MIAMI – Planes or trains? That is the question that arises from Eurocontrol’s Think Paper #11 that informs, stimulates debate, and presents alternative solutions to a difficult choice regarding travel on short-medium distances.

Keeping in mind that climate change requires urgent action to curb its effects, the aviation industry is well aware of the need to “go green” by reducing and completely offsetting its carbon emissions by 2050, as required by the EU Green Deal. To reach this goal, one way that is being theorized is to replace some air routes with High-Speed Trains (HST) or even old-style Sleeper trains.

The Eurocontrol Think Paper goes into a deep examination of environmental, economic, and social issues that a shift from air to rail transport would have. The paper, by going through the latest information comparing air and rail sustainability, aims to assess if such a shift is a real option for Europe.

To achieve this goal, the paper identifies areas where, instead of exclusion, complementing factors between air and rail may exist. The paper seeks an answer to three main questions:

  1. What would be the impact of shifting from air to rail and how feasible is this shift?
  2. What are the trade-offs necessary to get the air-rail balance right?
  3. In which circumstances would air-rail complementarity work better?
Milan Malpensa Airport Photo: Alberto Cucini/Airways

Main Findings


  1. When travel distance is under a 500km (270nm) range, High-Speed Trains (HST) represent the best potential. However, this travel segment, representing 24.1% of European flights accounts for only 3.8% of air travel emissions. Another aspect is that, because of geographical constraints, not all emissions savings would be achieved. In the 500 to 1,000km (270 to 540nm) range, the HST would not be a valid substitute for air travel.
  2. Another important point consists in the time necessary to deploy new HST infrastructure, requiring on average from 18 to 26 years. By this time, around 2050, aircraft would be reaching the industry’s zero-emissions goal based on the widespread use of SAF (Sustainable Aviation Fuel) along with new technology-based propulsion systems. Alternative transport investments will have to be carefully balanced considering that benefits from aviation decarbonization would apply to all European distance ranges. HST would represent a valid solution only on short distances.
  3. Studies proposing an air to rail substitution do not take into account the environmental and economic impact that a vast expansion of HST networks would create, which would result in an uneven “playing-field assessment” due to the lack of data on the rail market and infrastructure. Additionally, the construction of 10,000km (5400nm) of new HST connections would not be sufficient to match the connectivity offered by air transport and would require an investment of US$300bn (€250bn). The massive expansion of HST lines would also have a great socioeconomic impact and biodiversity loss, and does not compare favorably with aviation requiring less new infrastructure.
  4. Another aspect is geographical. It is impossible for rail to substitute air travel in the case of islands or remote areas that face geographical barriers for which connectivity is vital for any economic existence.
  5. Finally, in dense metropolitan areas or where HST infrastructure is already well established, multimodal solutions, combining air and rail, represent an area where it is possible to optimize sustainability and improve connectivity. In this case, complementarity is a way towards meeting emission reductions goals by shifting from “plane vs train” to “plane and train” solutions.

The paper concludes that decarbonization is way more complex than the simple solution of shifting from air to rail when travel stands below the 500km (270nm) range, as this alternative would have a limited impact on the climate while generating negative drawbacks.

Complementarity and intermodality are the aspects to be capitalized on, and the paper recommends that “investments be balanced with a view to developing multimodal solutions.”

For more in deep information: Eurocontrol Think Paper #11


Featured image: Air France Airbus A318 F-GUGO. Photo: Alberto Cucini/Airways