Noise Reducing Airflow Deflector for A320 Family
A320 Family aircraft may emit a tonal noise from the wing Fuel Over Pressure Protector (FOPP) cavities when making an approach to land. This has occasionally lead to complaints from residents under the approach path at distances of between 50 and 12 Km from the landing point.
Air Flow Deflectors fitted just forward of the FOPP relief holes will soon be available as standard fit on new deliveries and as a retrofit for in-service aircraft. These deflectors can reduce the subject tonal noise by up to 11 dBA, (depending to the approach trajectory), but it should be noted that they do not affect the aircraft’s ICAO noise level certification. The deflectors’ have negligible impact on aerodynamic efficiency and weight (147g per aircraft) which means that the aircraft’s performance is unaffected.
For retrofit, typically about 10 man-hours are required for installation while elapsed time is around 7 hours.