An air-traffic control outage last week across parts of four Western states stemmed from a software glitch sparked by the flight of a single, high-altitude U-2 Pentagon reconnaissance plane in the region, according to two people familiar with the details.
Preliminary information indicates that the problem—affecting roughly 500 flights in and out of Los Angeles International Airport alone—resulted from the temporary shutdown of a key element of the Federal Aviation Administration's ongoing, $40 billion traffic-control modernization effort, these people said.
The chain of events started with a flight plan that resulted in an improper computer code for the U-2's flight, according to one person, apparently prompting malfunctions that overwhelmed the computer system.
The system ultimately went into overload and shut itself down as a precautionary measure. read more
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