section_path: Future expansion and plans/Runway and terminal expansion
section_name: Runway and terminal expansion
paragraph_text: Runway and terminal expansion
  
  There is a long history of expansion proposals for Heathrow since it was first designated as a civil airport. Following the cancellation of the Maplin project in 1974, a fourth terminal was proposed but expansion beyond this was ruled out. However, the Airports Inquiries of 1981–83 and the 1985 Airports Policy White Paper considered further expansion and, following a four-year-long public inquiry in 1995–99, Terminal 5 was approved. In 2003, after many studies and consultations, the Future of Air Transport White Paper was published which proposed a third runway at Heathrow, as well as a second runway at Stansted Airport. In January 2009, the Transport Secretary at the time, Geoff Hoon announced that the British government supported the expansion of Heathrow by building a third 2,200-metre (7,200 ft) runway and a sixth terminal building. This decision followed the 2003 white paper on the future of air transport in the UK, and a public consultation in November 2007. This was a controversial decision which met with widespread opposition because of the expected greenhouse gas emissions, impact on local communities, as well as noise and air pollution concerns.
  
  Before the 2010 general election, the Conservative and Liberal Democrat parties announced that they would prevent the construction of any third runway or further material expansion of the airport's operating capacity. The Mayor of London, then Boris Johnson, took the position that London needs more airport capacity, favouring the construction of an entirely new airport in the Thames Estuary rather than expanding Heathrow. After the Conservative-Liberal Democrat coalition took power, it was announced that the third runway expansion was cancelled. Two years later, leading Conservatives were reported to have changed their minds on the subject.
  
  Another proposal for expanding Heathrow's capacity was the Heathrow Hub, which aims to extend both runways to a total length of about 7,000 metres and divide them into four so that they each provide two, full-length runways, allowing simultaneous take-offs and landings while decreasing noise levels.
  
  In July 2013, the airport submitted three new proposals for expansion to the Airports Commission, which was established to review airport capacity in the southeast of England. The Airports Commission was chaired by Sir Howard Davies. He, at the time of his appointment, was in the employ of GIC Private Limited (formerly known as Government Investment Corporation of Singapore) and a member of its International Advisory Board. GIC Private Limited was then (2012), as it remains today, one of Heathrow's principal owners. Sir Howard Davies resigned from these positions upon confirmation of his appointment to lead the Airports Commission, although it has been observed that he failed to identify these interests when invited to complete the Airports Commission's register of interests. Each of the three proposals that were to be considered by Sir Howard Davies's commission involved the construction of a third runway, either to the north, northwest or southwest of the airport.
  
  The commission released its interim report in December 2013, shortlisting three options: the north-west third runway option at Heathrow, extending an existing runway at Heathrow, and a second runway at Gatwick Airport. After this report was published, the government confirmed that no options had been ruled out for airport expansion in the South-east and that a new runway would not be built at Heathrow before 2015. The full report was published on 1 July 2015, and backed a third, north-west, runway at Heathrow. Reaction to the report was generally adverse, particularly from London Mayor Boris Johnson. One senior Conservative told Channel 4: "Howard Davies has dumped an utter steaming pile of poo on the Prime Minister's desk." On 25 October 2016, the government confirmed that Heathrow would be allowed to build a third runway; however, a final decision would not be taken until winter of 2017/18, after consultations and government votes. The earliest opening year would be 2025.
  
  On 5 June 2018, the UK Cabinet approved the third runway, with a full vote planned for Parliament. On 25 June 2018, the House of Commons voted, 415–119, in favour of the third runway. The bill received support from most MPs in the Conservative and Labour parties. A judicial review against the decision was launched by four London local authorities affected by the expansion—Wandsworth, Richmond, Hillingdon and Hammersmith and Fulham—in partnership with Greenpeace and London mayor Sadiq Khan. Khan previously stated he would take legal action if it were passed by Parliament.
  
  In February 2020, the Court of Appeal ruled that the plans for a third runway were illegal since they did not adequately take into account the government's commitments to the Paris climate agreement. However, this ruling was later overturned by the Supreme Court in December 2020. The plan stalled after a fall in passenger numbers during the COVID pandemic and concerns about investment costs, but came back into the spotlight after the Labour Party won the 2024 UK general election. The airport's CEO indicated in November 2024 that he would seek a "final" decision from the government by the end of 2025.