Data from travel intelligence firm Mabrian shows 108 flights were scheduled to depart the US to the UK yesterday, with 106 due to arrive. In addition, there were 47,920 domestic flights due to operate.

Heathrow schedules show only one US flight cancelled this morning and British Airways said: “We are not seeing any disruption to our services today.” Virgin Atlantic added: “We’re operating as normal now and saw minimal impact, just one delay yesterday.”

The all-clear was given at 14.30 yesterday after the source of the issue was found. The US Federal Aviation Administration said: “Our preliminary work has traced the outage to a damaged database file. At this time, there is no evidence of a cyber-attack.”

ABC News quoted a senior official saying an engineer had “replaced one file with another” without realising the mistake. The official added: “It was an honest mistake that cost the country millions.”

Mabrian estimates the most affected airport was Dallas/Fort Worth, American Airlines’ home hub, with 1,930 departures and arrivals timetabled. This was followed by Denver, Chicago and Charlotte.