International Journal of Sustainable Aviation (14 papers in press)
The role of integration in achieving sustainable benefits from airline alliances
by Gamze Orhan, Deniz Taşcı
Abstract: Air transport is one of the industries where strategic alliances are most common. While alliance strategies by airlines are widespread, the performance and sustainability of alliances is currently in debate. However, the importance of the level of integration for the benefits from mergers and alliances in the literature is an important topic discussed. In this study, we relate the sustainability of alliances to the benefits gained from that cooperation and aimed to demonstrate the importance of the level of integration on the alliance benefits in the airline industry. To achieve this aim, after a comprehensive literature, we conducted a research on three global airline alliance members. The study comprises 26 international airlines who are members of one of global airline alliances Star, SkyTeam and Oneworld. The results suggest that there is a significant and positive relationship between level of integration of airlines to the global alliance and the alliance benefits gained from the alliance membership.
Keywords: strategic alliances; strategic management; sustainable benefits; integration level; airline alliances.
Robust planning the landing process of unmanned aerial vehicles
by Nguyen Dinh Dung, Joszef Rohacs
Abstract: Unmanned aerial vehicle (UAV) is a particular robotics type that has been studied by scientists in the world. Currently, the study of flying robots in complex environments is relatively well developed and has many achievements. However, the fact that the landing process of UAVs in complex or unknown environments is a significant challenge for scientists. In this paper, the problem that how to determine the desired landing orbit will be solved. The approach and landing process might be constructed from the straight lines and orbit curves. This study indicates that the UAV has four landing trajectories because the UAV can turn left or right to reach the left or right circle in the landing process. The methodology for calculating these landing trajectories will be shown in this paper, which is calculated based on solving aircraft equations of motion and analytical method. The desired landing orbit is the shortest route selected from these trajectories. This paper also shows the methodologies to determine the landing routes that the UAV can be landing in any direction or given direction. The simulation results utilizing MATLAB software show that the calculated landing orbit is the shortest.
Keywords: unmanned aerial vehicle; landing trajectory; landing process; desired landing orbit.
Cultural and Political Attitudes Towards Paying to Support Airport Sustainability Projects
by Mattie Milner, Dylan Bush, Emily Anania, Taro Ito, Daniel Marte, Stephen Rice, Scott Winter
Abstract: The current research explores different factors affecting individuals support for airports implementing environmentally-friendly programs. Using social identity theory, the researchers manipulated participants identification with one of the two major political parties to explore the relationship between political affiliation and support for environmentally-friendly initiatives. Participants (recruited from the U.S. and India) were presented with a hypothetical scenario in which twelve different sustainable aviation projects would be implemented at their local airport. Implementation of these projects would include a $15 fee to their ticket price. Participants were then asked to indicate their support for the additional fee for each of the twelve programs. Results from this study indicate significant differences in acceptance of sustainable aviation programs based on a variety of political and cultural factors. In general, liberals/progressives and Indians were more willing to pay the additional fee, regardless of the type of program.
Keywords: sustainable aviation; social identity theory; political affiliation; cultural attitudes; environmental concern; support for sustainable projects.
Turbofan engine weight estimation for preliminary design
by Mustafa Karabacak, Onder Turan
Abstract: The aim of the study is to prepare weight estimation model of turbofan engines to help designer in the conceptual stages of modern turbofan design. To achieve this purpose, statistical data is used on yielding robust analytical expression and experiments are conducted to prepare model for turbofan engine weight estimation is not easy due to the high cost and insufficient technical facility. Turbofan engine classified into 5 categories (3 shaft turbofan engine, light weight 2 shaft turbofan engine , medium weight 2 shaft turbofan engine, high weight 2 shaft turbofan engine and 2 shaft geared turbofan engine) and turbofan engine weight model is developed for each category separately to increase model sensitivity. Model sensitivity is investigated for each category by error analysis to give idea about model reflection of real world to conceptual designer.
Keywords: turbofan engine weight; thrust to weight ratio; bypass ratio; aircraft.
A SIMPLISTIC FLIGHT MODEL FOR EXERGY EMBODIMENT OF COMPOSITE MATERIALS TOWARDS NEARLY-ZERO EXERGY AVIATION
by S.A.N. KILKIS, Siir KILKIS
Abstract: For airliners, weight is energy spending and money. The heavier a plane, the more fuel it has to carry for a given range that limits the range and lowers the fuel economy. This snowball effect is a major concern not only for the economic outlook of the airline industry but also for the future of sustainable aviation. The motivation of increasing fuel efficiency and improving the aerodynamic performance of new aircraft has led designers to move away from using metals in airframes. Aluminum has the highest embodied energy, exergy, and carbon dioxide emissions among all basic materials while carbon fiber composites have much higher energy and exergy embodiments. For this reason, a careful balance between the advantages of lighter aircraft during operation and the disadvantages of an aircraft with more embodiments must be considered. In this paper, a new model for the embodied exergy payback period is presented, which considers the exergy savings during acceleration and takeoff, climb, trim-level cruise, descent and thrust reversal in landing for each flight versus higher exergy embodiment of composites that are used during manufacturing when compared to metals. The research work has ramifications for determining the optimum balance of lightweight and conventional material usage, thus improving the economic and environmental performance of aircraft for decoupling sustainable aviation and carbon dioxide emissions. The research work concludes with a vision for nearly-zero exergy aviation that involves a complete set of measures for the airside and landside. Considering new metrics for fuel savings and CO2 emissions based on exergy, the use of composite materials in new aircraft requires support from air traffic optimization, jet fuel produced from renewable energy systems, nearly-zero exergy airport terminals, and sustainable taxiing solutions. The research work has the potential for supporting the Carbon Neutral Growth Strategy of the aviation sector.
Keywords: Exergy embodiment; CO2 embodiment; fuel economy; composite materials in aircrafts.
Effect of Different Weightage of Enova
by A.B.D. RAHIM ABU TALIB, Ibrahim Mohammed, Wahiyuddin Rujhan, Nadiir Bheekhun
Abstract: The study presents the use of the green coat of Enova
Keywords: Aluminium alloy; composite; Enova® IC3100; Flax fibre; ISO2685 standard.
Design of loosely-coupled INS/GPS integration system applied to Boeing-747 aircraft model
by Chingiz Hajiyev, Deniz Burak Kamiloğlu
Abstract: Inertial navigation systems (INSs) require some type of aiding and updating in the long term to remain valid. In many applications for purpose of INSs error compensation its integration by GPS is preferred. In this study, the Kalman filter-based loosely-coupled integrated INS/GPS is designed and investigated on the Boeing-747 aircraft model. The INS errors are modelled, estimated and compared with integrated navigation system errors which are position, velocity and attitude for each axis. The proposed integrated navigation system has high accuracy than stand-alone INS and it provides more reliable navigation information.
Keywords: integrated navigation system; inertial navigation system; INS; Kalman filter; GPS; loosely-coupled integrated INS/GPS.
Sustainable flight test project tools
by Darli Vieira, Paulo Quattrocchi
Abstract: One of the most important aspects of the development of a new aviation product is the testing and verification phase. This paper identifies procedures to optimise certification flight test campaigns as one troublesome and unpredictable aspect of aircraft development. Considering a large market historical sample from key aircraft manufacturers for the certification of their products, we conclude that a sustainable approach with flight hour reduction, selected engineering tools and management tools will result in a considerable reduction in fossil fuel expenses and overall product certification time and cost.
Keywords: management tools; flight tests; engineering tools; cost reduction; sustainability.
Environmental control system analysis to investigate the indoor air quality of an aircraft
by Cem Tahsin Yücer, Hakan Keskin
Abstract: Environmental control system (ECS) in aircraft provide comfortable environment for people and goods. The temperature, pressure and humidity are vital properties of indoor air in aircraft. In this study, the systems used for conditioning the indoor air of the aircraft are considered. The hot and pressurised air that came from the compressor of the engine is transferred to the cabin by changing some of its characteristics. Thus, the indoor air quality is controlled. This study analyses the ECS in aircraft. Some of these systems are cabin air conditioning, pressurisation, humidity control and temperature control. When investigating these systems, some important values were obtained for ensuring the comfort and safety in the aircraft. Fresh air renewal period, strength for the skin panel, humidity formed in the cabin and heating demand were found to be 443 s, 84.8 kN/m2, 0.6 g/kg and 106.2 kW, respectively.
Keywords: indoor air quality; aircraft environmental control systems; indoor air conditioning.
Perspectives for application of the internet of things and big data analytics on end of life aircraft treatment
by Samira Keivanpour, Daoud Ait Kadi
Abstract: Recycling and advanced management of the aircraft at the end of life (EoL) is a novel challenge in the aviation industry. The new paradigm of the internet of things (IoT), Industry 4.0 and big data analytics in the logistics and operation management have a considerable impact on the sustainability of EoL aircraft treatment. This paper aims to highlight the role of IoT and big data analytics in the future of EoL aircraft management based on the waste hierarchy approach. Strategy, architecture, and infrastructure of IoT enabled EoL treatment is proposed, and an empirical study based on secondary data is provided to show the application. This study confirms the merits of using IoT and big data analytics to improve EoL aircraft treatment process in sustainability and performance.
Keywords: end of life aircraft; internet of things; IoT; big data; waste hierarchy approach; data warehouses; online analytical process; OLAP; radio frequency identification; RFID; aviation industry; sustainability; dismantling.
Determining the mechanical properties of sandwich composite materials for aviation applications
by Berke Turkkal, Arda Can Cinkilic, Sule Kapkin
Abstract: Flexure testing is one of the earliest means of evaluating stiffness and strength. This test is suggested to use in determination of the facing properties of the resistant materials (Kuenzi, 1951). This study was carried out to perform bending test of sandwich constructions suitable for ASTM D7249/D7249M standards and to determine facing material properties of sandwich constructions through evaluating the experimental data. Performing and conducting of the test: this study was carried out with collaboration of the Istanbul University and Turkish Airlines Technic under privacy in order to determine the facing properties of the sandwich constructions and it includes experimental and numerical methods. The study was carried out based on accepted standards.
Keywords: ISSA; sandwich constructions; aviation; bending tests; A-basis values; long beam flexure.
Exploiting the synergy between aircraft architecture and electric power system in unmanned aerial vehicle through many-objective optimisation
by Teresa Donateo, Claudia Lucia De Pascalis, Antonio Ficarella
Abstract: This study addresses the preliminary design of a fixed-wing, tailsitter electric unmanned aerial vehicle (with vertical take-off and landing capability) by optimising the size of the powertrain components together with the main aircraft design specification. To this scope, different optimisation problems are considered, with two, three and four objective functions, respectively. The results of the optimisation are used not only to compare the performance of different optimisation algorithms when increasing the number of goals, but also to discuss the synergy between architecture and power systems optimisation.
Keywords: all electric aircraft; VTOL UAV; many-objective optimisation.
Research of the JET A-1 aircraft fuel electrification
by Igor L. Trofimov, Andrian A. Iavniuk, Marharyta M. Radomska
Abstract: The paper presents the study of aviation fuel JET A-1 electrification and substantiation of the possibility to use static electricity for power generation. The modern aircraft refuelling with high-performance pumps followed by the fine filtration is a stable source of static charges generation, which raises the need to combat them. The results of the experiments show the dependence between the parameters of static charge density and the flow, flow rate, flow rate gradient and length of the pipeline. The level of the tank filling has been also accounted as a special index. We have also developed the device and the method for obtaining high voltage power, which is based on the positive use of the static electricity charges derived from the static charge converter. The further research must cover the effect of fuels electrification on the change of their operational properties, with the subsequent possibility of their modification.
Keywords: aviation fuel; electrification; dielectric liquids; electric charges; filters; pipes; charge density; device.
Methodological proposal for the supply chain risk management within the aeronautical sector
by Miguel Suffo, Roberto C. Brome
Abstract: This works describes the agents involved in the supply chain of the aeronautical sector. These agents are in charge of receiving and processing truthful information that is subject to a series of risks. Within the paradigm of globalisation of markets, the aeronautics industries must face the risks derived from the decentralisation of their value processes. Even though this decentralisation is mainly aimed at reducing costs, it also generates uncertainty due to the introduction of suppliers in developing markets. We propose a methodology that helps identify and classify these risks and allows selecting and sizing the most appropriate strategy to deal with them. The most frequent reactions developed by the companies to manage the risks are explained through a real case study of the aeronautical sector. Finally, in only six months, the application of the methodology to the real aeronautical case has allowed the risk management department to reduce them by 35%.
Keywords: supply chain; risk management; aerospace.