Airlines carry passengers to their destinations on flights that cross oceans, deserts, mountain ranges and cities. Airlines operate a wide variety of aircraft; employ scores of pilots, flight attendants, ticket agents and dispatchers; and implement comprehensive safety programs. Airlines require physical resources to operate successfully and meet safety and profitability goals.


Since without aircraft airlines could not function, airplanes constitute a major resource for any airline. Regional airlines, which ferry passengers from smaller airports to major hubs, have an average fleet size of 30 to 50 planes. Major airlines have fleet sizes of more than 100 planes. In addition to their primary purpose of transportation, airplanes are used as marketing tools. Airlines sell the newness of their fleet, or "fleet age," as well as the aircraft size and creature comforts. Additionally, airlines market the recognizability of their aircraft, such as in the case of Delta Airlines and their Boeing 747s.


Airlines own hangars, which are large structures designed to house airplanes. Airlines use hangars as places to perform maintenance and store aircraft. Hangars very widely in size and shape based on which type of aircraft they hold. Airlines often have hangars at their hubs or focus airports. Hangars are very expensive to construct. According to Reed Construction Data, the average cost of an aircraft hangar was almost $2 million, as of 2008.


Airlines use computers and computer networks for ticket processing, dispatch, flight planning, crew scheduling and accounting. Computer systems for airlines perform a diversity of functions, including weather tracking and seating calculation. For this reason, airlines often install proprietary software on their computers. According to Computer Weekly, airlines spent an average of 1.8 percent of their budget on information technology in 2010.