Aircraft airframe noise: Investigation of aircraft noise in steep approach
Last updated on April 5, 2022
Airframe noise has been found to be the dominant source of noise for an aircraft on approach to landing. Airframe noise is made up of the HLD noise and landing gear noise. In order to reduce noise on the ground steep approach landing procedures can be used. Figure 1 shows a typical steep approach trajectory. Steep approach utilises a steeper glide slope than the conventional -3 deg glide slope. As a result the aircraft flies at a higher altitudes over residential areas close to the airport. Increasing distance to the ground reduces the noise on the ground significantly according to the inverse square law. In order to meet the decent velocity requirement for landing, spoilers are used as air brakes to slow down the aircraft. The aim is to understand the underlying flow dynamics of noise generation on a HLD with deflected spoilers in steep approach landing configuration. Based on the results we aim to develop noise reduction techniques that can be applied to the HLD configuration to reduce the noise impact due to deflected spoilers. A high-order time accurate aeroacoustics code SotonCAA is being used to perform the simulations.
