Labor is the main cost of the airline industry. Fuel comes in second, with commissions to travel agents coming in third. Most of the operating costs are fixed. https://people.hofstra.edu/geotrans/eng/ch3en/conc3en/airlinecosts.html http://www.investopedia.com/features/industryhandbook/airline.asp http://www.investopedia.com/features/industryhandbook/airline.asp