- Sopra Steria is taking part in the European A4CLIMATE project dedicated to reducing the climate impact of aviation.
- The project is based on 400 test flights to better assess the non-CO₂ effects associated with contrails.
- Sopra Steria is developing the digital interfaces to visualise the climate impact and the costs of mitigation measures in real time.
Paris, 08 December 2025 - Sopra Steria, a major player in the Tech sector, is taking part in the European A4CLIMATE project alongside scientific and industrial bodies to improve the measurement and reduction of climate effects associated with flight operations, particularly those linked to contrails.
Contrails, produced by certain high-altitude flights, are a growing climate issue. Although temporary, when they form persistent clouds they can generate a warming effect comparable to that caused by all the CO₂ accumulated since the beginnings of aviation. The European Union has mandated the reporting of these non-CO₂ effects for international flights by 2028.
Funded by the Horizon Europe programme and coordinated by the German Aerospace Centre (DLR), the A4CLIMATE project brings together 17 partners from research, aeronautics, digital and innovation. The aim: to better understand, model and reduce these non-CO₂ effects by drawing on three complementary levers:
- optimising flight paths adapted to atmospheric conditions ;
- the study of modern engines with low soot emissions;
- analysing the contribution of alternative fuels.
A campaign of 400 demonstrator flights is underway to test routes designed to avoid areas prone to contrail formation. These flights are being evaluated using data from satellite observations, in-flight measurements and advanced atmospheric modelling.
In this context, Sopra Steria is developing software interfaces that enable the predictability of contrails, their level of uncertainty, their estimated climatic impact and the costs associated with the various mitigation measures to be displayed in real time. Developed on the basis of the real needs of airlines, manufacturers and navigation services, these solutions facilitate operational decision-making by integrating the project's scientific advances, notably on sustainable fuels (SAF), low-soot emission engines and climate-optimised trajectories. Sopra Steria is also developing representative use cases and leading the assessment of associated operational costs, in order to accelerate the adoption of these non-CO₂ strategies by the entire airline industry.