Heathrow runway lights: What happened and what are the consequences? Everything you need to know

A problem with the lighting system for the airport’s two runways was identified in the early hours of Wednesday morning

Flights at Heathrow Airport are slowly getting back to normal after problems with the runway lights.

Thousands of passengers booked to travel to, from and through Europe’s busiest airport have experienced delays and disruption. What happened, and what are the consequences?

What was the problem?

The lights on the runways of Europe’s busiest airport failed in the middle of the night. Because of the normal curfew, no flights were due in or out at the time. Early on Wednesday morning, Heathrow Airport issued a statement saying: “Our engineering teams are investigating a technical issue with the lighting system for the airport’s runways.

“We have activated our contingency plans and both runways are currently open and operational.”

So it was fixed – why the delays?

While a solution was devised, many long-haul flights departing for Heathrow from airports around the world were held on the ground.

Some heavy delays have built up, with knock-on impacts on later departures from the airport. British Airways has delays of two hours or more on arrivals from Atlanta, Baltimore, Boston, Chennai, Cairo, Hyderabad, Los Angeles, Montreal, San Diego, San Jose, Seoul and Toronto, as well as three New York JFK flights.

Because of the problems with arriving flights, many long-haul departures are delayed because aircraft are out of position.

British Airways says it is planning to run all its services, but it is forecasting delays of an hour or more on flights later today to Abu Dhabi, Bahrain, Baltimore, Bangalore, Chicago, Las Vegas, Miami, Mexico City, Moscow, New York, Riyadh and San Francisco.

The worst delay is this evening’s service to Bangkok, which is over three hours late.

What about the other airlines?

A Virgin Atlantic flight to San Francisco is running an hour late, and Air Malta has a three-hour delay on its service to the island. But BA operates more than half the flights to and from Heathrow, so it is always worst affected. In addition, it is more affected by any disruption at the airport, because Heathrow is its main base.

Could it happen again – and at a more inconvenient time?

Heathrow Airport hopes not. A spokesperson said: “Investigations continue to find the root cause of this issue and we apologise for any impact that this may have had on passengers.”

Are passengers entitled to compensation?

No, this counts as “extraordinary circumstances,” so no cash payout is due under the European air passengers’ rights rules. Furthermore because no long-haul flight is delayed by four hours, there is no automatic entitlement to a meal or refreshments.

But if the delay has a knock-on effect – for example a flight to New York with an onward link on the same ticket to somewhere else in North America – then the airline may need to provide accommodation before the next available flight.