Competition in airline management is strengthening and increasing globally. Aircraft maintenance costs have an important place in this sense. Aircraft maintenance has a direct effect on the airline's ability to keep airplanes constantly in the air. Aircraft maintenance is done in a timely and complete manner, the airline's profit-loss balance affects. The main purpose of aircraft maintenance is to produce safer and more secure maintenance service. This service turns into a sales and marketing service by the airline. The purpose of this study is to investigate the maintenance costs of commercial passenger aircraft over a period of 10 years. The goal of this study is to investigate the maintenance costs aircraft fleet-based profitability with maintenance costs and all other costs. In the intention of the study, it enables the airline company to make profit-loss analysis on the basis of aircraft type. In addition to this, it shows the cost per hour to the airline company on the basis of aircraft type and the cost per seat. This will help the airline to make the right decision when buying an aircraft on a aircraft type basis, thus providing opportunity for the business by adding the option to compare all costs with past and future value
