In the early 90s, UA used to fly a DC-10 ORD-MKE and back, about 80 miles each way.

It would come into ORD on a red-eye at 5am and not be needed back at a gate until 9:15am to start boarding for a 10am flight back to the West Coast. Since they didn't want it sitting around for four hours, they had it put it to use. But where?

The MKE flight was the only one where the plane could get out and back in time to a destination with a big enough runway to handle the DC-10. If the redeye was late getting in, they'd just cancel the MKE run or swap in a smaller plane.