A maintenance technician stands accused of sabotaging the Aurora Control Center. As a consequence, planes destined to Chicago and a number of neighboring airports, including Milwaukee and Rockford, couldn't get in and therefore weren't able to get out. And cross-country planes had to divert to other routes, if paths were available. The center is so badly damaged that the Federal Aviation Administration warns travelers that full restoration of operations may not be finished until 13 October.
USA Today estimates that the air carriers will suffer losses reckoned in the tens of millions of dollars.
Put another way, your tax dollars contribute to the profitability of the air carriers. Keep that in mind the next time someone gripes about direct subsidies to Passenger Rail.