Launched in 2021 under the Horizon Europe framework, the Clean Aviation Joint Undertaking (CAJU) is the public-private partnership of the European Commission dedicated to climate-neutral aviation. It represents the evolution of the Clean Sky (2007–2017) and Clean Sky 2 (2014–2024) programmes, through which the European Union has provided more than 5 billion euros in funding for research and innovation in the aeronautics sector.

Clean Aviation aims to support the aviation sector in meeting the objectives of the EU Green Deal, adopted in 2020, and achieving climate neutrality by 2050. Building on the extensive experience gained from previous programmes, it promotes synergies and collaboration between partnerships focused on breakthrough technological initiatives that contribute to reducing noise pollution and CO₂ and NOx emissions.