A4Climate

Advancing Aeronautics and Aerosol Research to Accelerate Climate-Neutral Aviation

A4Climate is a European research project dedicated to reducing the climate impact of aviation by tackling one of its most uncertain and potent contributors: non-CO₂ effects, especially contrails. A4Climate is funded under the Horizon Europe programme. 

One part of A4Climate consists of extra flight hours (four research flights) during the upcoming HALO mission AEROCLOUD, scheduled for summer/fall 2027. AEROCLOUD (funded by DFG, DLR, and MPG) focuses on particle emissions from aircraft at cruise altitude and the influence of the emitted particle on contrail formation. A second part of our A4Climate activities includes ground based field measurements at Frankfurt Airport, with the objective to characterize lubrication oil emissions from in-use aircraft engines. This campaign, termed “A4CRAFT” was conducted from March 26 until May 13, 2026.