Overview of Aviation Sector

Analysis scope and assumptions

Historical air traffic data in this section comes from Eurostat and EUROCONTROL, whose 20-year STATFOR traffic forecast provided the future traffic scenarios representing ‘high’, ‘base’ (most likely) and ‘low’ growth rates. The coverage is all flights from or to airports in the European Union (EU) and European Free Trade Association (EFTA). For more details on models, analysis methods, forecasts, supporting data sources and assumptions used in this section, please refer to Appendix C.

Air traffic

Recent strong growth, but flight counts still just below previous peak

In 2017, the number of flights in Europe was 1% below the all-time high reached in 2008. With the economic crisis, 2009 saw the biggest annual fall in flights of recent decades. The recovery in 2011 was temporary, but since 2014 a sustained return to growth is observed. In recent years, growth in low-cost flights has continued, while since 2015 the number of traditional scheduled flights has also increased (Figure 1.1 and Figure 1.2).

Passenger numbers have grown even faster, and are 50% higher in 2017 than 2005. This is partially due to a gradual shift towards flying further in larger aircraft with the average distance flown up 16% since 2005. Other contributions come from an increase in load factors (the fraction of seats that are occupied) from 70.2% to 80.3%, and the use of lighter and slimmer seats so that more passengers can be accommodated on the same aircraft. All of the above have resulted in a reduction in fuel burn per passenger kilometre flown (see emissions section).

The total cargo tonnage on all-cargo flights and in the belly hold of passenger flights went up by 55% from 2005 to 2017. However, the number of all-cargo flights decreased by 2% over the same period, indicating a shift towards belly cargo. In addition, smaller all-cargo aircraft with a take-off weight less than 50 tonnes had one of the sharpest reductions in number of flights over that period, indicating a shift to larger all-cargo aircraft.

Under the most-likely future scenario, hereafter referred to as the ‘base’ forecast, the total number of fl hts using EU28+EFTA airports is expected to reach 13.6 million in 2040, compared to 9.6 million in 2017 (Figure 1.3). This represents an average annual growth rate of 1.5% over this period. Although the forecast has been updated since the previous report, actual traffic growth has followed the base forecast, which explains why the 2035 figure remains unchanged.

Low-cost airlines now provide the majority of the scheduled network

From 2005 to 2017, the number of scheduled flights increased by 14%, whereas the number of city pairs with scheduled flights most weeks of the year increased by 43% from 6,000 to 8,600 (Figure 1.4). This is due to airline operators reducing the number of city pairs with high-frequency connecting flights, with the median number of flights each way decreasing from 4.2 per week to 3.2 per week. The traditional scheduled carriers have also reduced the number of city pairs that they serve infrequently (less than 3 times per week), although this was compensated elsewhere by low-cost carriers adding new connections on other city pairs. Indeed, the low-cost carriers now serve more city-pairs than the traditional scheduled airlines.

More city pairs in the network means a greater dispersion of local impacts such as noise. The reduction in high-frequency connections is linked to the increase in aircraft size, and the fact that traditional carriers have reduced their short-haul, intra EU28-EFTA connections rather than their long-haul. This will also have been influenced by competition from road and the high-speed rail network that continues to expand within Europe.

European fleet is young, but ageing slowly

Every year, new state-of-the-art aircraft join the European fleet to accommodate growth and replace old aircraft that are approaching the end of their operational life. Figure 1.5 shows the evolution of the average aircraft age per flight in Europe over time. Following the economic downturn in 2008, retirement of aircraft jumped to over 6% of the fleet in 2008 and 2009 from less than 3% between 2004 and 2007, and low cost carriers had a rapid expansion. This resulted in a reduction in the average aircraft age per flight.

The average aircraft age remained stable for a period, but has increased from 10.3 years in 2014 to 10.8 years in 2017. This increase in average age has been limited, despite a return to growth, by low-cost and traditional scheduled carriers investing in new aircraft such as the A320neo and B737 MAX families. The non-scheduled charter fleet has aged most rapidly, reflecting the decline of this segment and the switch to scheduled operations. The rapid expansion of business aviation up to 2008 was accompanied by the entry into service of new aircraft, but business aviation declined sharply with the economic downturn, which led to more frequent use of the existing aircraft and a gradual ageing in the fleet. The average age of aircraft used for all-cargo operations (i.e. not counting the passenger flights that often carry cargo too) is the highest of all, now reaching 21 years in 2017. It should be noted that new aircraft represent significant costs for operators, and a sufficient operational lifetime is required to ensure a return on their investment.

The daily distribution of flights remains stable

The annual share of flights in the day, evening and night time periods at EU28+EFTA airports has not changed significantly between 2005 and 2017, with 72% of departures and landings occurring between 07:00 and 19:00 local time, 19% between 19:00 and 23:00 and 9% between 23:00 and 07:00. Consequently, the total number of night time departures and landings follows the same trend as the total traffic, and has been increasing since 2013. The situation varies between airports, with some increasing their number of night flights and some decreasing.


The main pollutants emitted by aircraft engines in operations are carbon dioxide (CO2), nitrogen oxides (NOX), sulphur oxides (SOX), unburnt hydrocarbons (HC), carbon monoxide (CO), particulate matter (PM) and soot (Figure 1.8). This section provides trends in full-flight emissions of all flights departing from EU28 and EFTA airports.

CO2 and NOX emissions are continuing to grow

According to the data reported by Members States to the United Nations Framework Convention on Climate Change (UNFCCC), the CO2 emissions of all flights departing from EU28 and EFTA increased from 88 to 171 million tonnes (+95%) between 1990 and 2016 (Figure 1.9). In comparison, CO2 emissions estimated with the IMPACT model reached 163 million tonnes (Mt) in 2017, which is 16% more than 2005 and 10% more than 2014. Over the same period, the average fuel burn per passenger kilometre flown for passenger aircraft, excluding business aviation, went down by 24%. This has reduced at an average rate of 2.8% per annum between 2014 and 2017. However, this efficiency gain was not sufficient to counterbalance the increase in CO2 emitted due to the growth in the number of flights, aircraft size and flown distance. Future CO2 emissions under the base traffic forecast and advanced technology scenario are expected to increase by a further 21% to reach 198 Mt in 2040. The annual purchase of allowances by aircraft operators under the EU Emissions Trading System (ETS) since 2013 resulted in a reduction of 27 Mt of net CO2 emissions in 2017, which should rise to about 32 Mt by 2020.

NOX emissions have followed a steeper upwards trend than CO2 in recent years (Figure 1.10). They increased from 313 to 700 thousand tonnes between 1990 and 2016 according to the Convention on Long-Range Transboundary Air Pollution (CLRTAP) data from the UN Economic Commission for Europe, and by 25% between 2005 and 2017 according to estimates from the IMPACT model. Unlike the CO2 trend, current predictions indicate that the advanced engine NOX technology scenario could lead to a downward trend after 2030. However, NOx emissions would still reach around 1 million tonnes in 2040 under the base traffic forecast (+45% compared to 2005).

Aviation emissions in context
In 2016, aviation was accountable for 3.6% of the total EU28 greenhouse gas emissions and for 13.4% of the emissions from transport, making aviation the second most important source of transport GHG emissions after road traffic [17]. Greenhouse gas emissions from aviation in the EU have more than doubled since 1990, when it accounted for 1.4% of total emissions. As emissions from non-transport sources decline, the emissions from aviation become increasingly significant [10]. European aviation represented 20% of global aviation’s CO2 emissions in 2015. Aviation is also an important source of air pollutants, especially of nitrogen oxides (NOX) and particulate matter (PM). In 2015, it accounted for 14% of all EU transport NOX emissions, and for 7% of the total EU NOX emissions. In absolute terms, NOx emissions from aviation have doubled since 1990, and their relative share has quadrupled, as other economic sectors have achieved significant reductions. The carbon monoxide (CO) and oxides of sulphur (SOX) emissions from aviation have also gone up since 1990, while these emissions from most other transport modes have fallen [18].

It should be noted that the aviation sector is not fully comparable to other sectors of the economy, as emissions reductions can be more difficult to achieve in aviation. This is partially due to the relatively long lifespan of aircraft, which could remain in operation for 25 years or more. Cap-and-trade systems, as well as offsetting schemes, allow to compensate emissions from aviation through reductions achieved more easily in other sectors. However, aviation will need to deliver more in-sector emissions reductions.


Due to fleet renewal, emissions of HC, CO and PM have been relatively stable between 2005 and 2014. However, PM emissions are expected to increase over the next twenty years if engine technology remains as it is today (Table 1.3).

Combining indicators

Figure 1.11 presents the relative evolution of key air traffic and environmental indicators since 2005. This shows an increase in economic and connectivity benefits from aviation (measured in passenger kilometres flown) with a lower rate of increase in environmental impacts.

Stakeholder actions

Industry goals and actions on climate change

In 2008 the global stakeholder associations of the aviation industry (Airports Council International, Civil Air Navigation Services Organization, International Air Transport Association and International Coordinating Council of Aerospace Industries Associations), under the umbrella of the Air Transport Action Group, committed to addressing the global challenge of climate change and adopted a set of ambitious targets to mitigate CO2 emissions from air transport:

  • A cap on net aviation CO2 emissions from 2020 (carbon-neutral growth)
  • A reduction in net aviation CO2 emissions of 50% by 2050, relative to 2005 levels
  • An average improvement in fuel efficiency (CO2 per Revenue Tonne Kilometre) of 1.5% per year from 2009 to 2020 (Figure 1.12).

To achieve these targets, all stakeholders agreed to work closely together along a four-pillar strategy:

  • Improved technology, including the deployment of sustainable low-carbon fuels
  • More efficient aircraft operations
  • Infrastructure improvements, including modernized air traffic management systems
  • A single global market-based measure, to fill the remaining emissions gap.