Technical problems

It does not take much to disrupt the nation's air traffic: an FAA computer problem suffices.

The Federal Aviation Administration blamed a computer glitch early Thursday to explain how numerous flights were delayed, causing cancellations throughout the country.

A circuit board at a computer center in Salt Lake City failed about 5 a.m. That prevented air traffic control computers from communicating with each other. Flight plans, usually transferred automatically, had to be typed in.

Some of the worst problems were reported in Atlanta, Chicago, Washington, D.C., and the New York metro areas, among others. The four-hour snarl elicited a comment from Sen. Charles Schumer, D-N.Y., who said the country's aviation system is "in shambles."