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Clean Sky's mission centres around environment, competitiveness and mobility.

The Greening of Aviation

Air transport currently accounts for around 2% of the 36 billion tonnes of CO2 generated annually by human activities.

Each new generation of aircraft saves 15-20% in fuel and CO2 compared to the aircraft it replaces, but global demand continues to increase by more than 4% per annum (over 9,500 new aircraft have entered service since 2009), creating an estimated need for 40,000 new aircraft over the next 20 years. Market estimates predict the sector will continue growing along with the socio-economic drivers for better European and global air transport connectivity - while simultaneously mitigating aviation's environmental impact.

The aviation industry is characterised by long technological timescales: from the conception of new technologies to the end-of-life disposal of the last aircraft using such technologies, the cycle can last a century. This is attributable to technical complexity, safety pre-eminence bringing stringent certification rules, and extended timeframes for ROI.

The aircraft of 2050 are under development right now, with a long programme of ground and flying demonstrations before they are deemed fit to carry passengers across Europe and the world.

Even though air transport emissions are comparatively low, the aviation community is committed to reducing their environmental impact in light of increasing demand for extra passenger capacity. In 2001 the Advisory Council for Aeronautical Research in Europe (ACARE) defined stringent global targets to be achieved by aircraft technology maturing in 2020, compared with state-of-the-art technology of the year 2000:

  • reduce fuel consumption and CO2 emissions by 50% per passenger kilometre;
  • reduce NOx emissions by 80%;
  • reduce perceived noise by 50%;
  • make substantial progress in reducing the environmental impact of the manufacture, maintenance and disposal of aircraft and related products. Click here for more info.

Clean Sky’s own targets vary according to the commercial flying segment, but average a 25-30% emissions decrease compared to year 2000 figures. For instance, ACARE's target of 50% CO2 emissions reduction is expected to be contributed to at 40% by greener technologies (developed in Clean Sky and other national programmes) and at 10% by more efficient ATM (Air Traffic Management), the latter undertaken in the Clean Sky parallel programme carried out by the SESAR Joint Undertaking.

To ensure the success of Clean Sky's ambitious and multifaceted programme, a quality performance tool - the Technology Evaluator - has been developed to facilitate internal assessment of the potential of each individual technology at each step of its development.

The Technology Evaluator is a highly sophisticated computer model which forecasts the efficacy of sub-system and system technologies such as engines, the shaping of a wing, navigation systems and the reduction of noxious gases and noise.

Results achieved to date by Clean Sky are on-track to meet the original targets, and the deployment of Clean Sky technologies represents a major leap forward in meeting the overall environmental targets, contributing strongly to improving societal impact.



*Reduction percentages are compared to emissions and noise produced by an aircraft manufactured with year 2000 technology.


**The percentage value shows the reduction of the noise footprint in areas surrounding airports for same noise levels produced by currently operating fleets.


View Demonstrators in Action


The future: Clean Sky 2

Clean Sky 2 builds on the success of Clean Sky 1, integrating further breakthrough technologies at aircraft level and delivering in-flight demonstrations of innovative architectures and configurations, enabling changes in environmental and economic performance. Its technical programme is partly a continuation of Clean Sky 1 and partly a widening of initiatives, leading to novel technological solutions in specific commercial flying segments.

Beyond 2020, new efforts are needed to get within reach of the Flightpath 2050 targets of a 75% cut in CO2, a 90% reduction in NOx and a 65% reduction in noise. Clean Sky 2 is geared to that and is focused on achieving substantial results en route to these goals. Innovations from Clean Sky 2 will underpin advances in the next generation of aircraft by mastering technologies and improving risk-management processes in a timely manner, meeting the next market window replacing the current fleet.

Enhanced competitiveness

Aerospace is one of the top-ranking sectors of excellence of Europe. The European aeronautical industry leads, or co-leads, worldwide, with steady growth (contributing 4% of the EU's GDP in 2013) - growth that translates into over half a million jobs in the sector. That figure feeds into a broader eco-system of 8.1 million aviation-related jobs.

Clean Sky follows an industry-led approach, encompassing large aircraft manufacturers, engine and equipment manufacturers, all participating in this ‘joint’ initiative - ‘joint’ meaning not only with public institutions but also industrial stakeholders - that are sometimes market competitors. This has created a very wide and innovative eco-system across Europe, with more than 600 participating entities in 24 countries. 

View Clean Sky participants across Europe