In a move hailed as historic, a city-suburban commission Friday overwhelmingly endorsed the biggest official change to O’Hare Airport’s night flight patterns in nearly 20 years.

The plan to rotate night runways every week should bring some periodic overnight relief to Chicago residents east of O’Hare, as well as Bensenville homeowners and others to O’Hare’s west.

Both areas have born the brunt of dramatic flight path changes that hit in October 2013 as part of an ongoing $8.7 billion O’Hare overhaul and an increasing reliance on east-west parallel runways.

Ever since, jet noise complaints have soared to record levels, catapulting past the 4 million mark last year alone. O’Hare jet noise even became an issue in the 2015 Chicago mayoral election.

The O’Hare Noise Compatibility Commission Friday voted 45 to 5 to begin a six-month test of the night runway rotation proposal. Experts touted the idea as unique in the nation.

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If approved by the Federal Aviation Administration, O’Hare could start weekly rotations of night runways, over 12-week stretches, as early as June. Reaction to the plan would be assessed before any longer-term one is implemented.

Under the proposal, calendars would be posted online outlining which one or two runways would be used each week over a 12-week period.

About 80 flights a night between the hours of roughly 10:30 p.m. and 5:30 a.m. would fall under the new schedule. That’s about three to five overnight flights an hour.

No one community would see noise two weeks in a row under the deal. Airstrips would alternate each week between east-west parallel runways and diagonal ones.

Commission Chair Arlene Juracek called the measure “historic” because it will mark the first official change to voluntary “Fly Quiet” rules governing O’Hare night flights since 1997.

The proposal offered both “predictability” and “balance,” Juracek said.

The change comes as more than 12,000 Chicago area residents complained specifically about O’Hare night jet noise in March alone.

Among the 45 communities and school districts approving the six-month test Friday were all six Chicago wards due for some relief under it – the 41st, 45th, 38th, 39th, 40th and 36th.

Voting no were five northwest suburbs impacted by the proposal’s increased use of a diagonal runway pointed toward them: Arlington Heights, Des Plaines, Hoffman Estates, Palatine and Rolling Meadows.

Des Plaines Ald. Malcolm Chester charged that the region’s northwest suburbs had suffered through jet noise for decades when O’Hare relied more heavily on diagonal runways.

“Finally, someone from the city is exposed to what we have been exposed to for 60 years,’’ Chester said. “Now that the city has an impact, they want a rotation to get it off the city.”

Another suburb affected by the same runway, Schaumburg, voted “yes.” But its representative, Karen Robles, said her vote was “predicated” on O’Hare following through with its plan to kill off the diagonal runway pointed Schaumburg’s way by 2019.

Chicago Aviation Commissioner Ginger Evans proposed the rotation plan under mounting pressure from the Fair Allocation in Runways citizen group and lawmakers to distribute air traffic more equitably.

FAIR’s continued support of the plan was contingent on the remaining diagonal runways staying open, its leaders said Friday. The plan’s heavy use of one diagonal due to be closed proves that diagonals are critical to O’Hare’s mix, said FAIR’s Dan Dwyer.

Another FAIR member, Don Walsh, warned that O’Hare’s rotational “Fly Quiet” plan should be mandatory. Otherwise, he said, pilots will request off-schedule longer runways or ones closer to the main terminal.

FAIR will be closely monitoring how often pilots seek to veer from the runway calendar during the six-month test, Walsh said.

“People can say, ‘This is the greatest thing since sliced bread’ but at the end of the day, pilots can say ‘I’m not gonna use it,'” Walsh said.

Doug Goldberg, a Chicago Aviation Department consultant, estimated three to six flights a night may need a longer runway than those scheduled.

However, he said, the city hopes to start a new “procedure,” already under discussion with airlines, in which it will ask pilots to notify O’Hare officials at least two hours in advance if they need a longer runway than planned that night, Goldberg said. Absent such a request, he said, off-scheduled runways will be closed.

Off-schedule runway requests and online citizen reaction will be among the items the city will monitor closely during the six-month test, officials said.

Some suburban areas will see more overnight activity under the plan, and other areas, including Chicago, will see less, but in total nearly 68,000 residents should experience less night jet noise under the proposal, according to one analysis. That’s presumably because it would send fewer planes over denser areas like Chicago.