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In more than 100 years of aviation, significant progress has been made in flight control systems. The aircrafts that have entered service for the past ten years tend towards power-by-wire flight control with electrical actuators. The purpose of this study is to analyse the effects of electrical actuation on power consumption, weight and fuel consumption on a commercial transport aircraft.

The Airbus A321-200 aircraft was chosen as a case study for analysing the effects of electrical actuation on the flight control actuation system (FCAS) architecture, and Pacelab SysArc software was used for design, modelling and analysis. As alternatives to the existing system, hybrid and all-electric models are built to a set of design guidelines with certain limitations.

Compared to the existing FCAS architecture model, 80 kg weight savings in the hybrid FCAS architecture model and 171 kg weight savings in the all-electric FCAS architecture model were observed. In terms of fuel consumption, it has been observed that there is 0.25% fuel savings in the hybrid FCAS architecture model, and 0.48% fuel savings in the all-electric FCAS architecture model compared to the existing FCAS architecture model at 3200 NM.

In line with the data obtained from this study, it is predicted that electrical actuation is more preferable in aircraft, considering its positive effects on weight and fuel consumption.

In this study, three different models were created: the existing FCAS architecture of a commercial transport aircraft, the hybrid FCAS architecture and the all-electric FCAS architecture. Hybrid and all-electric models are built according to a set of design guidelines, with certain limitations. Then, similar flight missions consisting of the same flight conditions are defined to analyse the effects of power consumption, weight, and fuel consumption comparatively.

The purpose of this paper is to investigate how the new theory on the general systemic yoyos can be plausibly employed to provide novel explanations for some of the well‐known laboratory experiments of physics and how a different theory that is more refined than the currently accepted theories can be established for illustrating phenomena that have not been completely explainable by using the traditional theories.

The general field structures of systemic yoyos, combined with some of the well‐known laboratory observation of physics, are employed as the basic methodology for the current paper.

Owing to the co‐existence of magnetic fields and ring‐shaped negative electric fields, all possible ways for an electromagneton to be fired into a stable, uniform‐intensity magnetic field are investigated. How such an electromagneton could be traveling under the mutual influence of the fields is described with details.

The value of this paper lies on the fact that it points out a brand new and practically applicable theory for looking at some of the well‐recorded phenomena of electromagnetism.

THE electric current is often compared, especially in “ popular ” works, to the flow of water in a pipe. This conception holds good in certain respects, but is definitely misleading in many ways. The ground engineer who wishes to obtain the “ X ” licence for electrical equipment need not, it is true, make such a close study of the fundamentals of electricity and magnetism as the electrical engineer or science degree student would have to do. Nevertheless, in order to understand the operation and maintenance of electrical apparatus, however simple, some theoretical knowledge is necessary. In electrical work, the beginner is confronted with one special difficulty—the absence of moving parts—and this difficulty seems to be most formidable to men who have been accustomed in their daily work to think in terms of crank‐shafts, gear‐wheels, cams, valves, push‐rods and all the other apparatus of mechanical engineering. To put the situation into a phrase, the beginner wants to “ see the wheels go round,” and is naturally somewhat baffled when he discovers that there are no wheels to go round. Some imagination is, therefore, necessary in studying electrical phenomena, and the student, particularly the engine fitter, must school himself to avoid the futile applica‐tion of well‐absorbed mechanical principles to apparatus in which they have no application.

The purpose of this paper is to analyze the electric propulsion use in civil aviation and propose a framework for certification of electric propulsion subsystems. Although electric propulsion architectures are discussed as key technology for the future of aviation, the industry standards as well as regulations fail to cover the application in full extent, specifically for commercial large airplanes. This paper proposes an approach for the analyses of reliability and certification of the new-generation propulsion system by pointing out the “common structure” among the possible architectures.

The research process used in this paper consists of following steps: the challenges of the hybrid-electric propulsion is listed, the architectures of the hybrid-electric applications in the literature are identified, the differences of the hybrid architectures from the present applications by means of application and standardization are discovered, the architectures are analyzed and the two main subsystems are defined – the present combustion system and the common unit, which is a similar structure used in all-electric aircraft. For this purpose, the standards used for design basis and certification of the present propulsion system and their relationship with the subsystems of the architectures have been analyzed. The procedure for the reliability assessment of the system is given, a framework for the safety assessment and the certification of the propulsion systems is proposed to make it easier and without sacrificing the already accumulated experience. This study shows that by using the common unit, the present certification framework can be used, by focusing on the reliability of the common unit and its integration with the rest of the architecture.

A specific definition of common unit is proposed, to point out the difference in certification efforts of hybrid-electric propulsion architectures. Yet, there is no data available for propulsion-level airborne battery and electrical systems to assess the reliability. Thus, dividing the propulsion system into two main systems and providing a model for certification of the common unit sub-system would be beneficial for easy deployment of the hybrid architectures both for design and for certification. In this paper, it is proposed that by using this common unit, the present certification framework can be used as it is, by focusing on the reliability of the common unit and its integration with the rest of the architecture.

The aircraft certification regulations act in two ways: they provide a starting point for new design projects, and they are a basis for certification of the final system. This study aims to draw focus on certification issues on the new-generation hybrid-electric propulsion systems. With the introduction of hybrid-electric propulsion for large aircraft, the present standards (CS-25, CS-E, CS-P, CS-Battery and CS-APU) create an obstacle for further progress as their borders get into each other. Instead of developing a new set of standard(s), this paper proposes a new approach by dividing the propulsion system into two subsystems.

This research proposes a definition of “common unit” for simplification of the hybrid-electric propulsion architectures for large civil aircraft. The common unit consists of both battery and electrical components and their reliability shall be considered for hybrid-electric propulsion.

The purpose of this article is to provide an outline of the challenges of thermal management for more-electric, hybrid-electric and all-electric aircraft, and to notionally discuss potential solutions.

A code algorithm was developed to facilitate architecture-level analysis of the coupled relationship between the propulsion system, the thermal management system, and the takeoff gross weight of aircraft with advanced propulsion systems.

A variety of coupled relationships between the propulsion and thermal management systems are identified, and their impact on the conceptual design choices for electric aircraft are discussed qualitatively.

This conceptual article merely illuminates some driving factors associated with thermal management. The software is still in its adolescence and is experiencing ongoing development.

Thermal regulation in electric aircraft is shown to be a topic that should be addressed in tandem with propulsion system architecture definition and component selection. High-power electronics are expected to emit an immense amount of heat, and the common avenues of heat dissipation could substantially impact the aircraft’s weight, drag and performance. Conversely, strategic management of this waste heat could support subsystems or even produce additional thrust.

This paper aims to direct the attention of researchers and designers in the field of hybrid- or all-electric aircraft design toward the challenges and potential benefits of thermal management.

This paper describes a novel conceptual design software and discusses its logic flow and implications.

This paper aims to assess the impact of electrifying the environmental control system (ECS) and ice protection system (IPS), the primary pneumatic system consumers in a conventional commercial transport aircraft, on aircraft weight, range, and fuel consumption.

The case study was carried out on Airbus A321-200 aircraft. Design, modelling and analysis processes were carried out on Pacelab SysArc software. Conventional and electrical ECS and IPS architectures were modelled and analysed considering different temperature profiles.

The simulation results have shown that the aircraft model with ±270 VDC ECS and IPS architecture is lighter, has a more extended range and has less relative fuel consumption. In addition, the simulation results showed that the maximum range and relative fuel economy of all three aircraft models increased slightly as the temperature increased.

Considering the findings in this paper, it is seen that the electrification of the conventional pneumatic system in aircraft has positive contributions in terms of weight, power consumption and fuel consumption.

The positive contributions in terms of weight, power consumption and fuel consumption in aircraft will be direct environmental and economic contributions.

Apart from the conventional ECS and IPS of the aircraft, two electrical architectures, 230 VAC and ±270 VDC, were modelled and analysed. To see the effects of the three models created in different temperature profiles, analyses were done for cold day, ISA standard day and hot day temperature profiles.

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IN this paper an attempt is mads to give some guidance as to what is needed for a modern aircraft electrical installation. The subject is extremely wide, and the electrical installation designer must have knowledge, not only of the methods of installing cables and equipment, but of the electrical requirements of the aircraft, the means of obtaining the power, and of controlling and distributing the energy to the best possible advantage. He must also know the needs peculiar to airborne conditions, the way to obtain a clear and precise presentation for operation and servicing, the proper source of the varied materials and equipment, and be capable of the design of items which are not otherwise obtainable. He must be able to direct his staff so that instructions are issued in the form of drawings which are as concise and as simple as possible.

The electric vehicle has been viewed as a technological solution to the dual plagues of dwindling fossil fuel supplies and pollutant emissions from gasoline powered vehicles. Futurists see a world where most personal transportation is electrically powered with energy supplied by tomorrow's power plants. In that future world, automobile power sources — representing millions of uncontrollable sources of pollution and energy waste — are consolidated into fewer, manageable, generators in fixed locations. With fixed and relatively few sources of pollution, resources can be better focused to provide clean, inexpensive energy for transportation. Many people share this vision of the future but few have been able to see how it can be brought into existence. Initial attempts have focused on legislation to stimulate the development of this market. As with any new technology, the electric vehicle field has developed its own terminology. For purposes of clarity throughout mis paper please bear in mind the following definitions.

In chemical plants, corrosion is present to some extent in practically all electrical installations. Some of this corrosion is of a limited nature and relatively harmless. In other cases a more suitable material or a better appreciation of design factors would avoid severe cases which call for costly shutdowns. Numerous metals and alloys are available for electrical installations; all have advantages and disadvantages. This information, together with pertinent design factors, is the key to trouble‐free electrical units.