British Airways plans to operate a "near-full schedule" on Sunday, advising passengers to proceed to the airport unless otherwise informed. On Saturday, about 90% of scheduled flights were conducted after operations resumed on Friday evening.
The disruption began when a fire disabled a substation in Hayes on Thursday evening, leading to flight halts until Friday evening. Temporary measures lifted restrictions on overnight flights during the closure.
Heathrow CEO Thomas Woldbye reported that a back-up transformer failed during the outage, necessitating system shutdowns for safety and power restructuring from two remaining substations.
Initially led by counter-terrorism officers from the Metropolitan Police, the investigation is now under London Fire Brigade's jurisdiction as there is no suspicion of foul play. The focus will be on electrical distribution equipment.
Miliband stated: "We are determined to properly understand what happened and what lessons need to be learned." He commissioned NESO to explore broader energy resilience issues for critical infrastructure.
NESO is expected to report initial findings within six weeks to both the Department for Energy Security and Net Zero and Ofgem. Akshay Kaul of Ofgem assured that action would be taken if any breaches were identified, emphasizing confidence in national infrastructure resilience.
Lord Deighton confirmed Heathrow's own review: "We are committed to finding any potential learnings from this unprecedented incident." Ruth Kelly will lead this review focusing on crisis management plans and operational recovery improvements.
Transport Secretary Heidi Alexander stressed learning from this failure to maintain strong national infrastructure. She acknowledged efforts by Heathrow, National Grid, and emergency services in restoring travel but warned of possible ongoing disruptions.
The fire led to power loss in thousands of homes and over 100 evacuations due to a transformer catching fire at the substation. Heathrow remains Europe's largest airport with over 83.9 million passengers in 2024 alone.