With the increasing coverage of the OpenSky, flight data gathered from the network of receivers has become a primary source of open data for aviation research. This year marks ten years of OpenSky. In this report, we employ a year's worth of OpenSky data to analyze the formation of contrails and study the potential mitigation with altitude diversions. Persistent contrails, often formed under humid atmospheric conditions, significantly trap outgoing terrestrial radiation. More insights into contrails are essential for studying aviation climate impact. We estimated the potential formation of persistent contrails based on the numerical weather assimilation data. An efficient approach is employed to fuse meteorology data in our analysis, which allows the fast evaluation of these contrail conditions at a very large scale. We designed a simple yet effective algorithm for flight with persistent contrails to study the shortest altitude diversion that would have prevented the contrail formations. We have estimated that between 5 % and 9 % of total flight distances each month could have formed persistent contrails. Furthermore, altitude diversions could have mitigated 70 % of these contrails.

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Established in 2013, The OpenSky Network, a crowdsourced network of ADS-B receivers, has consistently collected surveillance data from equipped aircraft and made it available for science. Coverage has steadily improved, boasting more than 6000 registered sensors worldwide today. This platform has aided numerous researchers in publishing studies across fields such as air traffic management, security, environment, and radio frequency interference. Following the 2020 mandate, most aircraft flying at high altitudes in Europe or Northern America are within range of one of the network’s ADS-B receivers. To complement existing research using OpenSky data, this paper focuses on lower altitude coverage, including light aircraft, general aviation, gliders, and ultralights, which are not required to carry ADS-B transponders. Instead, these often use, esp. in Europe, another traffic awareness and collision avoidance technology known as FLARM. The OpenSky Network has been gathering FLARM messages since 2018, and now enough data is available for a detailed analysis. The aim of this report is to present OpenSky’s FLARM data, explain the workings of the technology, and highlight potential uses of this data for future research.@en

Civil aviation contributes to rising global greenhouse gas emissions. Flights carried out by private and business jets are only a very small fraction of commercial passenger flights. However, these private flights are extremely environmentally inefficient and account for the most emissions per passenger in the aviation sector. While the commercial aviation sector has been under increased scrutiny by environmentalists for years, the footprint of private and business jets has entered the public eye only very recently. Social media provides new ways for sharing individual private flights, but the large-scale analysis of private jet flights and their emissions has been lacking until now. To better inform this discussion, we use open and large-scale flight data collected by the OpenSky Network over fours years and apply the OpenAP model in order to estimate the emissions of around 250 private jets. The total carbon emissions is found to be between 0.45 and 0.5 megatonnes. The yearly emissions from these selected jets is equivalent to 40,000 global inhabitant emissions. In our analysis, we provide further insight into private jet emissions and raise awareness about the emission inequalities in the current aviation system.

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The environmental impact of aviation has become the focus of increased concerns for policymakers around the world. The recent pandemic provided many interesting case studies on the impact of aviation on the environment. Following the initial COVID-19 containment measures and hard lockdowns, the sharp decrease in aircraft movements caused a measurably improved air quality worthy of further study.The OpenSky Network has acted as an important open data source for aviation research since 2013. In this paper, we analyze one year of fine-grained pre-COVID air traffic trajectories (comprising the entire year 2018) to estimate fuel consumption and pollutant emissions in the aviation industry. We compare this large-scale big data processing approach to a reduced model approach based solely on global commercial aircraft movement schedules collected from airlines and airports, aggregated by a commercial provider.Our study quantifies the impact of commercial aviation on global emissions. The numbers reveal that aviation's CO₂ emissions contribute to 2% of global emissions and that commercial aviation contribution remains a proxy for countries' wealth.

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The usage of large private and business jets, from those owned by Elon Musk to Kylie Jenner and Bernard Arnault, has recently attracted considerable attention in many countries. Enabled by open and crowdsourced aircraft tracking systems based on the automatic dependent surveillance–broadcast protocol, the aircraft and their owners have been scrutinized. While the underlying technology is not novel and its privacy issues have been discussed for years, the increased attention has led to the backlash against open tracking data and, consequently, a scramble to find possible solutions to hide private jets from the public eye. In this paper, we analyze two such methods, which have not yet been discussed previously in the literature: blocking requests to web tracking platforms and malicious editing of crowdsourced databases. We draw on data from the OpenSky Network and illustrate the futility of such approaches. Finally, we outline the type of stakeholders and aircraft deploying such methods, as well as demonstrate the level of environmental impact that might have otherwise been missed by the public.

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The year 2020 had been selected by EU and US regulators as the deadline for ADS-B compliant Mode S transponders, following various iterations of ADS-B and Mode S services. It will also be remembered as marking a profound change in civil aviation, when the global virus outbreak triggered an unprecedented slowdown in traffic and brought immense impact on the world economy. Fleets have been grounded and a great number of airplanes went into long-term storage due to travel restrictions. The OpenSky Network has been collecting valuable information regarding ADS-B compliance since 2017. It also acted as an important open data source for studying the aviation industry during these crisis times. In this paper, we analyze years of data collected by the OpenSky Network to provide an overview of the past and current situations in global air traffic with equipage updates, ADS-B implementation, Mode S interrogation practices, and fleet management by airlines.@en