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The demand for aviation has been steadily growing over the past few decades and will keep increasing in the future. The anticipated growth of traffic demand will cause the current airspace system, one that is already burdened by heavy operations and inefficient usage, to become even more congested than its current state. Because busy airports in the United States (U.S.) are becoming "bottlenecks" of the National Airspace System (NAS), it is of great importance to discover the most efficient means of using existing facilities to improve airport operations. This dissertation aims at designing an efficient airport surface operations management system that substantially contributes to the modernized NAS. First, a global comparison is conducted in the major airports within the U.S. and Europe in order to understand, compare, and explore the differences of surface operational efficiency in two systems. The comparison results are then presented for each airport pair with respect to various operational performance metrics, as well as airport capacity and different demand patterns. A detailed summary of the associated Air Traffic Management (ATM) strategies that are implemented in the U.S. and Europe can be found towards the end of this work. These strategies include: a single Air Navigation Service Provider (ANSP) in the U.S. and multiple ANSPs in Europe, airline scheduling and demand management differences, mixed usage of Instrument Flight Rule (IFR) and Visual Flight Rules (VFR) operations in the U.S., and varying gate management policies in two regions. For global comparison, unimpeded taxi time is the reference time used for measuring taxi performance. It has been noted that different methodologies are currently used to benchmark taxi times by the performance analysis groups in the U.S. and Europe, namely the Federal Aviation Authority (FAA) and EUROCONTROL. The consistent methodology to measure taxi efficiency is needed for the facilitation of global benchmarking. Therefore, after an in-depth factual comparison conducted for two varying methodologies, new methods to measure unimpeded taxi times are explored through various tools, including simulation software and projection of historical surveillance data. Moreover, a sophisticated statistical model is proposed as a state-of-the-art method to measure taxi efficiency while quantifying the impact of various factors to taxi inefficiency and supporting decision-makers with reliable measurements to improve the operational performance. Lastly, a real-time integrated airport surface operations management (RTI-ASOM) is presented to fulfil the third objective of this dissertation. It provides optimal trajectories for each aircraft between gates and runways with the objective of minimizing taxi delay and maximizing runway throughput. The use of Mixed Integer Linear Programming (MIP) formulation, Dynamic Programming for decomposition, and CPLEX optimization can permit the use of an efficient solution algorithm that can instantly solve the large-scale optimization problem. Examples are shown based on one-day track data at LaGuardia Airport (LGA) in New York City. In additional to base scenarios with historical data, simulation through MATLAB is constructed to provide further comparable scenarios, which can demonstrate a significant reduction of taxi times and improvement of runway utilization in RTI-ASOM. By strategically holding departures at gates, the application of RTI-ASOM also reduces excess delay on the airport surface, decreases fuel consumption at airports, and mitigates the consequential environmental impacts.

Over the last few years, the concept of civil Unmanned Aircraft System(s) (UAS) has been realised, with small UASs commonly used in industries such as law enforcement, agriculture and mapping. With increased development in other areas, such as logistics and advertisement, the size and range of civil UAS is likely to grow. Taken to the logical conclusion, it is likely that large scale UAS will be operating in civil airspace within the next decade. Although the airborne operations of civil UAS have already gathered much research attention, work is also required to determine how UAS will function when on the ground. Motivated by the assumption that large UAS will share ground facilities with manned aircraft, this thesis describes the preliminary development of an Automated Taxiing System(ATS) for UAS operating at civil aerodromes. To allow the ATS to function on the majority of UAS without the need for additional hardware, a visual sensing approach has been chosen, with the majority of work focusing on monocular image processing techniques. The purpose of the computer vision system is to provide direct sensor data which can be used to validate the vehicle s position, in addition to detecting potential collision risks. As aerospace regulations require the most robust and reliable algorithms for control, any methods which are not fully definable or explainable will not be suitable for real-world use. Therefore, non-deterministic methods and algorithms with hidden components (such as Artificial Neural Network (ANN)) have not been used. Instead, the visual sensing is achieved through a semantic segmentation, with separate segmentation and classification stages. Segmentation is performed using superpixels and reachability clustering to divide the image into single content clusters. Each cluster is then classified using multiple types of image data, probabilistically fused within a Bayesian network. The data set for testing has been provided by BAE Systems, allowing the system to be trained and tested on real-world aerodrome data. The system has demonstrated good performance on this limited dataset, accurately detecting both collision risks and terrain features for use in navigation.

This master thesis focuses on selected concepts of air transport, which have a potential of increasing the competitiveness of the sector. The main objective of this paper is to analyze and quantify the economic and environmental benefits of introducing the electronic taxiing concept and the Free Route Airspace concept under conditions of use in the Czech Republic. First two parts of the thesis describe the theoretical background and important international aviation organizations. The main part describes the concepts, the methodology of benefit analyzes and presents the results. The results of analyzes show the main benefits of introducing both the concepts and the economic impact in case of airlines in the form of cost savings associated with fuel and environmental impact in terms of reducing the amount of produced gas emissions.

This research introduces a high-performance electric taxiing system (ETS) as a modern solution to improve the on-ground operations of today’s aircraft, which are conventionally powered through the main engines. The presented ETS is propelled by electric motors, integrated into the main landing gear of a state-of-the-art midsize commercial aircraft, and powered by an additional not quantified electrical energy storage system. The proposed system can therefore operate autonomously from any aircraft-internal power source, i.e. Auxiliary Power Unit or equivalent. The main objective of this work is to assess the energy consumption of the introduced ETS while considering energy recuperation due to regenerative braking. The ETS powertrain is sized to match modern conventional taxi performances that were seen in 36 self-recorded takeoff- and landing taxi driving profiles. A custom ETS simulation model was developed and simulated across all available driving profiles to confirm the desired powertrain performance and to predict the system’s energy consumption. For the purpose of enhancing the validity of these energy consumption predictions, a suitable motor controller is then designed by the use of MATLAB Simulink. An easy-to-implement switch loss model was created to predict the ETS motor controller efficiency map. Finally, the former energy consumption predictions were revised for the implementation of the motor controller and an estimated traction motor efficiency map. The results exhibit that the revised ETS simulation model was capable of refining the energy consumption. It was found that the ETS will consume up to 9.89 kWh on average if the full potential of the traction motors energy recuperation capabilities are being used. The simulation outcomes further demonstrate that regenerative braking offers great potential in ETS applications since more than 14 % of required traction energy could be regenerated to yield the above mentioned average energy consumption. / Thesis / Master of Applied Science (MASc)

Driven by the gradually increasing electrification of the transportation industry, in particular the aviation sector, the future’s electrified aircraft requires not only an improvement of the flight operation, but also an enhancement of the movement on ground. One very promising concept to improve the taxiing operation is the integration of an electric propulsion system into the aircraft’s undercarriage, also called “Electric Taxiing”. This yields a decrease of the overall fuel consumption, reduction of emissions, and improvement of aircraft maneuverability to help reducing operating times on ground. In this thesis, the performance requirements for an electric taxiing system are investigated by using self-recorded real-life aircraft taxiing drive cycle data. Based upon the system requirements, the powertrain for the electric propulsion system is sized for a commercial midsize aircraft to achieve a similar driving performance to conventional taxiing maneuvers. The sized powertrain, including the determined electric motor characteristics, is evaluated using a developed simulation model which allows testing the proposed electric taxiing system given the attained drive cycles. For the electric machine which is implemented into the wheel of the aircraft’s main landing gear, an axial flux permanent magnet (AFPM) motor with segmented stator windings is selected due to its very compact structure while providing high torque capabilities. The AFPM motor is designed and evaluated by using analytical models and three-dimensional finite element analysis (3D FEA) to fulfill the specified motor characteristics required for the electric propulsion unit. Finally, suggestions for potential improvements and future work are discussed. / Thesis / Master of Applied Science (MASc)

Le projet d'avion électrique vise à remplacer les vecteurs énergétiques que sont les fluides hydrauliques et l'air comprimé par le courant électrique et d'obtenir en conséquence une diminution significative de la consommation en carburant Dans cette thèse, nous proposons deux solutions : la première dans un souci d'accroitre la disponibilités des actionneurs électriques et la seconde pour la traction au sol (taxiage d'avion). Dans la première étude, nous nous plaçons dans le cadre d'un actionneur pour lequel il est demandé une redondance électrique. Ceci peut être le cas d'un actionneur de mode « normal », redondé par un actionneur de type secours, mais où les fiabilités cumulées ne sont pas suffisantes, et où la partie électrique et la commande du système dit normal est redondé. Nous proposons une topologie de moteur synchrone à aimants permanents à bobinage à plots à deux étoiles découplées magnétiquement et à courant de court-circuit limité. Pour les machines à plots, nous avons établi un modèle semi analytique dans le but de prédire l'amplitude de la résultante des forces radiales agissant sur le rotor de cette machine en cas de fonctionnement en modes sain et dégradé. Nous avons établi le modèle de cette machine en vue de la commande et nous avons validé expérimentalement ce principe de conception sur un prototype dimensionné au laboratoire et réalisé par une société du groupe SAFRAN. Dans la seconde étude, nous avons investigué sur l'utilisation de moteurs multi-enroulements permettant de répondre au mieux à un cahier des charges exigeant pour une application de traction d'aéronefs: le « green taxiing ». Le principe est de permettre de faire varier le coefficient de couple d'un moteur de manière à optimiser la masse du moteur mais aussi les contraintes sur le convertisseur qui l'alimente permettant d'atteindre de larges plages de vitesse. Le modèle en vue de l'alimentation a été développé et validé par une comparaison à une résolution par éléments finis en magnétodynamique / The more electrical aircraft project aims at replacing most of current power generation sources by electrical ones. Consequently this replacement might generate a significant decrease of the fuel consumption. Through this thesis we determine two electrical solutions allowing on the one hand the increase of disponibility level of the actuators and on the other handthe aircraft taxiing by electrical means. We firstly focused on electrical actuators that require electrical redundancy. A first mean to achieve this redundancy is to use two actuators. Nevertheless this solution is not relevant under the reliability constraint because the global failure rate is increased. A double star permanent magnet synchronous motor with concentrated winding is proposed in which a special care was taken to the short circuit current limitation and the magnetic decoupling between the two star winding. We established a semi-analytic model for this kind of motors to predict the amplitude of the resultant of the radial forces acting on the rotor of the machine when operating under normal and faulty operation. We established the model of the machine in order to determine the command strategy. We experimentally validated all of the design principles mentioned above through a prototype designed in the laboratory and built by one of the SAFRAN group company. We secondly investigated on the way to apply the multi winding principles to a brand new project linked to the aircraft taxiing called “green taxiing”. The goal is to obtain a motor topology that allows operating on a wide speed range thanks to the command strategy and the change of its torque coefficient. We established the model of the machine and we compared the results given by this ingenious model to the results given by a finite element resolution using a transient magnetic application