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The purpose of this paper is to present the development of an optimal design framework for high altitude long endurance solar unmanned aerial vehicle. The proposed solar aircraft design framework provides a simple method to design solar aircraft for users of all levels of experience.

This design framework consists of algorithms and user interfaces for the design of experiments, optimization and mission analysis that includes aerodynamics, performance, solar energy, weight and flight distances.

The proposed sizing method produces the optimal solar aircraft that yields the minimum weight and satisfies the constraints such as the power balance, the night time energy balance and the lift coefficient limit.

The design conditions for the sizing process are given in terms of mission altitudes, flight dates, flight latitudes/longitudes and design factors for the aircraft configuration.

The framework environment is light and easily accessible as it is implemented using open programs without the use of any expensive commercial tools or in-house programs. In addition, this study presents a sizing method for solar aircraft as traditional sizing methods fail to reflect their unique features.

Solar aircraft can be used in place of a satellite and introduce many advantages. The solar aircraft is much cheaper than the conventional satellite, which costs approximately $200-300m. It operates at a closer altitude to the ground and allows for a better visual inspection. It also provides greater flexibility of missions and covers a wider range of applications.

This study presents the implementation of a function that yields optimized flight performance under the given mission conditions, such as climb, cruise and descent for a solar aircraft.

This paper aims to analyze the viability of a solar power system as a supplemental power source for commercial and business aircraft.

First, a model is established to estimate the potential available power from suitable aircraft surfaces for various meteorological conditions, ground and flight mission characteristics. A proposed aircraft system architecture and an associated parametric conceptual sizing model are presented. This supplemental solar power system sizing model is integrated into an aircraft multidisciplinary design optimization environment to evaluate the aircraft-level impact on mission fuel burn. A parametric study for a business jet aircraft is performed to analyze various solar cell types and power densities for converters. Trade-off studies are performed between efficiency and weight.

Considering today’s efficiency and power-to-weight ratio of the system components, overall fuel burn reduction can be achieved. Therefore, the technology development work can start now to target short to mid-term applications. In addition, promising system integration scenarios are identified, such as the use of solar power for autonomous operation of the air conditioning system on ground, which yield potential further benefit. In conclusion, a supplemental solar power system seems a promising candidate for more efficient aircraft operation.

The presented novel supplemental solar power system architecture concept and its foreseen aircraft integration show potential benefits for near term applications. The results show that the break even for this technology is already reached and therefore build the foundation to further investigate the technology integration challenges. Clear directions for future research and development are outlined enabling the advancement of the technology readiness level.

The aviation industry has started environment friendly and also conventional energy independent alternative energy dependent designs to reduce negative impacts on the nature and to maintain its future activities in a clear, renewable and sustainable way. One possible solution proposed is solar energy. Solar-powered aerial vehicles are seen as key solutions to reduce global warming effects. This study aims to simulate a mathematical model of a solar powered DC motor of an UAV on MATLAB/Simulink environment.

Maximum power point tracking (MPPT) is a critical term in photovoltaic (PV) array systems to provide the maximum power output to the related systems under certain conditions. In this paper, one of the popular MPPT techniques, “Incremental Conductance”, is simulated with solar-powered DC motor for an UAV design on MATLAB/Simulink.

The cascade structure (PV cell, MPPT, buck converter and DC motor models) is simulated and tested under various irradiance values, and results are compared to the DC motor technical data. As a result of that, mathematical model simulation results are overlapped with motor technical reference values in spite of irradiance changes.

It is suggested to be used in real time applications for future developments.

Different from other solar-powered DC motor literature works, a solar-powered DC motor mathematical model of an UAV is designed and simulated on MATLAB/Simulink environment. To adjust the maximum power output at the solar cell, incremental conductance MPPT technique is preferred and a buck converter structure is connected between MPPT and DC motor mathematical model. It is suggested to be used in solar-powered UAV designs for future developments.

The purpose of this paper is to examine the potential applications of stratospheric communication platforms (SCP), which have been recently introduced as an alternative for satellite communications.

Various applications, solutions and services are planned by using aircraft or airship SCP, which could be classified as digital narrowband or broadband, depending on the broadband required. The platforms as base stations can provide service for fixed and mobile applications, with commercial and military solutions. Subscribers will use uplink to the platform for transmitting and receiving information, where onboard SCP switching devices will downlink to the ground station and route traffic directly to other subscribers within the same platform coverage, to another platform via optical inter‐platform links, trough heterogeneous networks including satellite or to the terrestrial telecommunications network. Each SCP can deploy an antenna for large coverage area or a multibeam antenna capable of projecting numerous spot beams within its potential coverage area.

This paper outlines the findings of fixed and mobile applications, features, testing and some specific development programs of SCP using aircraft solutions, such as SkyTower and airship solutions, such as CRL/TAO/NAL.

Particular consideration is given to the use of SCP for delivery of future broadband, broadcast and multimedia wireless communications including research for new communication, navigation and surveillance (CNS) implications.

SCP will provide communication facilities that can exploit the best features for both terrestrial and satellite schemes.

Emerging solutions of voice, data and video over IP are offered by SCPs operating in the stratosphere at altitudes of up to 25 km.

To examine the role of new aeronautical technologies in improving commercial aviation’s environmental performance.

Reviews the environmental improvements that may be conferred through the adoption of alternative aviation fuels and new airframe, engine and navigation technologies.

Although aeronautical technologies have evolved considerably since the earliest days of powered flight, the aviation industry is now reaching a point of diminishing returns as growing global consumer demand for air transport outstrips incremental improvements in environmental efficiency. The chapter describes some of the technological interventions that are being pursued to improve aviation’s environmental performance and discusses the extent to which these innovations will help to deliver a more sustainable aviation industry.

The concept of solar‐powered flight has been considered so far in the future, that most people have not given it much attention. Not so with Larry Mauro, president of Ultralight Flying Machines, a 7 year old company that produces ultra‐light kits for gliders. For Larry, unusual ideas are a way of life.

This paper aims to describe the enhancement of the numerical method for conceptual phase of electric aircraft design.

The algorithm provides a balance between lift force and weight of the aircraft, together with drag and thrust force equilibrium, while modifying design variables. Wing geometry adjustment, mass correction and performance estimation are performed in an iterative process.

Aircraft numerical model, which is most often very simplified, has a number of new improvements. This enables to make more accurate analyses and to show relationships between design parameters and aircraft performance.

The presented approach can improve design results.

The new methodology, which includes enhanced numerical models for conceptual design, has not been presented before.

Purpose – To examine the relationship between aviation and climate change, and the international dimensions of air transport.

Methodology/approach – A review of aviation's impacts on the global climate, mitigation strategies to reduce this impact, and the possible consequences of climate change for commercial aviation.

Findings – Although a range of mitigation measures have been developed and implemented to reduce aircraft emissions in the short term, with some environmental benefit, there is a real need for the aviation sector to identify the possible impacts of climate change on air travel operations, both to aircraft in flight and to operations at airports. A further challenge will be to devise adaptation plans that will address the vulnerabilities and thus ensure safe aviation-related operations.

Social implications – The climate change impacts of aviation will adversely affect society. In addition, some individuals may have to reduce or stop flying as a result of increased taxes and legislation implemented in response to climate change.

Originality/value of paper – There is a novel focus on the adaptation challenges for the aviation industry in response to climate change.

The background of missile costs is discussed. Missiles are new and very costly. Developments in this field have been subjected to political vicissitudes which have often upset long‐term developments. Missile technology is on the frontier of science and there is no background of knowledge to draw on; much basic and expensive research is required. Missile engineering models are complex in detail and assembly, and therefore costly, and constant change occurs while making and testing the model. The complexity and functional requirements of missile parts are running a parallel race with the machines and processes being developed to fabricate the materials required. The usually small runs required in missile production again add to costs. Imposed on all these activities is the requirement that reliability of near 100 per cent is needed and in no case can reliability be allowed to be secondary to cost. The inflight life and shelf conditions for a missile are usually fairly well established and 100 per cent reliability for a short operating life with a long shelf life are the real requirements. There is a considerable tendency to overdesign for reliability. Some costly features of design such as finest finish, closest tolerances and highest strength are carried over by habit from aircraft design and are not always required in missiles. Having examined some causes of high costs, a programme for cost reduction is set out. Costs can be reduced by: (i) earlier freezing of designs making changes only in groups of several changes at wider intervals, (ii) making a more realistic approach to reliability designs, (iii) selecting tolerances in a more analytical manner according to individual needs, (iv) selecting materials on the basis of actual design requirements instead of using the very best materials available even when the short life makes them unnecessary, (v) avoiding tool‐room methods in production engineering, (vi) setting work standards on as many operations as possible and enforcing them to the greatest degree possible, (vii) selecting the best type of workers to make the transition from development models to production missiles as smooth as possible, and (viii) setting up rigid systems and parts designation procedures for handling production parts. Finally, methods of organizing research and development and production for bridging the gap between engineering design and production are proposed.