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The purpose of this paper is to present the preliminary design of a medium altitude long endurance (MALE) unmanned aerial vehicle (UAV), focusing on the interaction between the aerodynamic and the structural design studies.

The classic layout theory was used, adjusted for the needs of unmanned aircraft, including aerodynamic calculations, presizing methods and CFD, to estimate key aerodynamic and stability coefficients. Considering the structural aspects, a combination of layout, finite element methods and custom parameterized design tools were used, allowing automatic reshapes of the skin and the internal structural parts, which are mainly made of composite materials. Interaction loops were defined between the aforementioned studies to optimize the performance of the aerial vehicle, maximize the aerodynamic efficiency and reduce the structural weight.

The complete design procedure of a UAV is shown, starting from the final stages of conceptual design, up to the point where the detail design and mechanical drawings initiated.

This paper presents a complete view of a design study of a MALE UAV, which was successfully constructed and flight-tested.

This study presents a complete, synergetic approach between the configuration layout, aerodynamic and structural aspects of a MALE UAV.

The purpose of this paper is to focus on the finite element (FE) analyses undertaken for aerodynamically and structurally optimized design of a modern, lightweight civil unmanned air vehicle (UAV) made fully of composite materials.

The FE method has been applied to design and calculate the safety factors of all structural elements of the UAV. Fully parameterized design tools have been developed in the preliminary design phase, allowing automatic reshapes of the skin and the internal structural parts, wherever needed, to achieve optimal structural design, from the point of view of lightweight and structural integrity. Monotonic and fatigue tests have been performed on material specimens with various thicknesses and fibre textures, to verify the material properties used for the FE analyses. The load assumptions were in accordance with the valid international standards.

The material tests confirmed the validity of the material properties used within the FE calculations. The calculated safety factors were acceptable for all structural elements and components of the UAV. As a result, a lightweight, structurally optimized design has been achieved, considering the international, standardized specifications assumptions and fulfilling the safety requirements.

Design engineers may use the outcomes of this work as a guide to achieve optimal lightweight structures ensuring its operational strength using composite, lightweight materials.

A new, structurally optimized, lightweight aircraft design has been developed, able to accommodate heavy electronic payloads while being able to fly for over ten hours without refuelling. This medium altitude long endurance airplane can overview forests, seas and human trafficking autonomously and economically.

The economic and social problems, including high unemployment, facing the Greek economy in recent years are substantial. The role of the agri-food sector and agriculture in dealing with unemployment is a concern. To support the agricultural economy, a Common Agricultural Policy (CAP) 2007–2014 was adopted and implemented in the EU Member States. However, boosting employment, in the industry itself and indirectly in the economy, has almost never been a key goal of any policy. The purpose of this paper is to examine the role of the CAP 2014–2020 in maintaining and enhancing employment and income distribution in the region of Central Macedonia.

The authors used the regional social accounting matrix (SAM), which examines the depiction of the interconnections between the sectors of economic activity and local economy (households, businesses, public) but also interconnections and transactions with the rest of the world. The SAM presents a more complete picture of the economic figures of the region, evaluating the interconnections of cross-sectoral relations and the implemented policies, both in the production sectors and in the regional society.

For the Central Macedonia region, the agricultural sector is a key player, holding a regulatory role for regional economic viability, and shows marked connections with the other industry branches of the region.

The new CAP 2014–2020 through Pillar 2–Rural Development may reinforce the new role of the industry in terms of the environment, integrated rural development and social structure of rural areas, ensuring coherence.