Why use Averages? Why not base figures on the actual flying days?
A18. Since, in practice, flying does not take place on every day (and some stations have more flights than others), and in order to provide a standardised base for comparison across the whole scheme, we use a figure of 220, which is the number of flying days in a year, having deducted weekends and public holidays. The total numbers of aircraft movements are then averaged over the notional 220 flying days. Using this method results in higher noise levels being calculated than would occur if the average was based on the total number of days in the year. This approach increases the potential for a property to qualify for insulation under the scheme.
