Flights were grounded for more than an hour in some of the nation's Western states because of a technical problem.
The AP reports:
"In addition, the Federal Aviation Administration said Wednesday its air traffic control facility had also temporarily stopped accepting additional flights into the airspace.
"The agency says some flights were diverted as it gradually restores the system.
"Officials at Burbank airport said some flights were again being allowed to take off."
According to the FAA's system map, Los Angeles, Las Vegas and Salt Lake City were most heavily affected, with average delays hitting 2 1/2 hours.
The Los Angeles Times reports that computer problems were to blame.