Military Jet, Commuter Plane Came Close

CHICAGO -- An error by air traffic controllers caused a military jet and a commuter plane to fly close to each other over northern Illinois, the Federal Aviation Administration said Monday, arguing that they were never in danger of colliding.

The incident occurred less than a week after Sen. Dick Durbin, D-IL, called for a federal investigation into the work conditions of Chicago-area air traffic controllers, including whether there are enough to ensure runway safety.

A United Express jet headed to Lexington, KY, from O'Hare International Airport and the C130 military jet got within 3.17 miles of each other Sunday morning, FAA spokeswoman Elizabeth Isham Cory says in an e-mail.

"There was never any danger of collision, but the event violated the FAA's separation standards, which requires a 'bubble' of space around each aircraft," Cory says. "The pilots could always see each other. The planes' collision avoidance system never alerted. This was not a near-miss."

Minimum spacing between planes is five miles horizontally or 1,000 feet vertically, Cory says.

An experienced controller was supervising a trainee when they both instructed the commuter plane to climb to 23,000 feet, rather than its requested final altitude of 21,000 feet, Cory says. The C130 was flying at 22,000 feet.

Authorities are investigating, Cory says. Both controllers have been taken off duty and sent for retraining.

Durbin's request came a week after the General Accountability Office released a study showing that O'Hare International Airport had the second-highest number of near-collisions on runways between 2001 and 2006.

Controllers in the Chicago region have said they are weary and more error-prone after having to work six-day weeks because of staffing levels. The FAA has said the levels are adequate, despite controllers' complaints. Staffing was adequate on Sunday morning, Cory says.