Chicago’s O’Hare International Airport far and away drew the most jet noise complaints — and complainants — among the nation’s busiest airports last year.

O’Hare, tops in the nation in total operations, flew off the charts with more than 268,000 jet noise complaints in 2014. The No. 2 airport, Hartsfield-Jackson Atlanta International, had 162.

The closest contender among the 10 busiest U.S. airports was No. 10, John F. Kennedy International, with 23,657 complaints — or 11-times fewer than O’Hare, an investigation by the Chicago Sun-Times and the Better Government Association found.

The story was similar for the number of households that sent in those complaints, producing yet another superlative about Chicago following a dramatic shift in O’Hare flight paths in October 2013.

O’Hare averaged 2,483 complainants a month last year. Next closest: New York City’s JFK with 171. That’s 14.5 times fewer than O’Hare, a Sun-Times/BGA survey of airports showed. Atlanta had seven a month.

The findings illustrate the national scope of the challenge facing Chicago Mayor Rahm Emanuel’s new aviation commissioner as she tries to find jet noise solutions with community groups. Getting the Federal Aviation Administration, which controls air traffic, and the airlines to buy into the solutions will also likely be needed.

Patti Clark, program chair of aviation maintenance at Embry-Riddle Aeronautical University’s Worldwide campuses, called O’Hare’s landslide margins “eye-opening.”

“There’s obviously an abnormality here and it needs to be addressed,’’ Clark said.

Spikes in jet noise complaints routinely follow flight path changes, but O’Hare complaints have climbed almost steadily to record levels since the airport’s switch to using mostly east-west parallel runways. Another east-west runway is due to open in October.

The number of average monthly O’Hare complainants tripled in the 12 months after the traffic shift compared to the year before it, data shows. It has climbed almost every month since.

“If it hasn’t fallen off, and now there’s another runway opening, I think there’s enough evidence of complaints and issues here that it warrants some investigation and partnership and development of ways to address the problem,’’ Clark said.

Aviation Commissioner Ginger Evans considers jet noise “a primary concern” and is “actively exploring” solutions, Chicago Aviation Department spokesman Owen Kilmer said.

Evans is in the midst of three meetings with a coalition of community groups concerned about airport noise — the Fair Allocation in Runways, or FAIR. The meetings were negotiated by state lawmakers before Evans took office June 1 but after Emanuel ignored more than a dozen FAIR requests for a jet-noise sit-down.

“All potential steps to address these issues are on the table,’’ Kilmer said. “We are going to continue to hear from community groups involved in this issue and weigh carefully any potential solutions brought to our attention.”

“A black hole”

The Sun-Times/BGA investigation also found that seven of the nation’s 10 busiest airports, including No. 2 Atlanta and No. 3 Dallas, allow complainants to request a response. O’Hare is not among them.

“I’ve never heard of anyone getting a response,’’ said Darrin Thomas, a FAIR member.

Instead, complaints fall into “a black hole,’’ said Thomas, who developed a website that allows complaints about multiple flights in one visit. Such counts were excluded from the Sun-Times/BGA analysis.

“The city does absolutely nothing with those complaints other than present them to the [O’Hare Noise Compatibility Commission] and move on,’’ Thomas said.

Los Angeles International Airport offers to investigate five complaints per person a month. Three Atlanta noise complainants said they personally talked to an airport staffer, and some also got information in the mail.

O’Hare, in contrast, uses 311-nonemergency operators or online forms to collect beefs.

Far from helpful, U.S. Rep. Mike Quigley (D-Chicago) said, are 311 operators who have told constituents “close your windows.”

“We need a uniform, institutionalized system of complaint data, with appropriate follow-ups, for all airports,” said Quigley, who is among three congressmen to urge the city to pay for a dedicated noise complaint line manned by knowledgeable personnel.

Denver’s jet noise strategy

Many Chicagoans and suburbanites contend their sleep has been constantly disrupted, and they fear their property values are tumbling since the shift in O’Hare flight paths.

The big switch has brought new waves of jets arriving from the east — over mostly the 41st, 45th, 39th and 40th wards in Chicago — while funneling takeoffs to the west, over such areas as Bensenville, Wood Dale and Itasca. Previously, suburbs north and south of O’Hare bore the brunt of traffic from mostly diagonal runways.

“Our noise complaints are off the charts for the impact on people’s lives,’’ said Jac Charlier, a leader of FAIR, which represents more than two dozen impacted communities.

City officials insist the dramatic changes were needed to increase capacity and reduce delays that were affecting the national air traffic system.

When Denver opened a new airport in 1995 some 18 miles from its downtown, noise complaints also started soaring — many from areas 20 to 40 miles away, officials there say.

“We thought buying 53 square miles of land would provide enough of a buffer from surrounding communities as compared to the previous Stapleton Airport,’’ said Mike McKee, the airport’s noise abatement manager. “We got far more complaints off the bat.’’

Denver International Airport’s 12-month peak after its opening was nearly 12,500 complaints a month; O’Hare’s was almost three times that after its overhaul, airport records show.

Within two months, Denver airport formed a task force to attack the problem that included representatives of surrounding counties, McKee said.

Officials discovered more departures were using some runways than the FAA had predicted and some departures were turning earlier than anticipated, McKee said.

By the second year of operation, after a battery of task-force initiatives, complainants dropped in half, Denver airport data shows.

“Apples and oranges”

Kilmer said comparing Chicago to Denver amounts to comparing “apples and oranges.”

“O’Hare is a unique airport in that it was built, and communities built up around it,’’ Kilmer said.

James Chmura, mayor of Norridge, which like Chicago, has been hard hit by arrivals, doesn’t buy it.

“People say, `You moved by the airport,’ ’’ Chmura said. “No we didn’t. The airport moved by us’’ by switching flight paths.

Arlene Juracek, chairwoman of the O’Hare Noise Compatibility Commission, which is briefed regularly on sound-insulation efforts and noise complaints, noted that O’Hare’s changes didn’t involve just one flight path. Its $8.7 billion overhaul thus far has added two east-west parallel runways, with a third to launch in October.

O’Hare’s inability to roll out the last three runway changes in tandem, as planned, prompted an environmental “re-evaluation” that will be outlined at four FAA public meetings in August.

Quigley and FAIR advocate keeping open two diagonal runways due for decommissioning, so flights can be spread out more evenly, as well as more vigorous “Fly Quiet” overnight procedures.

“Until we begin to solve these issues or begin a change in operations to alleviate the extraordinary burden that certain neighborhoods are getting, there should be no discussion of new runways,’’ Quigley said.

“Never going to end”

Experts point to the aviation adage “If you’ve seen one airport, you’ve seen one airport.” Some O’Hare characteristics explain why its traffic changes can have uniquely massive noise consequences.

For starters, O’Hare last year saw the most operations in the nation—nearly 882,000 flights. Amid that huge volume, the reconfiguration devised under former Mayor Richard M. Daley planned to send 70 percent of arrivals over dense northern portions of the nation’s third-largest city — areas not used to such traffic.

And unlike JFK or Los Angeles Airport in the nation’s first- and second-largest cities, land-locked O’Hare offers no adjacent over-the-water flight options to lessen the blow to citizens.

O’Hare’s configuration was modeled on land-locked Dallas/Fort Worth International, the nation’s third-largest airport, with 17,200 acres. O’Hare, with 7,259 aces, sits on less than half of that.

Some airports buy adjacent homes before construction. O’Hare did, too, but even so, one new O’Hare runway ends only 3,500 feet from some Bensenville homes, officials there note. Some residents in that area have shown up at noise commission meetings, demanding Chicago “relocate” them and put them out of their misery.

Throw into that mix some subtle nuances — Chicago’s humidity can make jet engines work harder and city concrete can reflect jet noise — and you have the recipe for an avalanche of noise complaints.

Plus, FAIR and others, like Norridge’s Chmura, encourage complaints, hoping they will prompt solutions

With another runway opening this fall, complaints are “never going to end,” Chmura said.

This story is part of an ongoing series by the Chicago Sun-Times and the Better Government Association. Rosalind Rossi is a Sun-Times staff reporter and a BGA contributor. She can be reached at rrossi@suntimes.com.