‘The units will increase Heathrow’s noise monitoring capacity and expand its leading-edge noise abatement programme’, writes Aviation Media; for what it’s worth.
The big increase in noise monitoring stations are likely to provide a more accurate picture of noise around Heathrow. The airport will use this information in its efforts to reduce noise. It has introduced slightly steeper approach paths and is currently studying the impact that steeper departures may have. Aircraft will become a little quieter. Heathrow is also keen to give communities which currently experience all-day flying some respite from the noise by sharing it around more fairly.
Heathrow still bases its noise contours on average noise. Communities are pressing the airport to also use more meaningful metrics such as the ‘N’ metric – the number of planes which go overhead at given decibel levels. There are signs that Heathrow will move in this direction.
But, of course, it is the huge number of planes using Heathrow that remains the big problem. And this will increase by 700 a day if a third runway is built.