December 09, 2000

Chicago Sun-Times

Quieter O'Hare routes clear autopilot tests

December 9, 2000


An initiative to keep more O'Hare Airport flights away from residential areas overnight is a step closer to reality now that simulation tests have been completed in Denver, apparently without a hitch.

"We thought the simulations were very successful in proving that the implementation should proceed, and now it's up to FAA" to review the findings and give the go-ahead, Assistant Aviation Commissioner Chris Arman said Friday.

The Advanced Flight Track Procedures would use existing cockpit technology to help departures adhere more tightly to flight paths that are preferred late at night because they generally avoid homes and follow highways and forest preserves.

The voluntary flight paths, which are part of Chicago's "Fly Quiet" program and differ depending on the runway, are already in use but not to the extent desired by noise-weary west and northwest suburbs.

Air traffic controllers give pilots compass headings to follow those paths, but the aircraft often veer slightly and unintentionally because of winds.

The new initiative should stop that because the cockpit computers, which store the preferred paths, automatically compensate for wind and other conditions that push an aircraft off course, officials said.

"Basically, the onboard flight management system, a computer, will be able to interpret existing navigation signals from the ground and create an image which tells the pilot or autopilot the exact headings, and any variations, to fly in order to maintain the accurate departure track," Arman said.

Between mid-November and Thursday morning, there were more than 300 simulated flights at a United Airlines' facility in Denver.

"We were simulating the abilities of variant aircraft types to fly these departure tracks with accuracy, repeatedly and even under extreme conditions," Arman said.

United's Joe Hopkins said the airline's simulators were used to "perfect the techniques," which someday could be tapped by other airports.

FAA spokesman Tony Molinaro said his agency will determine whether "all the users in the O'Hare system" can use the initiative. "But it's really too early in the process to offer any constructive comments or feedback."