Hundreds of flights have been delayed or canceled at Britain's busiest airports because of a technical problem at a main air traffic control center.
National Air Traffic Service, which controls the crowded airspace over Britain, said Saturday it is having problems switching between nighttime and busier daytime operations at its control center in Swanwick, southern Britain.
Heathrow Airport and London's Stansted airport had departure delays from 30 minutes to two hours. Spillover delays were reported across Britain and at Dublin airport in Ireland.
The Association of British Travel Agents said the problem is unlikely to be fixed before 1400 UTC and residual delays and cancellations are expected to last throughout the day in Britain and Europe.