Assessment of the Noise Immission along Approach and Departure Flightpaths for Different SFB880 Vehicle Concepts

Kurzfassung

The number of flight movements is further increasing in the future and some major airports are already at their capacity limit. Therefore, it becomes beneficial for short range aircraft to operate on regional airports as well. Short range aircraft with conventional high-lift systems, however, are not able to safely operate on the comparatively short runways of regional airports. Instead, new aircraft concepts are required that are equipped with an active high-lift system. Such an active high-lift system offers high lift coefficients and thus the ability for short take-off and landing. In order to ensure a sustainable growth in aviation, such new aircraft concepts also have to offer reduced fuel consumption and low noise on the ground. The Coordinated Research Center (SFB) 880 focuses on such an active high-lift system. This active high-lift system is comprised of a flexible leading edge device, referred to as Droop nose, and an internally blown flap at the trailing edge, referred to as Coanda flap. Within the SFB880, the active high-lift system is applied to several aircraft concepts. These aircraft concepts are equipped with different propulsion systems, that is, turbofan engines of different bypass ratio or a turbine-driven propeller engine. In this study, the noise prediction methodology for the noise assessment within the SFB880 is summarized and applied to the aircraft concepts. The assessment includes the noise at the three noise certification points as well as along a line of observers. The study also includes a preliminary uncertainty assessment in order to evaluate the reliability of the predicted noise on the ground. The results show that the SFB vehicles can provide significant noise reduction compared to a reference aircraft with a conventional high-lift system and turbofan engine. Most noise reduction can be achieved with the aircraft that is equipped with the ultra-high bypass ratio turbofan engine.