By James Pilcher
The Cincinnati Enquirer

Residents in the north-south flight path of the Cincinnati/Northern Kentucky International Airport may notice more planes in the late night and early morning because of an operational test being conducted by the Federal Aviation Administration.

The test, which began Monday, allows air traffic controllers to use all three runways - including the two north-south strips - between 11 p.m. and 7 a.m. The priority will still be on planes landing from the east and departing to the west.

The test is allowable by federal regulations to help find more efficient and safer landing patterns. It is to last 60 days, although airport officials say they would not be surprised if there were more such tests in the future.

The previous restrictions had kept all planes on the east-west runway between 10 p.m. and 7 a.m., unless weather required the other two north-south runways be used.

But DHL Worldwide Express operates mainly at night, and both Delta Air Lines and Comair are changing their schedules to include more late-night flights.

Airport officials say the airport handles more than 200 flights after 10 p.m. So controllers wanted to see what options would work best to optimize efficiency, reduce delays and decrease potential conflicts in from using the easternmost north-south runway, a restriction that would keep all Delta and DHL planes from using that runway after hours.

The provision was included primarily because of a legal agreement with Delhi Township and the Sisters of Charity, who operate the College of Mount St. Joseph, that stipulates noise cannot exceed certain levels.

Those agreements were reached just before the newest runway opened in 1991, although the new restriction will not apply to regional jets flown by Comair.

Bergen said that the FAA will not be studying the impact on noise, but will be analyzing radar data to see if the test improved efficiency and safety.

If the FAA wanted to make the procedures permanent, the agency would have to conduct another environmental assessment.

Barb Schempf, noise abatement manager for the airport, said the airport is conducting its own noise study during the test and comparing it to normal levels.

She also said she would not be surprised if the FAA conducted more tests after this one to find the optimal solution. "When we go with just one runway, we're not getting all the planes we have in and out as safely and effectively as possible," Schempf said.

"But we'll be checking the noise ourselves, and if that becomes an issue, we'll certainly address it with the FAA."

E-mail jpilcher@enquirer.com