Why are today’s flights numbers shown as flights per day but future flights shown as flights per hour?

Today’s flights are shown as a daily average; given the spread of flight paths seen today a daily average is more appropriate than an hourly figure as hourly figures would, for many places, be illogical figures such as 0.25 aircraft per hour.

Furthrmore, picking a colour coding scale that is meaning across the wide area covered by this proposal also means that it has not been practical to provide distinction in the concentration of todays flights above 35 per day – therefore the red colour coding indicates areas where there are 35 per day and up – including the final approach where all flights line up to land on the runway and so the red color coding can represent 300+ flights a day.  This does not detract from the consultation the key statistics of future flights (discussed below) present the higher figure.

The proposed changes would concentrate traffic onto fewer flight paths.  This means that most areas under today’s spread of flight paths would see a drop off in the number of overflights; however areas directly beneath the new routes would see a marked increase in flights.  We want stakeholders to provide feedback to help us determine which areas get fewer and which areas get more flights in the future.

We have therefore highlighted the maximum number of flights they may see in the future assuming traffic is concentrated on individual routes and not spread out as seen today across much of the consultation area (with the exception of final approach and initial departure); we show this as hourly figures because this  enables us to make distinction  between day, night and busiest hour traffic flows – we could not provide this detail with a flights per day unit.

Posted in: g) Analysis and Data