the recorded data have a physical sense.

The polar graph and therefore glide ratio of the aircraft is a major factor for determining its performance and power required for flight. Using the right flight test procedure can speed-up the process of measuring glide ratio, making it easier, faster, robust, more effective and accurate in future research of novel, especially unorthodox configurations. This paper also can be useful for the proper selection of requirements and preliminary design parameters for making the design process more economically effective.

This paper presents a very efficient method of assessing the design parameters of UAVs, especially the polar graph, in an early stage of the design process. Aircraft designers and producers have been widely performing flight testing for years. However, these procedures and practical customs are usually not wide spread and very often are treated as the company’s “know how”. Results presented in this paper are original, relatively easily be repeated and checked. They may be used either by professionals, highly motivated individuals and representatives of small companies or also by ambitious amateurs.

Using unpublished time‐series data for three specific age/gender groups, we first determine the percentage of female employment to total employment for nine sectors of the U.S. economy. Second, we estimate the cyclical change in hours of employment for each age/gender group within each sector. Third, we estimate the cyclical behavior of the nominal wage for each sectoral gender group. The paper’s evidence does not support, in general, a more cyclical response of female hours worked in the service‐producing sectors that are dominated by women. We find partial evidence that hours worked by men are more cyclical compared with hours worked by women in the male‐dominated goods‐producing sectors. Given the evidence of no pronounced difference in the cyclical behavior of hours and wages for men and women, the business cycle is gender‐neutral.That is, the elastic female labor supply is washed out over the business cycle across major sectors of the U.S. Economy. Observational evidence suggests supply‐side and structural factors in the economy have attenuated the business cycle, especially in the service‐producing sectors.

A survey was carried out of users, and potential users of the BBC Scotland Information Research Library services. Two postal questionnaires were sent out in the summer of 1995 to more than 100 individuals and organisations in Scotland. Based upon a 50% response rate, various conclusions could be drawn. Internal respondents were very satisfied with the services they currently received, but were, unsurprisingly, unwilling to pay significant sums to receive the services. There is some potential interest from outside the BBC in the Library's Events Guide. The exercise was undertaken both to assess the potential market for the Events Guide and to raise awareness generally of the Library's services. The results provide valuable pointers to how the BBC Scotland library services can develop, and, in time, the survey may turn out to have been a valuable marketing tool in its own right.

We show how to quickly estimate spatial probit models for large data sets using maximum likelihood. Like Beron and Vijverberg (2004), we use the GHK (Geweke-Hajivassiliou-Keane) algorithm to perform maximum simulated likelihood estimation. However, using the GHK for large sample sizes has been viewed as extremely difficult (Wang, Iglesias, & Wooldridge, 2013). Nonetheless, for sparse covariance and precision matrices often encountered in spatial settings, the GHK can be applied to very large sample sizes as its operation counts and memory requirements increase almost linearly with n when using sparse matrix techniques.

This chapter identifies that distributed leadership is about sharing power for political pluralism. Distributed leadership has a comprehensive commitment to bringing different groups with different interests, different languages and dialects, different knowledge bases, different metaphysical knowledge and different religions, or no religion, together through provisional agreement on key principals of political pluralism. Marginalised groups may not feel like they belong and may be vulnerable to ideologies that give them a sense of being disconnected from community. Such a position stands as a barrier to political pluralism and shared world views. The situation might be ignored in schools because developing political liberalism through participatory, evidence-informed leadership that is logical, moral and ethical requires time, and agents need to be prepared for such identity work. However, the problem cannot be ignored if community members seek to belong with risky gangs, and are vulnerable to radicalisation, which is very dangerous for them and for their communities. Empowering others may be achieved by developing their capability to ask good questions, and apply collaborative critical thinking for solving social and personal problems. Such empowerment requires shifts from hierarchical teaching of standardised knowledge that is right or wrong to doing the right thing as mature citizens in becoming. The chapter also identifies that it cannot be assumed that leaders are willing or able to distribute leadership, or that doing so would be a panacea for navigating the turbulence faced by their schools to empower societal innovators for equity and renewal. Rather, we concur with Leithwood et al. (2008) who advocate for a thoughtful and purposeful approach to developing leadership for school improvement.