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Travel consultant estimates cost of closure at $26 million a day

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Airport handles around 1,300 flights a day

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Minister says government is looking at infrastructure lessons

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Airlines chief blasts Heathrow over contingency planning

By Joanna Plucinska, Tim Hepher and Muvija M

LONDON, March 21 (Reuters) - The closure of Britain's Heathrow is set to affect the global aviation system for days and cost tens of millions of dollars, experts say, raising questions over why better contingency planning was not in place at the world's fifth-largest airport.

Experts were in shock at the scale of disruption - the largest since the Icelandic ash cloud of 2010 - as they tried to estimate the cost and breadth of the repercussions caused by a fire at a nearby electrical substation that knocked out the airport's power supply and its back-up power.

"It is a clear planning failure by the airport," said Willie Walsh, head of global airlines body IATA, who, as former head of British Airways, has for years been a fierce critic of the crowded hub.

Heathrow is the busiest airport in Europe in terms of the number of seats or aircaft capacity flying in and out each day, according to data firm OAG. All of Friday's 1,332 scheduled flights were cancelled.

The blaze, which was reported just after 2300 GMT on Thursday, forced planes to divert to airports across Britain and Europe, with many long-haul flights simply returning back to their point of departure.

The shutdown comes less than a year after Heathrow told Britain's Civil Aviation Authority in a filing that it was "a leader in airfield resilience".

But several experts pointed to potential weakness in its back-up plans.

Travel consultant Paul Charles said Heathrow's closure could cost the aviation sector around 20 million pounds ($26 million) a day, with no guarantee the airport would reopen on Saturday.

"Heathrow is such a vital piece of the UK's infrastructure that it should have fail-safe systems," he added.

Tony Cox, an international risk management consultant, said: "I can't remember a piece of critical infrastructure being wholly shut down for at least a day because of a fire. I can't think of anything comparable."

The chaos also exposed the potential vulnerability of critical infrastructure at a time when security has risen to the top of the European agenda.

British police said counter-terrorism officers were investigating, but there was no initial indication of foul play in the substation blaze.

Energy Minister Ed Miliband said the fire had disabled back-up power and that engineers were working to deploy a third source.

Like most large airports, Heathrow has what's called an operational resilience plan, which sets out to identify risks that could upset operations. It was not immediately clear, however, whether back-up power had been singled out as a potential vulnerability.

In 2023, Heathrow completed a new energy strategy, pledging more renewable energy "whilst protecting the resilience of our energy network," according to its latest annual report.

Heathrow and the CAA did not immediately respond to requests for comments on contingency planning.

CLEARING THE BACKLOG

The closure is set to have days-long knock-on effects globally, leaving many passengers stranded as carriers reconfigure their networks to move planes and crews around.

British Airways has warned in the past that Heathrow is so overstretched that recovering from disruption can cause even more chaos, as planes and staff must be properly repositioned even as the facility runs at full capacity.

"There will be impact running on several days, because once aircraft are grounded somewhere away from an operation, they are stuck there with the crews operating the flights," said aviation consultant and network planning expert John Strickland.

Britain's airspace is among the busiest in Europe, and technical outages have raised concern in the past.

An outage of Britain's air traffic control system NATS in 2023 cost over 100 million pounds, according to the CAA.

Tim Green, head of department for electrical and electronic engineering at Imperial College, London, saw his UK-bound flight forced to turn back to North Carolina on Friday.

Speaking to Reuters, he described the complex arteries feeding into Heathrow, which consumed 271,080 MWh of grid electricity in 2023, according to its annual report.

"There's a lot going on at an airport," he said.

Heathrow must supply power to shops, restaurants, public spaces and emergency lighting, he said, while a separate category of electricity supply feeds safety systems like radars, navigation equipment and landing lights.

"Some of that will, of course, be backed up by emergency generators. But I think the airport would rather shut down some of its operations than accept more aircraft when it's in a compromised state like that," Green said. ($1 = 0.7730 pounds) (Reporting by Joanna Plucinska, Sarah Young, Muvija M and Andrew MacAskill in London, Dan Catchpole in Seattle, Tim Hepher in Paris; Editing by Alison Williams, Matt Scuffham and Joe Bavier)