Heathrow Airport bosses had been warned of potential substation failures less than a week before a major power outage closed the airport for a day, a committee of MPs has heard.
The chief executive of Heathrow Airline Operators' Committee Nigel Wicking told MPs of the Transport Committee he raised issues about resilience on 15 March after cable and wiring took out lights on a runway.
Politics latest: 'Disastrous' not to shut Heathrow during outage, airport boss says
A fire at an electricity substation in west London meant the power supply was disrupted to Europe's largest airport for a day - causing travel chaos for nearly 300,000 passengers, the committee heard.
"I'd actually warned Heathrow of concerns that we had with regard to the substations and my concern was resilience", said Mr Wicking, the head of a body representing more than 90 airlines using Heathrow Airport.
"So the first occasion was to team Heathrow director on the 15th of the month of March. And then I also spoke to the chief operating officer and chief customer officer two days before regarding this concern.
"And it was following a number of, a couple of incidents of, unfortunately, theft, of wire and cable around some of the power supply that on one of those occasions, took out the lights on the runway for a period of time. That obviously made me concerned."
Mr Wicking also said he believed Heathrow's Terminal 5 could have been ready to receive repatriation flights by "late morning" on the day of the closure, and that "there was opportunity also to get flights out".
"It is the most expensive airport in the world with regard to passenger challenges. So from our perspective, that means we should actually have the best service. We should have the best infrastructure," he added.
Other problems
The biggest challenge was getting information, Mr Wicking said.
The desire for information on the outage and closure was so large that a Teams call on the day of the closure was "maxed out" with "a thousand participants", he added.
However, Heathrow chief executive Thomas Woldbye said keeping the airport open during last month's power outage would have been "disastrous".
There was a risk of having "literally tens of thousands of people stranded in the airport, where we have nowhere to put them", Mr Woldbye told MPs.
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