Impact of Electric Taxi Systems on Airport Apron Operations and Gate Congestion

Abstract

Growth in air traffic demand and increasing attention for environmental impact of the air travel industry and airports has spurred the innovation of the Electric Taxi System (ETS). The ETS incorporates an electric motor in the main or nose landing gear of an aircraft, powered by the auxiliary power unit (APU) of the aircraft. The system allows the aircraft to maneuver and taxi without the use of its main engines or a tow truck. Thereby, the ETS reduces fuel usage and the environmental impact during the taxi phase of flights. Additionally, the system aims to increase the gate pushback efficiency. The ETS eliminates the need for a tow truck during the pushback process as it allows for autonomous pushbacks. The studies performed on existing ETSs (the EGTS and theWheelTug systems) indicate that time can be saved with autonomous pushbacks using the ETS. KLM Royal Dutch Airlines and Amsterdam Airport Schiphol (AAS) have instigated research to investigate the impact and potential benefits of the implementation of the ETS. This Msc. thesis research work continues the exploration of the ETS’s impact at AAS by posing the following research question: What opportunities does the ETS offer for gate capacity and buffer utilization optimization, and what is the value of the impact of the ETS on apron operations at Amsterdam Airport Schiphol? Thus, the research attempts to draw light on the value of the ETS for operations in the apron environment. With increasing air traffic demand, the gate capacity at Schiphol Airport is nearing its maximum during the airport’s peak hours. Therefore, the potential gate capacity enhancement procedures enabled by the ETS are explored in detail in this research. Additionally, the value of the ETS for the overall apron environment is investigated. The reduction in the need for tow trucks due to the ETS implementation also provides benefits for the apron environment. The ETS presents the possibility for of two gate usage optimization concepts to be implemented more widely,namely; the dispatch towing concept and the pit stop concept. The gate planningmodels designed in this research explore the potential of the implementation of the pit stop and dispatch towing concepts at AAS. Initially, a gate planning model is designed to graphically present the narrow body gate and buffer plan in gantt chart format. In doing so the gate and buffer planning schedule for the busiest day at AAS in 2014 is visualized. The pit stop and dispatch towing concepts are then applied to the schedule where possible. From the visualization of the gate plans with and without the ETS enabled concepts, it can be concluded that the pit stop concept increases gate capacity at AAS by approximately six additionally aircraft on the busiest day at the airport in 2014. Furthermore, the dipatch towing concept increases gate planning efficiency and reduces ground arrival delays for six arriving aircraft on the busiest day at the airport in 2014. The gate planning model is subsequently expanded in order to explore the effect of increased traffic and delays on the gate planning at AAS, and the usage of pit stops and dispatch towing to help increase gate capacity and solve delay conflicts, respectively. From the extended model it becomes apparent that should the number of peak hour flights at AAS increase by 10%, and average of 25% of the additional flights can be scheduled at a gate using the pit stop concept. Should the number of peak hour flights double, an average of 8.8% of the additional peak hour flights (corresponding to 12 flights) can be scheduled using the pit stop concept. Furthermore, the model shows that, between 10% and 12% of the ground delays caused by delayed peak hour flights at the gates can be solved through the implementation of dispatch towing. This results in an average of 17.2minutes saved for nearly 50% of the arriving delayed flights. The gate planning models have indicated the potential of the pit stop and dispatch towing concepts enabled by the ETS for gate planning efficiency and capacity at AAS. However, the implementation of the ETS influences many key performance indicators (KPIs) of the apron area. In order to explore the value of the ETS on the apron area, a value model is developed. The value model is based on the value operations methodology (VOM). The value model qualitative assessment indicates that the ETS can enhance the safety, capacity, and efficiency of the airport apron environment, while reducing the costs and environmental impact of the apron area operations. The results of the models and the research performed can be further analyzed and developed by KLM and AAS in order to assist in the development of electric taxi systems and, eventually, enhance their competitive position within the aviation industry.