AIRCRAFT NOISETHE AERONAUTIC ORCS

OUR TEAM

• DJ• Aidan• Nick• Saatvik• Ryan

• Jean-Lou• Tyler• Josh• Elliot

CAUSES OF AIRCRAFT NOISE

Aircraft noise is caused by a variety of factors, including the engine, the airframe, the flaps, and the landing gear. The engine noise is a major factor in the overall noise output of an airplane, but the other factors also contribute. Aircraft noise is a problem because it causes adverse health effects and disrupts sleep.

ENGINE NOISE

Engine noise is the primary source of noise pollution from aircraft. Engine noise is controlled by modifying engines with devices like hush kits and chevrons. Chevrons work by smoothing the mixing of hot air from the engine with cold air outside. This mixing contributes to noise levels. Hush kit also work to reduce engine noise and are mostly used on older or smaller aircraft.

Hush Kit and Chevrons

AIRFRAME

The airframe consists of the wings, flaps, slats, and landing gear. Although the jet engines are the primary source of noise, the airframe is also a significant contributor to the total noise signature. The wings generate noise as “unsteady” airflow passes over them. Flaps and slats are devices mounted on the wings of a plane and used to control the angle of the plane. They also generate noise as they redirect airflow.

NEW DESIGNS

Several new designs have been created to reduce aircraft noise, such as the SAX-40 and the QSST-X. The Silent Aircraft is a concept design that is estimated to reduce aircraft noise by 25 dBA. These designs work by reducing the weight of the aircraft and using a triangular shape to reduce noise. SAX-40

IMAGE CREDITS

• Slide 3: Image taken by team.

• Slide 5: "Hush kit" on a Sud Aviation Caravelle" by Mattias Björklund - Licensed under CC BY-SA 3.0 via Wikimedia Commons and "GEnx-1B on Air India B787 (2)" by Olivier Cleynen - Licensed under CC BY-SA 3.0 via Wikimedia Commons.

• Slide 6: "Wing with one spar" by Dtom - Public Domain via Wikimedia Commons.

• Slide 7: SAX-40 – Silent Aircraft Initiative – Fair use (education).

• Slide 8: Image taken by team.