How we categorise aircraft noise
LCY operates an Aircraft Noise Categorisation Scheme (ANCS) based on a noise quota count (QC) system. Many UK airports run a similar system at night.
Each aircraft type is assigned a separate QC for arrivals and for departures, based on their certification noise levels and categorised into 1 dB (decibel) bands.
How widely do we measure aircraft noise?
The certification noise levels are measured at three points, known as approach, sideline and flyover. By allowing for arrival and flyover noise, the ANCS takes into account communities further to the east and west of the airport under the flight paths, as well as those closest to the airport.
The ANCS QC system has an annual limit, currently 22,000 per calendar year, with a maximum of 742.5 in any single week. We regularly review these limits – and our performance against them – with the London Borough of Newham.