Attempts to tell Heathrow airport’s sleeping chief executive that the airport had been closed because of a power outage failed because his bedside phone was on silent, an inquiry has found.
Thomas Woldbye was in bed as senior Heathrow staff decided to suspend operations because of a fire at a nearby electrical substation.
No flights operated at the west London airport until about 6pm on March 21 because of the blaze which started late the previous night.
More than 270,000 air passenger journeys were disrupted by the incident.
Heathrow commissioned an inquiry into what happened, led by former transport secretary Ruth Kelly, who is an independent member of the airport’s board.
The Kelly Review found that Mr Woldbye “was not involved” in the decision taken by the airport’s chief operating officer Javier Echave at 1.15am on March 21 to suspend operations until 11.59pm.
Mr Woldbye’s mobile was “on his bedside table” but he was unaware of multiple attempts to alert him to the situation as the device was on silent mode, the Kelly Review said.
Alerts known as F24 alarms were sent to Mr Woldbye’s mobile at 12.21am and 1.52am to activate emergency procedures, and Mr Echave tried to call him several times.
The report stated: “Although his phone was on his bedside table, Mr Woldbye reported that it did not alert him to the F24 alarms or to Mr Echave’s other calls because the phone had gone into a silent mode, without him being aware it had done so and he was asleep at the time.”
It added: “Mr Woldbye first became aware of the incident at approximately 6.45am on March 21, and received a debrief from Mr Echave.”
Mr Woldbye expressed “his deep regret at not being contactable during the night of the incident”, the review said.
The review recommended that Heathrow considers having a “second means of contact” to notify key individuals about critical incidents.
It concluded that the decision to suspend operations after the power outage was “correctly made” as this was “essential to protect the safety and security of people, as well as the integrity of the airport and the UK border”.
The report stated that on March 21, Heathrow began accepting limited flight arrivals from 4pm and departures from 8pm, before fully reopening on March 22.



















The inquiry found there “may have been opportunities to open parts of the airport slightly sooner” on March 21 but this “likely would have been only by a maximum of a couple of hours or so”.
Ms Kelly said: “The evidence confirms that Heathrow made the right decisions in exceptionally difficult circumstances.
“Whilst the disruption was significant, alternative choices on the day would not have materially changed the outcome.
“The airport had contingency plans in place, and the report highlights that further planned investment in energy resilience will be key to reducing the impact of any similar events in the future.”
Mr Woldbye said: "Heathrow exists to serve our passengers and airlines, which made the decision to close the airport in March because of the North Hyde substation fire tough, but necessary.
“We hope that all our stakeholders understand this was done to protect the safety of passengers and colleagues.
“We’re truly sorry for the disrupted journeys, and we understand the impact this had on so many of our customers.”
A spokesperson for the Heathrow Reimagined campaign, whose supporters include British Airways’ owner International Airlines Group and Virgin Atlantic, said: “Lessons must be learnt from the closure of Heathrow during March’s power outage, but the internal Kelly Review allows Heathrow to set and judge by its own standards.
“It fails to properly tackle the poor contingency planning and years of inefficient spending that left Heathrow vulnerable.”
The National Energy System Operator (Neso), which is also investigating what happened, published an interim report earlier this month which stated the cause of the fire remains unknown.
It is expected to publish its full report by the end of June.