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The presented paper aims to describe the general idea, simulations and prototyping process of an assisting flight control system (FCS) for light sport aircraft (LSA). The proposed FCS framework is intended to simplify piloting, reduce pilot workload, and improve system's reliability and handling qualities of manual flying.

Assisting flight control strategy integrates mechanical and digital FCS into a synergic platform, combining the high reliability of mechanical controls with the computation and actuation power introduced through a single line digital FCS. Concepts drawn from classical control theory along with flight envelope protection algorithms have been used throughout the design of the flight control laws. A prototype of the assisting FCS has been subjected to validation trials during series of hardware-in-the-loop simulations.

Despite controversies between the pilots' perception of a modern aircraft and limitations imposed by the legacy airworthiness codes, it has been shown that a pilot assisting and workload reducing control system can be successfully implemented on board of a LSA while satisfying the expectations on a state-of-the-art equipment meeting required level of safety defined by the current legislation.

A transition between specific flight modes as well as nonlinearities in the FCS may lead to unfavorable and unpredictable forms of aircraft-pilot interactions. The number of accessible flight control modes should be therefore limited to the most significant ones.

Sport aircraft are mostly flown by a single pilot, who could benefit from the pilot assisting FCS as the system has the potential to supervise the aircraft's safe operation in various flight conditions.

Introducing an assisting FCS on board of a LSA through an innovative approach which utilizes hidden and unused resources of modern digital automatic FCSs while respecting the limitations imposed through the weight and cost sensitive nature of the LSA market.

The purpose of this paper is to present the research efforts of the Center of Aeronautical Studies of the Federal University of Minas Gerais – Brazil to develop a low‐cost flight test data acquisition system for light aircraft and unmanned aerial vehicles (UAEs).

The development of this system was based on a microcontroller, chosen in accordance with main requirements of light aircrafts flight tests. The system uses the microcontroller in order to communicate with different kinds of sensors, including a GPS, and organize this information to be sent to a PDA device, which is used to control the acquisition process and storage the data acquired. Details about the development of this system, including firmware algorithm and sensors development, are presented and discussed in the paper.

The paper presents example results obtained with this system in applications such as performance evaluation and stability and control derivatives estimation problems. Take into account all the aspects of the system and the quality of the results, the main conclusion is that this system can efficiently support the demands of the aerospace industry for light aircraft and UAEs development programs as well as the necessities of the research centers and universities developing aeronautical research and didactic programs.

Recently, results confirm the applicability of this system in order to perform flight tests of aircrafts in accordance with FAR‐Part 23 or CS‐VLA or Light Sport Aircrafts as required by FAA Order 8130.2F and ASTM Designation F2245‐04.

This paper presents details about the construction of a low‐cost data acquisition system for flight tests of light aircrafts. The main advantage of this system is the use of a PDA device in order to control and storage the acquisition, which reduce costs, weight and size of the system and permits its installation in light aircrafts or UAVs.

When comparing and contrasting different types of fixed-wing military aircraft on the basis of an energetic efficiency figure-of-merit, unmanned aerial vehicles (UAVs) dedicated to tactical medium-altitude long-endurance (MALE) operations appear to have significant potential when hybrid-electric propulsion and power systems (HEPPS) are implemented. Beginning with a baseline Eulair drone, this paper aims to examine the feasibility of retro-fitting with an Autarkic-Parallel-HEPPS architecture to enhance performance of the original single diesel engine.

In view of the low gravimetric specific energy performance attributes of batteries in the foreseeable future, the best approach was found to be one in which the Parallel-HEPPS architecture has the thermal engine augmented by an organic rankine cycle (ORC). For this study, with the outer mould lines fixed, the goal was to increase endurance without increasing the Eulair drone maximum take-off weight beyond an upper limit of +10%. The intent was to also retain take-off distance and climb performance or, where possible, improve upon these aspects. Therefore, as the focus of the work was on power scheduling, two primary control variables were identified as degree-of-hybridisation for useful power and cut-off altitude during the en route climb phase. Quasi-static methods were used for technical sub-space modelling, and these modules were linked into a constrained optimisation algorithm.

Results showed that an Autarkic-Parallel-HEPPS architecture comprising an ORC thermal energy recovery apparatus and high-end year-2020 battery, the endurance of the considered aircraft could be increased by 11%, i.e. a total of around 28 h, including de-icing system, in-flight recharge and emergency aircraft recovery capabilities. The same aircraft with the de-icing functionality removed resulted in a 20% increase in maximum endurance to 30 h.

Although the adoption of Series/Parallel-HEPPS only solutions do tend to generate questionable improvements in UAV operational performance, combinations of HEPPS with energy recovery machines that use, for example, an ORC, were found to have merit. Furthermore, such architectural solutions could also offer opportunity to facilitate additional functions like de-icing and emergency aircraft recovery during engine failure, which is either not available for UAVs today or prove to be prohibitive in terms of operational performance attributes when implemented using a conventional PPS approach.

This technical paper highlights a new degree of freedom in terms of power scheduling during climbing transversal flight operations. A control parameter of cut-off altitude for all types of HEPPS-based aircraft should be introduced into the technical decision-making/optimisation/analysis scheme and is seen to be a fundamental aspect when conducting trade-studies with respect to degree-of-hybridisation for useful power.

The purpose of this paper is to present a novel retractable main landing gear for a light amphibious airplane, while the design, synthesis and analysis are given in details for constructing the main landing gear.

The constraint three-position synthesis has given the correct path of all linkages that suitably fit the landing gear into the compartment. The additional lock-link is introduced into the design to ensure the securement of the mechanism while landing. Having the telescopic gas-oil shock strut as a core element to absorb the impact load, it enhances the ability and efficiency to withstand higher impact than others type of light amphibious airplane.

By kinematics bifurcation analysis, the optimized value of the unlock spring stiffness at 90 N/m can be found to tremendously reduce the extended-retracted linear actuator force from 500 N to 150 N at the beginning of the retraction sequence. This could limit the size and weight of the landing gear actuator of the light amphibious airplane.

The drop test of the landing gear to comply with the ASTM f-2245 (Standard Specification for Design and Performance of a Light Sport Airplane) reveals that the novel landing gear can withstand the impact load at the drop height determined by the standard. The maximum impact loading 4.8 G occurs at the drop height of 300 mm, and there is no sign of any detrimental or failure of the landing gear or the structure of the light amphibious airplane. The impact settling time response reaches the 2% of steady-state value in approximately 1.2 s that ensure the safety and stability of the amphibious airplane if it subjects to an accidentally hard landing.

This paper presents unique applications of a retractable main landing gear of a light amphibious airplane. The proposed landing gear functions properly and complies with the drop test standard, ensuring the safety and reliability of the airplane and exploiting the airworthiness certification process.

Europe has adopted the Flight Path 2050 (FP2050) challenge demanding that by 2050, 90 per cent of the travelers are able to reach door-to-door destinations in Europe within four hours. A hypothesis can be formulated that without the Small Air Transport (SAT) system, optimized for short distances and for multiple but narrow passenger flows, this challenge cannot be met.

This paper defines design goals and necessary research focused on small aircraft concepts, as a required condition to fulfil the FP2050 challenge “90 per cent d2d 4h”.

The new small aircraft concepts have been defined as SAT Aircraft Family Program. Three demonstrators with common modules could be proposed: two using the same turboprop engine (first, one engine, 9 passengers; second, two engines, 19 passengers) and third demonstrator could be with a diesel hybrid engine.

The SAT Aircraft Family Program depends on demand optimized for specific regional features (passenger flows, passenger time value spectrum and infrastructure) and a set of matured technologies as a result of Clean Sky 2 (CS2) devoted to SAT.

This practical implications consist of developing on SAT technologies in CS2, deploying the demonstrators by the small aviation industry and launching an SAT system pilot phase.

FP2050 has changed the approach to a citizen-oriented from an atomized technologies taxonomy-oriented one. The challenge “90 per cent d2d 4h” also covers the needs of remote regions. This niche could be filled by the SAT system using the small aircrafts family.

The paper value is in defining entry requirements, answering how to build the SAT Aircraft Family Program satisfying the FP2050 challenge “90 per cent d2d 4h”.