A fire at an electrical substation in West London caused a major power outage at the airport, prompting its closure
Emergency services were first called to Nestles Avenues in Hayes, West London at 23:23 GMT on Thursday 21 March. It involved a transformer containing 25,000 litres of cooling oil. London Fire Brigade had the fire under control by 06:28. The substation is about a mile and a half away from the airport. Videos shared on social media showed tall flames and plumes of smoke billowing from the substation overnight.
The cause as yet unknown, there was no indication of foul play as counter-terrorism police investigate. Having specific capabilities means they are used to conducting investigations quickly. They are also involved as the fire took place next to a critical piece of national infrastructure. The investigation will be focussed on the electrical distribution equipment and to find out why the substation’s back-up generator failed.
According to Flightradar 24, more than 1,300 flights were affected on Friday and passengers were told not to travel to the airport unless their airline advised them to.
National Grid announced that an interim solution had been found to restore power to customers including LHR. The network reconfigured.
LHR announced on Saturday morning it was open and fully operational; however flight disruptions are expected to last days. British Airways estimated 85% of its planned flights would run on Saturday, but with delays throughout. As of 07:00 GMT most departures had left as expected but 9 of the first 20 flights scheduled to land were cancelled.
So how could LHR be impacted so badly?
With it being such a busy airport for passenger journeys and global trade, questions have been raised over whether it has back-up systems in the event of power cuts. LHR does have back-up power for its key systems, but kickstarting these alternative power supplies for the whole airport takes time. There are multiple energy sources, with diesel generators and uninterruptable power supplies in place. In this instance, the back-up systems all operated as expected. However, they are not enough to run the whole airport, so the decision taken to close it down.
Once the power is back on, there are countless systems which need to be rebooted and checked to ensure they are working properly and it is unclear why LHR’s own back-up systems were not adequate to keep the airport running when one critical component of its energy supply was knocked out. It is also uncertain why the National Grid transmission network was not set up to supply sufficient electricity. All these questions would be investigated.
When the first flights took off on Friday evening, the priority was repatriation and relocation of aircraft. On Saturday morning, several flights cancelled and disruptions were expected to last days. The closure had knock-on effects at many other airports, as airlines cancelled and diverted flights. Several Qantas flights diverted to CDG.
Restrictions on overnight flights at LHR were temporarily lifted to ease congestion. Only 5,800 flights are allowed to take off or land at Heathrow between 23:30 and 06:00 each year, under government restrictions designed to limit how much noise the airport makes at night.
At least 1,351 flights to and from Heathrow were affected on Friday, with around 120 affected aircraft already in the air when the closure was announced.
British Airways cancelled all its short-haul flights to and from LHR on Friday. Some long-haul flights to CPT, JNB, SIN and GIG were later given clearance to depart from 1900 GMT. Cathay Pacific cancelled all its flights to LHR on Friday.
So, in a nutshell, that’s what happened
Obviously, investigations into the cause are ongoing. With the complexity of this incident, it could take some time before it is known and what will be done to prevent it happening again in the future. An independent energy consultant took to social media to comment on the event. She also asked why LHR did not have an independent power supply that was not reliant on outside sources. Another source called into question the lack of a resilience plan, taking the cynical view that as LHR is privately owned, it’s not considered important as no shareholder profit would be generated.
And finally….
Sky News – it didn’t take long before the first media howler appeared. At 0736 GMT on Friday morning, the flight cancellation situation was being reviewed. Questions started to be asked why the Special Air Service (SAS) logo was on the screen. A hapless journalist had confused a UK military unit with the Scandinavian airline SAS. It’s not known whether Sky News apologised for this oversight. DailyMailOnline also picked up on the error, this time it wasn’t them!
SAS – in a brilliant response to the above, the airline said –
“We get it, @SkyNews and The Guardian - same initials, both wear uniforms, operate internationally and move fast. But only one SAS was affected by the Heathrow power outage. Spoiler: it was the one with the free coffee onboard, not the one with parachutes.”
Delving deeper into the Twitter/X thread, SAS have made many friends with their witty response and actively engaging with everyone…
Information courtesy of BBC News, SAS (via Twitter/X)
Images courtesy of Deadline, FR24
©TPSC, LadyJet2 and photo/diagram suppliers