The first radio links with pilots were lost just as the pre-dawn crush of flights into Chicago began.
Air-traffic controllers in a nondescript Federal Aviation Administration building about 40 miles from the city switched to backup channels. Then those failed. They tried emergency connections, which also went dead.
Within minutes, radar feeds, flight plans and other data controllers rely on to direct more than 6,000 aircraft a day above five U.S. states had vanished as a fire was being set in a communications room one floor below. The attack was thorough and carried out by someone who knew the system intimately — down to removing steel sheathing on data cables to destroy them, according to three people with knowledge of the incident.
"I opened the door, walked in two or three steps," said Peter Hartman, a technician. "The smoke in there was just so thick you couldn't see your hand in front of your face."
The Sept. 26 outage, blamed on a suicidal communications technician, was the worst case of sabotage in the history of the nation's air-traffic control system. Thousands of flights were canceled across the country on the first day, a figure that fell to about 200 yesterday. The FAA said it may take until Oct. 13 to replace damaged equipment and fully recover.
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"It was fast," said Bryan Zilonis, a regional labor leader who used to work at the facility in suburban Aurora, Illinois, and was told what happened by his union members. As controllers started to clear out the airspace "the fire alarms went off and they realized something bigger was going on."
The attacker knew how to pull back the steel, protective cover so that it would be easier to destroy the wiring and fiber-optic cable, said the people familiar with the incident who asked not to be identified because the case is still under investigation.
The attacker also knew the system's multiple backups and was able to damage or destroy those key links in a short period of time, they said.
Brian Howard, 36, a telecommunications field technician for Harris Corp. (HRS), was charged Sept. 26 with setting the fire that day to the air navigation facility. His defense lawyer, Ronald Safer, said Sept. 30 that he and his client hadn't decided whether to contest the charge. Howard remains in custody and faces as many as 20 years in prison if convicted.
Hartman, a technician at the facility, known as the Chicago En Route Traffic Control Center, was testing an emergency diesel generator in the adjacent building when the fire alarm went off at about 5:40 a.m.
He called the operations center that monitors the technology systems and they told him the fire was in the basement room where Harris's communications network connects to the center's equipment.
Hartman rushed to the basement and called out through the smoke to see if anyone was inside. No one answered, so he retreated.
Howard was found there a short time later by paramedics who first spotted his feet under a table, according to an affidavit filed in court by an agent of the Federal Bureau of Investigation. He was shirtless, had cuts on his arms and was attempting to slit his throat, according to the document.
"The smoke was so thick and he could have been right next to me and I wouldn't have known it," said Hartman, who was treated for smoke inhalation at the scene.
Minutes before the attack, Howard posted a message on Facebook saying he was "about to take out ZAU and my life," using the FAA's three-letter call sign for the center, according to the FBI agent. The full Facebook post, obtained by Bloomberg, contained an anti-U.S. rant calling the government guilty of "immoral and unethical acts."
Howard worked for Melbourne, Florida-based Harris, which holds the FAA's main telecommunications contract. He had worked at the Chicago Center for eight years, according to an FBI affidavit. The company has fired him.
At about the same time Hartman was fleeing, controllers working in the dimly lit radar room on the center's main floor were instructing pilots to radio other air-traffic facilities and began to evacuate, said Zilonis, the regional vice president for the National Air Traffic Controllers Association.
The flat-screen panels that display aircraft radar tracks were useless, showing only where computers estimated the planes were headed, not their actual path, said Zilonis, whose union represents 15,000 controllers.
The damage below was so severe that the FAA has decided to rebuild the center's nerve system. Of 29 racks of computers driving the communications equipment, 20 were destroyed by fire and water damage, FAA Administrator Michael Huerta said Sept. 29.
After 2,000 cancellations of Chicago flights Sept. 26, disrupting travel across the country, that figure fell to less than 200 yesterday, according to FlightAware.com. Flight cancellations rose today to more than 700 as of noon local time as thunderstorms in the region complicated management of air traffic with the Chicago center still down.
Southwest Airlines Co. (LUV), which handles about 90 percent of the passengers at Chicago's Midway, has canceled the rest of its flights for the day, the Chicago Department of Aviation said in an e-mailed statement.
Last week's sabotage has spawned a massive response from controllers, technicians and FAA officials to keep the airways flowing. They have pulled 20-hour days installing new communications links and cobbled together a patchwork of flight routes allowing planes to reach airports including O'Hare International, which this year has taken over the title of busiest U.S. airport.
"It kind of burst our bubble at first," Gerald Waloszyk, an operations manager helping oversee repairs at the Chicago center, said in an interview. "But everybody has stepped up to the plate to get the system back on line."
Waloszyk, Like Hartman and other members of the Professional Aviation Safety Specialists, said they were speaking as members of their union, not on behalf of the FAA.
Even that first day the FAA and its employees were racing to resume service.
Long-range traffic plying the upper altitudes of the center's airspace, over five states surrounding Illinois, were redirected to other facilities.
Getting planes into and out of Chicago's airports was a trickier matter. Flights heading for Chicago would normally stay at altitudes above 30,000 feet (9,100 meters) until they reached about 100 miles from their destination. That was impossible with the center shut down.
Controllers and FAA managers devised a plan to bypass the center's airspace by descending planes far earlier and passing control to as many as 15 FAA radar facilities guiding planes around the region's major airports.
These facilities, known as Terminal Radar Approach Control or TRACONs, usually handle planes only as high as 11,000 feet (3,350 meters), Zilonis said. Controllers in normally quiet TRACONs in places like South Bend, Indiana; Peoria, Illinois; and Waterloo, Iowa, got a baptism by fire, he said.
"I'm very proud of them," he said. "There would have been just streams of jets coming through."
As the days have passed, the altitudes controlled by those TRACONs has been expanded to 17,000 feet to allow for more flights.
More than 100 of Chicago Center's almost 400 controllers have volunteered to temporarily transfer to these TRACONs and to four surrounding FAA centers so they can guide the traffic, Zilonis said.
An equal challenge has been replicating the nerve center of the region's air-traffic system. Phone connections between FAA facilities, radio systems and the flight plans that controllers use to identify aircraft were all knocked out.
Lee Leslie, a PASS member who works at the Chicago TRACON in Elgin, Illinois, knew there was "a big problem" as soon as he saw the TV news showing a fire in the center, he said in an interview. He had taken Sept. 26 off to prepare to take his 86-year-old father to a family reunion in Virginia the next day.
He canceled the trip and volunteered to work.
Over the next two days, he helped install dedicated phone connections known as "shout lines" between the TRACON and four other air-traffic centers. The same spirit has helped teams in Aurora working to patch the center, according to Waloszyk and the others working there.
In addition to cleaning and drying equipment after the fire, they've installed links allowing controllers in other facilities to use Chicago's radio frequencies.
"It is all hands," he said. "Everybody is pitching in."
To contact the reporter on this story: Alan Levin in Washington at [email protected]
To contact the editors responsible for this story: Jon Morgan at [email protected] Romaine Bostick, Steve Geimann