In the world of aeronautics, the use of jet engines on passenger aircraft has been the norm since the de Haviland Comet made its first description in 1949. With higher power, the aircraft can fly faster to the destination and take off. higher to avoid turbulence in the air. This causes aircraft with turboprop engines to be used less and less.
At the Paris Air Show that took place today, CFM announced their Revolutionary Innovation for Sustainable Engines (RISE) engine has successfully undergone 100 tests and is now on track to be tested on the Airbus A380 aircraft by 2025.
RISE has a strange design because it is equipped with two pairs of propellers that rotate against each other like the Tupolev Tu-142 Bear aircraft engine. Through this open fan configuration, CFM says fuel consumption savings and CO2 reductions of up to 20% can be achieved.
The idea of using a jet engine with an exposed propeller is not a new idea. The General Electric GE36 UDF was tested in 1985 and the Safran Contra-Rotating-Open-Rotor (CROR) was tested in 2017. CFM is a joint venture company of GE and Safran so the previous knowledge was used to produce RISE.
The main issue with this type of engine is noise and safety issues if the fan is disconnected from the engine. According to CFM, in tests so far RISE operates more quietly than the LEAP engine currently used on the Boeing 737-MAX and Airbus A320 Neo. With industry players now trying to reduce fuel consumption and pollution, perhaps open fan engines like RISE will eventually be used on real aircraft and not just a test stage.