John Strickland, an aviation consultant and former network planner at British Airways, said the airline appears to have made improvements in overall reliability, especially with respect to its fleet of A380 superjumbos, though challenges remain.
The next test for the airline will come next week amid a surge in transatlantic travel ahead of the Thanksgiving weekend.
A spokesman for Heathrow said that the airport’s systems were not affected and that after passenger safety, working to improve the resilience of flights is its number one priority.
In its email to staff, BA said that it became aware of a technical issue at 5:10pm and that all systems had been restored by 7:45pm.
Back-up networks were activated when the outage was detected and were able to calculate and distribute the required flight plans and load sheets.
Priority systems were back online within 61 minutes, while others, including the ba.com website, were up and running by 7.45pm.
The email said that while the incident was “very frustrating”, the speed at which BA was able to respond was testament to the impact of a £750m investment in IT as part of Mr Doyle’s £7bn transformation programme.
The email said: “What we saw last night was that our investment in our ability to recover our IT systems is making a difference. We’re steadily increasing resilience, and we’re recovering from these issues more quickly.
“We don’t seek to suggest this is ideal, far from it, but every time we experience these issues, our response gets better. We can assure you we’re looking closely at the cause of last night’s issue to understand how we can help prevent a future recurrence.”
BA said that had the event happened a couple of years ago it would have had a much greater impact and taken days to recover from. In the event, it ended the day with a 75pc on-time departure rate.
The company is part way through a move to migrate from its legacy data centres to the Cloud, a move it said should be completed in the first half of next year, further improving resilience.
BA flights were grounded for 36 hours in 2017, disrupting travel for 75,000 passengers, when a power surge damaged servers at its data centre.
An IT failure in May 2023 caused more than 200 flights to be grounded, affecting over 30,000 passengers across a bank holiday weekend, while the company was a victim of a global outage in July that led to thousands of cancellations across the industry.
The meltdown was triggered by a software update at cybersecurity firm CrowdStrike that affected Microsoft-operated systems at dozens of airlines and airports for 72 hours.
A BA spokesman said there have been no major IT issues for more than a year and that last Christmas passed without incident