(CNN) — After problems caused by a two-day British Airways strike, London Heathrow is set to be plunged into further chaos this week, with climate crisis protesters planning to disrupt Europe's busiest airport on Friday.
Activists from Heathrow Pause, an extension of the Extinction Rebellion movement that brought central London to a standstill earlier in 2019, plan to fly drones within Heathrow's five kilometer exclusion zone, starting at 3 a.m. -- three hours before scheduled flights begin.
They say they'll fly at "regular intervals throughout the day," in a bid to ensure that no aircraft will be able to take off or land all day. Activists will give an hour's warning before each flight, and no drone will encroach on flight paths.
On average, 1,200 flights pass through Heathrow every day. If the protest takes place, it's likely to cause major problems for an airport that will only just be recovering from the effects of the recent airline strike.
Potentially adding to the chaos, several airlines operating in and out of Heathrow have told CNN that the airport has yet to brief them on the situation, despite claims to the contrary.
For passengers, it could mean more misery -- and they're unlikely to be eligible for any compensation if their flights are delayed or canceled, according to UK consumer group Which?.
Heathrow has vowed to keep the airfield open, using drone detection and "dynamic risk assessment programs."
But UK law enacted in March 2019 states that any drone flying within five kilometers of an airport risks endangering aircraft.
The exclusion zone was increased from one kilometer by the UK's Civil Aviation Authority (CAA) after the Gatwick Airport sightings grounded 1,000 flights, affecting 140,000 people in December 2018.
"In order to ensure that our operation remains open and safe, we are working closely with a number of stakeholders including the police, NATS [air traffic control] and the CAA to ensure that the UK's hub airport does not close," said a spokesperson for Heathrow.
"We have in place dynamic risk assessment programs which are carried out by airfield and security experts and at no time will safety be compromised."
Heathrow's week from hell
Gatwick grounded flights for three days in December 2018 after drone sightings
BEN STANSALL/AFP/AFP/Getty Images
The Heathrow Pause action comes at the end of a difficult week for the airport, with up to 280,000 passengers already thought to have been affected by the British Airways strikes on Monday and Tuesday. Flight prices were driven up by up to 2,100% by the industrial action.
British Airways expects knock-on effects to continue tomorrow, but for the schedule to be functioning as normal by Friday.
What's more, although Heathrow says that it had last week "updated our airport community," with news of the potential disruption, one airline said that the first it had heard of the Heathrow Pause protest was when CNN contacted it Tuesday.
A spokesperson for SWISS, which has six daily flights to Heathrow from Zurich and five from Geneva, said that the only information from the airport about forthcoming incidents was about the next British Airways strike, planned for September 27.
Singapore Airlines also said it had received no official notice from Heathrow. The flag-carrier said it expected to operate as normal on Friday.
CNN contacted 25 leading airlines at Heathrow to ask when the airport had alerted them to the potential disruption, and whether they had informed any passengers who might be affected. The others declined to comment.
If flights are delayed or canceled, passengers are unlikely to receive compensation, said Which? Travel's acting editor Naomi Leach.
"If [Heathrow Pause] goes ahead, the airport will be forced to ground flights -- and passengers are unlikely to be eligible for compensation as it would be deemed a circumstance beyond the control of airlines.
"However, airlines would have a duty to provide care to passengers. This means they should be rerouted for free, even if this means using a different airline or airport, as well as getting reasonable expenses, including food, refreshments, and accommodation."
A spokesperson for Heathrow said: "We agree with the need to act on climate change but driving change requires constructive engagement and action. Committing criminal offenses and disrupting passenger journeys is counterproductive and irresponsible."
Operating a drone within the exclusion zone could result in a jail sentence of up to five years. Five drone "pilots," who have been publicly identified, say that at the end of each flight they will call police and wait to be arrested.
Facing prison time
The British Airways pilots strike has already affected up to 280,000 passengers this week
Dan Kitwood/Getty Images
Deputy Assistant Commissioner Laurence Taylor, of London's Metropolitan Police, said his force would do "everything in its power to prevent and stop any such criminal activity," and urged protestors to "think twice," reiterating the threat of imprisonment.
"As recent drone incidents at airports have shown, drone use in restricted airspace has the capability to cause great disruption to the public at the airport being targeted and connecting airports internationally, and the Met takes its role in preventing that from happening very seriously," he said.
"We will be deploying an effective policing plan around Heathrow to police and detect any illegal activity."
Travelers due to fly Friday should contact their airline and arrive at Heathrow in plenty of time, said Leach.
"It is probably also a good idea for travelers to make sure they are covered by travel insurance in case things do go wrong," she added.