What's the plan for a third runway at Heathrow Airport?

The enlargement of Heathrow Airport is expected to beryllium welcomed by Chancellor Rachel Reeves connected Wednesday, aft years of heated debate.

The move, alongside confirmation of the enlargement of different London airports including Gatwick and Luton, is apt to beryllium met by fierce opposition.

Critics accidental expanding aerial question would marque it overmuch harder for the UK to conscionable its clime alteration commitments.

However, Chancellor Rachel Reeves has told the BBC: "Sustainable aviation and economical maturation spell manus successful hand."

Heathrow is already the UK's busiest airport, serving much than 80 cardinal travellers a twelvemonth with its 4 rider terminals and 2 runways.

A 3rd runway would mean demolishing hundreds of homes, diverting rivers, and rerouting the M25 motorway betwixt junctions 14 and 15 done a passageway nether the caller runway.

The fig of flights, presently capped astatine 480,000 a year, could spell up to 720,000 - oregon astir 2,000 a time connected average.

Heathrow told the BBC that it would yet beryllium capable to service up to 140 cardinal passengers a twelvemonth erstwhile the 3rd runway is successful operation.

The airport's owners, which see Saudi Arabia and Qatar's sovereign wealthiness funds and backstage equity steadfast Ardian, said the costs of enlargement would beryllium met by charging airlines for usage of the larger airport.

But aft years of wrangling implicit the archetypal plans, the archetypal outgo estimation of £14bn volition request to beryllium revised.

Even with authorities backing, the ceremonial readying process could instrumentality up to 2 years.

Any readying determination could past beryllium taxable to a judicial review, arsenic good arsenic needing to reply questions from opponents implicit biology concerns.

Local authorities and adjacent residents volition besides person questions.

After each that, operation is expected to instrumentality different six of 7 years.

A 3rd runway was archetypal projected by Gordon Brown's Labour authorities successful 2009 but was lone yet fixed the go-ahead by the Supreme Court successful 2020.

Several members of the existent authorities - including Prime Minister Sir Keir Starmer - voted against a Heathrow enlargement erstwhile successful opposition.

However, recently, there person been hints the Labour authorities would backmost a 3rd runway.

Starmer told the BBC that the authorities has clime commitments, "but maturation is truly important too."

Energy Secretary Ed Miliband said: "Any aviation enlargement volition lone beryllium capable to spell up if it is accordant with our c budgets".

However, London Mayor Sadiq Khan's bureau said helium has "a long-standing absorption to airdrome enlargement astir London" due to the fact that of the interaction connected aerial prime and noise.

Heathrow's boss, Thomas Woldbye, said successful December helium was waiting for a "clear steer" from the authorities earlier helium could instrumentality plans forward.

Some arguments for investing successful the UK's transport infrastructure see a boost successful growth, much jobs, and assistance for UK exports.

Other European cities boast hub airports with much runways, including Amsterdam which serves less passengers than Heathrow but has 5 runways. Paris Charles de Gaulle and Frankfurt person four.

Currently, implicit £200bn of British commercialized passes done Heathrow annually. Heathrow has not devised figures connected however overmuch commercialized is expected to summation aft a 3rd runway, which it volition bash erstwhile it arrives astatine readying stage.

The Airport Commission, an autarkic sheet that examines the request for further UK airdrome capacity, looked into the apt interaction of Heathrow enlargement and reported successful 2015 that determination would beryllium benefits to the tune of £61bn implicit 60 years.

It said that included reduced fares, less delays, greater resilience, and the instauration of up to 77,000 jobs.

Forging up with Heathrow enlargement would besides nonstop a wide connection to overseas investors that the authorities means what it says astir making maturation its priority.

However, immoderate critics, including deliberation vessel the New Economics Foundation say the interaction connected maturation is exaggerated, arguing much capableness successful the southbound of England mightiness simply displace enactment from different regions.

Aviation is 1 root of damaging emissions that tin lend to clime change, and the manufacture is nether unit to find ways to trim its impact.

Reeves pointed to advancement connected creating sustainable fuels, and electrical planes. A 3rd runway astatine Heathrow would besides mean "that alternatively of circling London, flights tin land" she added, meaning little substance is used.

But it is acold from clear that those technologies volition beryllium capable to marque up for the increasing request for aerial travel. Heathrow volition person to beryllium that its program meets the governments net-zero by 2050 targets successful immoderate readying application.

Last twelvemonth the government's autarkic advisor connected cutting emissions, the Climate Change Committee, warned that the UK should not spell up with airdrome enlargement without a model successful spot to negociate capableness crossed the country.

Friends of the Earth has described the program for a 3rd runway arsenic "hugely irresponsible".

Alethea Warrington, caput of aviation astatine clime foundation Possible, said: "This immense summation successful emissions won't assistance our economy, and would conscionable promote the tiny radical of predominant flyers who instrumentality astir of the flights."

Plans to grow London's different airports are already further on than Heathrow's and person successful the past been viewed arsenic an alternate to a 3rd Heathrow runway.

Work is acceptable to commencement this twelvemonth to grow capableness astatine Stansted's terminal.

The authorities is owed to marque a determination connected Gatwick airdrome by 27 February.

Gatwick wants to summation its capableness to 75 cardinal passengers per year, according to antecedently published plans. Pre-covid, its grounds was 47 million.

Meanwhile, a determination connected Luton airport's expansion, which includes plans for a caller terminal, is owed by 3 April.

In full these expansions could make capableness for much than 60 cardinal other passengers by the 2040s.