What happened?
More than 1300 flights have been disrupted following a fire at a nearby electrical substation, which supplies Heathrow, causing a power outage.
Emergency services were first called to the scene at 23:23 GMT last night, with the fire not under control until 06:28, the London Fire Brigade said.
Heathrow said that the airport will be closed until midnight of the 21st March, but warned passengers to expect “significant disruption over the coming days,” and said that it does “not have clarity on when the power may be reliably restored.”
A Heathrow spokesperson told the BBC that the airport does have back-up power for its most important operating systems, but restarting the alternative power takes time.
Energy secretary Ed Miliband described the fire as “catastrophic” but noted that it is too early to determine a cause.
Not just Heathrow affected
Flightradar24 said that 120 affected flights were already in the air when the fire occurred and that 1351 flights to and from Heathrow will be affected today.
Travel journalist Simon Calder said: “Gatwick airport is struggling to cope with the influx of diverted flights following Heathrow’s closure. It’s putting enormous pressure on resources like baggage handlers and UK border staff.”
Along with passengers and airports over 16,000 homes are without power along with two nurseries and two schools in Hillingdon – the London borough Heathrow is located in.
The M4 is closed between junction three and four along with the Terminal Fur spur roads.
What happens moving forward?
The Metropolitan police are leading an investigation into the fire because of the “impact on critical national infrastructure.”
They are working closely on the London fire Brigade and are keeping an “open mind” despite no foul play having been indicated.
Several Qantas airliners have been diverted to Paris, and United Airlines have cancelled all of their flights to Heathrow, along with Cathay Pacific – Hong Kong’s main airline.
All of Virgin Atlantic and British Airways Heathrow departing flights have all been cancelled for the rest of today.
The airport has been reconnected to power on an interim basis.
