LONDON (AP) Hundreds of flights were delayed or canceled at Britain's busiest airports Saturday after a technical glitch left the main air traffic control center unable to operate at full capacity.
National Air Traffic Services, which controls the crowded airspace over England, said it was having a problem switching between nighttime and busier daytime operations at its control center in Swanwick, southern England.
Spokeswoman Juliet Kennedy said the problem with an internal phone system was preventing staff opening new control positions to deal with busier daytime traffic, meaning the service was able to handle about 20 percent fewer flights than on a normal Saturday.
It estimated the problem would be fixed by about 6:30 p.m. (1830GMT, 1:30 p.m. EST)
Heathrow Airport Europe's busiest had delays of an hour or more on many departures, and canceled several dozen short-haul flights to destinations including; Milan, Istanbul and Nice, France.