ENOVAL focused on the development of new technologies for low-pressure components for medium-sized, large and very large turbofans incorporating geared turbofan technology. The research looked into higher overall pressure ratios of between 50:1 and 70:1, as well as higher bypass ratios of between 12:1 and 20:1 combined with increased overall pressure ratios of up to 70:1. Says Merkl: “The bypass ratio achieved in the ENOVAL programme is in the range of 14:1 to 16:1.” This results in improved propulsion efficiency, thus reducing fuel burn and pollutant emissions. “And, on top of that, this will bring the noise emitted by emerging engines down further, even below the noise level of the geared turbofan, which is already very quiet as it is now.” Just look at some figures: Noise can be cut by up to 1.3 dB and CO2 emission by up to five percent. For a typical medium-range aircraft, such as an Airbus A320, this would translate into savings of 1,200 tons of CO2 a year, the equivalent of the carbon dioxide emissions produced annually by electricity use in 325 average households.