The number of flights performed globally by the airline industry has increased steadily since the early 2000s and reached 38.9 million in 2019. However, due to the coronavirus pandemic, the number of flights dropped to 18.3 million in 2020. The flight volume increased again in the following years and was forecasted to reach 38.7 million in 2024. The global airline industry The number of flights performed increased year-on-year continuously to transport both passengers and freight. The industry’s recent growth can be attributed to a combination of increasing living standards and decreasing costs of air travel. While North American and European airlines currently dominate in terms of both revenue and passengers flown, it is predicted that future growth will be highest in markets of Asia.

In 2023, the estimated number of scheduled passengers boarded by the global airline industry amounted to approximately 4.5 billion people. This represents a significant increase compared to the previous year since the pandemic started and the positive trend was forecast to continue in 2024, with the scheduled passenger volume reaching just below five billion travelers. Airline passenger traffic The number of scheduled passengers handled by the global airline industry has increased in all but one of the last decade. Scheduled passengers refer to the number of passengers who have booked a flight with a commercial airline. Excluded are passengers on charter flights, whereby an entire plane is booked by a private group. In 2023, the Asia Pacific region had the highest share of airline passenger traffic, accounting for one third of the global total.

As a result of the continued annual growth in global air traffic passenger demand, the number of airplanes that were involved in accidents is on the increase. Although the United States is ranked among the 20 countries with the highest quality of air infrastructure, the U.S. reports the highest number of civil airliner accidents worldwide. 2020 was the year with more plane crashes victims, despite fewer flights The number of people killed in accidents involving large commercial aircraft has risen globally in 2020, even though the number of commercial flights performed last year dropped by 57 percent to 16.4 million. More than half of the total number of deaths were recorded in January 2020, when an Ukrainian plane was shot down in Iranian airspace, a tragedy that killed 176 people. The second fatal incident took place in May, when a Pakistani airliner crashed, killing 97 people. Changes in aviation safety In terms of fatal accidents, it seems that aviation safety experienced some decline on a couple of parameters. For example, there were 0.37 jet hull losses per one million flights in 2016. In 2017, passenger flights recorded the safest year in world history, with only 0.11 jet hull losses per one million flights. In 2020, the region with the highest hull loss rate was the Commonwealth of Independent States. These figures do not take into account accidents involving military, training, private, cargo and helicopter flights.

For the purposes of this paper, the National Airspace System (NAS) encompasses the operations of all aircraft which are subject to air traffic control procedures. The NAS is a highly complex dynamic system that is sensitive to aeronautical decision-making and risk management skills. In order to ensure a healthy system with safe flights a systematic approach to anomaly detection is very important when evaluating a given set of circumstances and for determination of the best possible course of action. Given the fact that the NAS is a vast and loosely integrated network of systems, it requires improved safety assurance capabilities to maintain an extremely low accident rate under increasingly dense operating conditions. Data mining based tools and techniques are required to support and aid operators’ (such as pilots, management, or policy makers) overall decision-making capacity. Within the NAS, the ability to analyze fleetwide aircraft data autonomously is still considered a significantly challenging task. For our purposes a fleet is defined as a group of aircraft sharing generally compatible parameter lists. Here, in this effort, we aim at developing a system level analysis scheme. In this paper we address the capability for detection of fleetwide anomalies as they occur, which itself is an important initiative toward the safety of the real-world flight operations. The flight data recorders archive millions of data points with valuable information on flights everyday. The operational parameters consist of both continuous and discrete (binary & categorical) data from several critical subsystems and numerous complex procedures. In this paper, we discuss a system level anomaly detection approach based on the theory of kernel learning to detect potential safety anomalies in a very large data base of commercial aircraft. We also demonstrate that the proposed approach uncovers some operationally significant events due to environmental, mechanical, and human factors issues in high dimensional, multivariate Flight Operations Quality Assurance (FOQA) data. We present the results of our detection algorithms on real FOQA data from a regional carrier.

In 2021, due to the coronavirus pandemic, only 13.8 billion gallons of fuel were consumed by U.S. airlines, compared to a high of 18.43 billion gallons in 2007. While the consumption of airline fuel in the United States has increased in recent years, it is yet to surpass the levels seen prior to the 2008 recession. Commercial airlines The above figures include all commercial air carriers based in the U.S. who carry cargo and/or passengers on domestic or international flights, and with annual revenue of over 20 million U.S. dollars. Excluded is airline fuel used for military or private flights. Given that the U.S. has the largest business and military aircraft fleets in the world, if included the figures would be appreciably higher. Overall growth in commercial aviation Given the commercial aviation market in the U.S. has experienced strong growth since 2009, with revenue figures and passenger traffic well above pre-recession levels, the fact that fuel consumption is currently lower than in 2007 may appear curious. The likely explanation is that the cost of airline fuel reached record levels around 2012, forcing airlines to find ways to decrease fuel consumption wherever possible.