When radar screens suddenly went dark at Palmdale's regional air traffic center on Tuesday, controller Bruce Bates and his colleagues knew instinctively what to do: They grabbed their cellphones and started calling for help.
The simple solution to a high-tech problem played out as pilots flying at high altitudes over Southern California and much of Nevada and Arizona tried in vain to reach controllers in the Los Angeles Air Route Traffic Control Center, where even the radios were dead.
The trouble had begun an hour before, when a traffic accident downed power lines to the facility, triggering backup generators.
But those units were soon also knocked out, federal officials said Wednesday, by a system of surge protectors designed to avoid just such a crisis.
"The anxiety level definitely shot through the roof," Bates said, describing the scene. "We have seen glitches like a pop in the system, but the system keeps functioning. When it didn't come back on after about 10 to 15 seconds, all of us knew there was a major problem."
The phone calls for help went to controllers at other centers across the West, and they ultimately guided pilots to their destinations.
Federal officials said there were no close calls between aircraft as a result of the two-hour power outage at the Palmdale facility Tuesday evening. But controllers said it could take weeks to analyze radar data to ensure that safety wasn't compromised by planes flying too close to one another.
The center, which directs commercial jets flying at high altitudes, initially lost power after a truck hit a nearby utility pole around 4:19 p.m. Backup generators kicked on immediately. But about 75 minutes later, a system designed to protect sensitive equipment failed, causing radar to go dark.
The outage snarled air traffic across the country, causing hundreds of flights to be held on the ground in other cities while controllers in Oakland, Salt Lake City and Albuquerque diverted flights already in the air away from the Los Angeles Basin.
On Wednesday, local officials demanded to know why backup systems weren't more robust. An aide to Los Angeles County Supervisor Mike Antonovich, who represents Palmdale, said the supervisor asked Southern California Edison to provide a dedicated power line to the regional facility to prevent similar incidents.
"We want to ensure that a traffic accident in the Antelope Valley can't knock out air traffic control for the entire western United States," said Antonovich spokesman Tony Bell.
