In aviation, MRO typically involve routine checks and inspections to satisfy airworthiness requirements. The global market comprise of individual segments for aircraft engines, components, line, airframe and modifications. The largest of these segments is the engine segment. It accounted for around 40 percent of the global civil air transport MRO market in 2015 and is projected to reach a value of over 45 billion U.S. dollars by 2025. In that same year, global aircraft line maintenance is expected to reach a market size of around 17.9 billion U.S. dollars. Some of the major commercial aircraft engine manufacturers in the world include: General Electric Aviation, CFM International, as well as Rolls Royce. In 2016, General Electric generated revenue of about 26.3 billion U.S. dollars from the aviation sector alone.
The International Civil Aviation Organization (ICAO) sets the global regulatory standards that are implemented by either a national or regional regulatory body such as the Federal Aviation Administration (FAA) in the United States.