U.S. prosecutors say a suburban Chicago contractor should serve 13 years in prison and pay $450 million for setting a fire at a radar facility and shutting down air traffic nationwide.

In a court filing Friday, prosecutors say Brian Howard was trying to "lash out" at his employer and government workers he thought were "lazy" when he set fire to a telecommunications room last year. The damage to the Aurora Federal Aviation Administration facility forced Chicago's O'Hare and Midway airports to close.

Howard pleaded guilty in May. Under the plea deal, he faces at least a decade in prison.

Defense attorney Ronald Safer says Howard is a good person who suffered from depression. He's seeking a sentence of 10 years plus a day.

Sentencing is scheduled for Sept. 11.