Heathrow’s boss will be questioned by MPs on Wednesday about the airport’s closure for most of a day last month.
Chief executive Thomas Woldbye will give evidence to the Transport Select Committee as part of its investigation into the shutdown on March 21, which disrupted more than 270,000 air passenger journeys.
The west London airport was closed to all flights on that day until about 6pm, after a power outage caused by a fire at a nearby electricity substation which started late the previous night.
The committee will examine whether the situation could have been handled differently and what lessons can be learned.
Mr Woldbye will be asked why the airport was closed for so long, and why it appears to have a single point of failure.
He will be asked whether alternative power sources could have been used earlier, after National Grid said two other substations could have powered the airport.
He could also be asked about reports that he went back to bed after the power outage began.
The committee will also question whether this type of incident was deemed so unlikely to happen that investing in additional resilience was thought unnecessary.
National Grid will be represented at the session by Alice Delahunty, president of its UK electricity transmission operations.
Also giving evidence will be Eliane Algaard, operations director of Scottish and Southern Electricity Networks, the company responsible for restoring power after the fire, and Nigel Wicking of the Heathrow Airline Operators Committee, which represents airlines that use the airport.
In the immediate aftermath of the fire, the National Energy System Operator was ordered by Energy Secretary Ed Miliband to investigate what happened and provide its initial findings within six weeks.
An internal review of the airport’s crisis management plans and its response is being conducted by former transport secretary Ruth Kelly, who is an independent member of Heathrow’s board.
The Metropolitan Police said the cause of the fire at the substation in Hayes is not believed to be suspicious.
