The CFM RISE open fan programme has cleared a series of engineering milestones that bring ground testing within reach, CFM International executives confirmed at a press briefing in London on 18 July 2026, on the eve of Farnborough Airshow 2026.
Gaël Méheust, President and Chief Executive of CFM International, opened the event by saying the company was ‘preparing the future of aviation’ through its CFM International RISE (Revolutionary Innovation for Sustainable Engines) programme. RISE covers three technology streams: open fan, compact core and hybrid electric systems.
CFM RISE open fan clears design reviews
Pierre Cottenceau, CFM International Vice President of Engineering, Research and Technology, said that in the five years since RISE was launched, more than 500 test campaigns have been conducted and over 500 hours of wind tunnel testing completed. ‘This gives us the confidence that we can now go to the ground testing of the open fan [later this decade],’ he said.
Preliminary Design Reviews (PDRs) of the open fan and outlet guide vane (OGV) airfoils are now complete, meaning CFM can begin building hardware for the ground test demonstrator. OGVs are the second row of airfoils behind the fan that direct airflow, and CFM describes them as ‘key to how the Open Fan design can achieve the same speeds and altitudes as turbofan engines flying today’.
Arjan Hegeman, GE Aerospace Vice President of Future of Flight Engineering, said the programme is working with real, full-scale hardware. ‘We’re testing real, full-size Open Fan hardware, showing real progress and a renewed ambition from CFM to advance the RISE programme and deliver the vital technology step-changes for durability and efficiency to power the future of air travel,’ he said.
According to Aerospace America, CFM is targeting a bypass ratio of 60:1 for the RISE architecture, a figure that would substantially exceed current high-bypass turbofan designs and underpin the efficiency gains the programme is projecting. CFM’s own RISE programme pages indicate these technologies could be available by the second half of the 2030s, though no firm entry-into-service date has been set.
Durability and acoustics testing under way
Hegeman also outlined durability test results, stating that an open fan ingests more than 50% less dust than ducted architecture, and that lower temperatures combined with reduced dust ingestion delivers ‘significantly more time on wing’. CFM has completed the compact core PDR and run more than 2,000 cycles of dust ingestion tests to evaluate next-generation high-pressure turbine (HPT) airfoil technologies in an engine core. Hegeman added that supercomputers in Germany and the United States are being used to optimise designs for both acoustics and aerodynamics.
On hybrid electric systems, both RISE programme owners are conducting active ground testing. GE Aerospace completed two hybrid electric engine ground tests within the last year, demonstrating feasibility with and without energy storage. Safran launched PHILEAS, a full-scale engine demonstrator at its Istres site in France equipped with two electric machines, designed for the next generation of short- and medium-range aircraft engines.
LEAP-1B durability kit gains FAA and EASA certification
Alongside the RISE update, CFM announced that the LEAP-1B HPT durability kit has received certification from both the Federal Aviation Administration (FAA) and the European Union Aviation Safety Agency (EASA). CFM says the kit will double engine time on wing in hot and harsh environments, an area of growing concern for operators in severe climates. The update is expected to reach customers in early 2027.
CFM also secured engine-level certification for the LEAP-1B reverse bleed system (RBS), a cooling system designed to cut the frequency of on-wing fuel nozzle replacements. Méheust said the combined effect of both systems will ‘increase time between shop visits while also reducing maintenance burden, especially for customers in severe environments’, adding that customers will see longer time on wing on top of the efficiency and reliability the LEAP platform already offers.
