Heathrow is planning to build a third runway, north-west of the existing two. If built, it would introduce regular air traffic over parts of London and the South East that are not currently affected by aircraft noise. This project maps the noise impact of all of Heathrow’s runways, including the proposed expansion.

While the third runway remains at the planning stage, its likely location and operating patterns are now well established. Decades of design work, consultation, and technical studies have produced a large body of public information. Much of this material exists only as dense, technical PDFs, making it difficult to understand what the expansion would mean on the ground.

This web platform translates that material into clear, spatial visualisations. It shows where aircraft would fly, how noise would spread, and which neighbourhoods would be affected—making the impact of the third runway easier to see, explore, and assess for people living in London and west of the airport.