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The purpose of this paper is to present a definition of modern configuration for a medium-altitude long-endurance unmanned aerial vehicle (MALE UAV) and its on-board systems to obtain a suitable basis for future definitions such as a possible logistic support configuration first hypothesis.

Starting from high-level requirements, both the UAV conceptual design and on-board systems preliminary design have been carried out through proprietary tools. Then, some peculiarities from previous studies, such as systems advanced UAV alternative energy, have been maintained and confirmed (diesel propulsion and energy storage system).

The improvement of a component of an aircraft can play a relevant role in the whole system. In the paper, it is considered how a concept of MALE UAV can evolve (this topic is considered by the authors since many years) by incorporating advanced on-board systems concepts.

The numerical results promote and support the use of advanced on-board system solutions and architectures to improve the effectiveness, efficiency and performance of MALE UAVs.

Usually, conceptual and preliminary design phases analyze in-depth the aerodynamic and structural solutions and aircraft performance. In this study, the authors aim to focus on the advanced on-board systems for MALE UAVs. This kind of aircraft is not yet a mature concept, with very few operating machines and many projects in the development phase.

This paper aims to present the main results achieved in the frame of the TIVANO national-funded project which may anticipate, in a stepped approach, the evolution and the design of the enabling technologies needed for a hybrid/electric medium altitude long endurance (MALE) unmanned aerial vehicle (UAV) to perform persistent intelligence surveillance reconnaissance (ISR) military operations.

Different architectures of hybrid-propulsion system are analyzed pointing out their operating modes to select the more suitable architecture for the reference aircraft. The selected architecture is further analyzed together with its electric power plant branch focusing on electric system architecture and the selected electric machine. A final comparison between the hybrid and standard propulsion is given at aircraft level.

The use of hybrid propulsion may lead to a reduction of the total aircraft mass and an increase in safety level. However, this result comes together with a reduced performance in climb phase.

This study can be used as a reference for similar studies and it provides a detailed description of propulsion operating modes, power management, electric system and machine architecture.

This study presents a novel application of hybrid propulsion focusing on a three tons class MALE UAV for ISR missions. It provides new operating modes of the propulsion system and a detailed electric architecture of its powertrain branch and machine. Some considerations on noise emissions and infra-red traceability of this propulsion, at aircraft level.

The purpose of this paper is to perform a technical and economical analysis on the conversion of a regional turboprop platform for Airborne Early Warning and Control (AEW&C) missions by supposing installation of supplementary diesel turbo‐charged engines.

The problem has been approached by considering all issues related to conversion to AEW&C platform. Class II methods have been used for weight and drag estimations. Flight performances have been evaluated by using standard equations of flight mechanics. Costs have been evaluated by using a model developed by the authors.

As far as performances are concerned, it is possible to increase aircraft service ceiling of about 4,400 ft by installing auxiliary diesel engines in separate wing‐nacelles. The low specific fuel consumption (SFC) of diesel engines balances the reduction of mission endurance caused by the aerodynamic drag increment (i.e. additional drag of AEW radar antenna and new nacelles). The proposed solution is shown to have the best Effectiveness‐Cost performance in comparison with other AEW&C aircraft‐systems.

To convert regional turboprops to AEW&C platform by employing turbocharged diesel engines could be an interesting future perspective for aerospace companies interested in creating a new AEW&C market segment.

The proposed solution gives the possibility to reduce operating costs in the AEW&C mission field. The issue is actual due to typical high operating costs of AEW&C missions.

The purpose of this paper is to describe the tool and procedure developed in order to design the control laws of several UAV (Unmanned Aerial Vehicle) sub‐systems. The authors designed and developed the logics governing: landing gear, nose wheel steering, wheel braking, and fuel system.

This procedure is based on a general purpose, object‐oriented, simulation tool. The development method used is based on three‐steps. The main structure of the control laws is defined through flow charts; then the logics are ported to ANSI‐C programming language; finally the code is implemented inside the status model. The status model is a Matlab‐Simulink model, which uses an embedded Matlab‐function to model the FCC (Flight Control Computer). The core block is linked with the components, but cannot access their internal model. Interfaces between FCCs and system components in the model reflect real system ones.

The user verifies systems' reactions in real time, through the status model. Using block‐oriented approach, development of the control laws and integration of several systems is faster.

The tool aims to test and validate the control laws dynamically, helping specialists to find out odd logics or undesired responses, during the pre‐design.

The development team can test and verify the control laws in various failure scenarios. This tool allows more reliable and effective logics to be produced, which can be directly used on the system.