An in-depth analysis of factors influencing pilots' selection between auxiliary power units and external ground power units in the aviation industry, and tactical recommendations for optimized usage in a medium size Lebanese airline with a fleet of airbus A320

Abstract

In the aviation industry, auxiliary power units (APUs) and ground power units (GPUs) are essential in airplane's ground powering. APUs are onboard power sources, while GPUs are external power sources. The main difference between them lies in their location and design. APUs are jet engines mounted on the aircraft, producing electricity and air whenever needed in the air or on the ground (Skybrary, 2023) [1]. Meanwhile, the GPUs are offboard power sources and power the plane without needing an APU. They are diesel engines or inverters connected to the airport power grid. Based on this key difference, this paper investigates the advantages of using GPUs over APUs in an airline based in Lebanon and flying to Europe, the Middle East, and the Gulf region. Furthermore, the APU runs on jet fuel and typically represents about 2 to 2.5% of an airline’s fuel consumption, whereas worldwide, the aviation industry emits 2.4% of total CO2 emissions (Overton, 2022)[2]. Therefore, the focus is on optimizing costs, emissions, and noise. By analyzing different alternatives and scenarios, this study aims to enable informed decision-making at each destination, considering local regulations, weather data, equipment prices, fuel prices, and maintenance costs. This paper includes a detailed questionnaire completed by flight crew, engineers, and ground personnel to uncover valuable insights. A knowledge gap was found regarding the differences between APUs and GPUs and the associated costs. Furthermore, the research reveals inefficiencies in APU usage, leading to unnecessary fuel consumption. Additionally, cost savings were observed by using the GPU instead of APU, with some destinations offering the GPU free of charge during the initial hours or as part of prepaid bundles. On top of that, by turning off the APU, the study shows potential improvements in employee satisfaction, comfort, communication, concentration, and safety. In parallel, the study highlights the importance of training employees to understand the differences in prices and impacts between APUs and GPUs, enabling clear accountability and adherence to defined policies. This thesis unites all the latter factors into one calculation matrix by following the Multi-Attribute Utility Theory (MAUT). In addition, it suggests a framework to assist airlines in selecting the best power source alternative. In conclusion, this comprehensive analysis bridges the gap in the statistical cost analysis and the gap in decision-making. Integrating numbers, perspectives, safety considerations, and organizational behavior provides airlines with a well-rounded framework for corporate-informed decision-making. The research's goal is to facilitate the optimization of operational efficiency, environmental sustainability, and the well-being of employees, ultimately shaping the future of aviation and benefiting both the industry and the environment.