In Autumn 2016 the Government gave a ‘green light ‘ to a 3rd runway at Heathrow. That doesn’t mean to say it will be built. There will be a consultation on the proposals in 2017. Parliament will vote on the proposal at the end of 2017 or in early 2018.
Then Heathrow Airport must consult on detailed proposals for a third runway before they go before a planning inquiry. Heathrow does not expect to get final permission for a third runway until 2020 or 2021. It will not open before 2024 or 2025.
There is still a lot of opposition to a third runway. The proposal will face legal challenges in the courts. It will face a lot of opposition from local residents. And it will face serious direct action.