A top official in the control tower at Minneapolis-St. Paul International Airport conceded Monday that the federal government should have revealed sooner that it was sending more flights over some neighborhoods.

"When we made that decision ... we didn't realize the impact, quite frankly," said Carl Rydeen, assistant air traffic manager.

"We didn't realize the number of flights that would happen."

Rydeen offered his assessment at a meeting of the Metropolitan Airports Commission, whose members stressed the need for better disclosure. The commission said it didn't learn of the change -- made after a near-crash about a year ago -- until last month.

"Should we have advised?" Rydeen asked. "We probably should have."

Commissioner Rick King told Rydeen it's important "when you do make a change, whether you perceive it to be significant or not, that we discuss it."

Flights over the Keewaydin and Ericsson neighborhoods on the city's south side increased by about 25 percent from January through August from 2010 to 2011. Air traffic from a runway closest to the neighborhoods jumped 33 percent.

Homeowners began noticing the extra noise in the spring but were puzzled by the cause. The Federal Aviation Administration, which runs the tower, was routing additional departures over the neighborhoods as a safety measure after a near-collision between a commercial jetliner and a cargo plane in September 2010. The routing, which already had been in effect for most flights, reduced the potential for planes to cross flight paths.

The FAA didn't tell the Airports Commission and a Minneapolis City Council member about the change until about two weeks ago.

While calling the lack of communication "an aberration," MAC Chairman Dan Boivin told Rydeen, "I understand that safety trumps anything. ... We just need you to let our communities know, sooner than later."

Rydeen explained that because the FAA had already been routing most northerly departures from a runway closest to the neighborhoods, the agency didn't think the additional takeoffs from it would make much difference.

"I noticed a substantial and significant difference," said Karl Starr, a homeowner in the area. "There are times now ... I can't have the windows open anymore. That is definitely new."

Alternatives to noise-proofing

The MAC's noise management says it doubts the increased flights over the two neighborhoods would raise noise levels sufficiently to qualify more homes for noise abatement programs.

"Is there anything that the FAA and the tower can do to still maybe decrease noise without putting flights in jeopardy?" asked Commissioner Paul Rehkamp.

Rydeen replied that the FAA was working on a new technology that could allow it to route planes more precisely -- over the Minnesota River, for example -- to avoid some residential areas. He said the technology could be ready in a little over a year.

But King said the additional precision could have a downside.

"It could be that somebody will get more noise than less noise when we implement that," he said.

MAC noise manager Chad Leqve agreed, adding, "I don't hold out a ton of hope in the south Minneapolis area."

Pat Doyle • 612-673-4504