Computer Glitch Leads to Havoc in the Skies
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LOS ANGELES – Failure to perform a routine maintenance check caused the shutdown of an air traffic communications system serving a large swath of the West, resulting in several close calls in the skies, the FAA and a union official said yesterday.
In at least five cases, aircraft in the sky passed dangerously close to each other Tuesday night after the shutdown knocked out radio contact between pilots and air traffic controllers, the union official said. Two flights “were almost near-midair collisions,” said Hamid Ghaffari, local president of the National Air Traffic Controllers Association.
The Federal Aviation Administration said it was looking into five instances in which planes apparently got too close to each other during the communications blackout. In a statement, the agency said radio contact failed but radar coverage remained fully operational and aircraft were safely handed off to other air traffic control facilities.
The center hit by the blackout controls airspace for a vast region that encompasses California, Arizona, Nevada, and parts of Utah. The shutdown caused a ripple effect throughout the country as planes bound for the Los Angeles region were held on the ground for about three hours.
“A required 30-day maintenance check on the primary radio and voice communications system was not performed,” the agency said. “This system turns off if this check is not performed.”
It said a backup system also failed because it “was not configured properly to ensure its availability in the event of the primary system’s failure.” The problems could have been avoided if strict FAA procedures had been followed, the agency said.
Three workers filed injury claims, saying they were traumatized by seeing flights veer toward one another on radar without being able to do anything, he said. Airport operations were back to normal yesterday following the radio failure at an FAA center at Palmdale, north of Los Angeles.
During the outage, air traffic controllers could monitor planes on radar but were unable to communicate with them. Pilots had to switch to another radio frequency to communicate with other control centers that took over flights in the region.