Members of an O'Hare noise committee voted for a third overnight runway rotation Friday, but conflicts between suburbs over whose residents get a sound sleep could make final approval dicey.
The Chicago Department of Aviation began a second runway rotation test April 30 in an effort to evenly distribute the nighttime din from O'Hare International Airport jets around the city and suburbs.
The third trial adopted Friday by the O'Hare Noise Compatibility Commission's Fly Quiet Committee is a 12-week rotation that balances parallel and diagonal runways. It could start in mid-July when the second test wraps up.
It's the first time the rotation won't include a major northwest diagonal runway (15/33) expected to be retired in spring 2018. And the absence of that runway and the inclusion of other diagonal runways will create some unexpected noise for suburbs such as Des Plaines and Elmhurst that are pushing back.
Overuse of Runway 4-Left/22-Right in the rotation "will dramatically increase the number of flights at night," Des Plaines 6th Ward Alderman Malcolm Chester said.
The noise commission's full board votes on the plan June 2.
For towns including Bensenville and Wood Dale, the rotation offers relief about 50 percent of the time for neighborhoods hard hit by jets.
"This is a closer approach to balancing runway use," Bensenville Village Administrator Evan Summers said. "There is going to be a balance between parallel and diagonals. One of our overarching goals is to achieve predictability -- there's nothing more predictable than parallel, diagonal, parallel, diagonal."
The plan committee members adopted in a 8-1 vote splits rotation of parallel runways that affect towns west and east of O'Hare.
An alternate Chester supported would have used the parallel runways 66 percent of the time.
"We have people with planes a couple hundred feet over their head," he said. "It's not only the noise impact; people are complaining about soot all over their cars and houses."
Schaumburg Transportation Director Karen Robles supported the latest rotation concept, but she wasn't sure how the full noise commission vote will go.
"It's going to be interesting," Robles said. "I hope there's enough interest in the value of the real-life data ... that trying it for 12 weeks has merit."
Meanwhile Al Rapp, a Park Ridge resident and member of the Fair Allocation in Runways group, sought to continue use of Runway 15/33 and argued the vote won't allow people "to put their head on the pillow at night and get a good night's sleep."
The first rotation was tried out July through December of 2016.
Data from the three tests will be used to develop an interim overnight rotation that could go into place after 15/33 is decommissioned until a sixth parallel runway on the north airfield opens in fall 2020.