Safran has started ground tests of its Open Rotor demonstrator engine on a new test stand in Istres, southern France.  The company says the demonstrator — developed through Europe's Clean Sky research programme — is a strategic focus of its Research & Technology efforts, and a key part of plans to develop a propulsion system meeting aircraft manufacturers' future needs towards 2030.

Safran and its partners in the Clean Sky programme have received €65m in funding from the European Commission for this project, over a period of eight years. 

The Open Rotor — a highly refined version of the Unducted Fan or propfan concept that emerged in the 1980s — features two counter-rotating, unshrouded fans, allowing it to reduce fuel consumption and CO₂ emissions by 30% compared with current CFM56 engines.

Launched in 2008 and led by Safran, the demonstration programme has already reached several major milestones, including wind-tunnel tests at French aerospace research agency ONERA, leading to the assembly of a demonstrator in 2015, and the start of ground tests on the open-air test rig in Istres in May 2017.

Safran is exploring other propulsion solutions as well, in particular the UHBR (Ultra High Bypass Ratio), a shrouded turbofan engine with a very high bypass ratio, which would reduce fuel consumption by 5-10%. The company sees the UHBR as a credible solution for aircraft-makers towards 2025, because it could be easily integrated on current aircraft. Safran is also studying distributed, electric and hybrid propulsion systems.

At the Istres site, Safran now has a new test stand covering some 80,000m² (864,000ft²), the only one of its kind in Europe. It will be used to test the new-generation LEAP turbofan and future upgrades, the Open Rotor and UHBR technology demonstrators, and engines with complex architectures and/or of large size.