UA 6015 then AA 6487 at O'Hare
Milwaukee → Chicago → St Louis
Timetable, Chicago time
10:00UA 6015 from Milwaukee at the gate
15:18AA 6487 to St Louis leaves the gate
5 h 18 apart on the timetable
The last days
UA 6015 and AA 6487 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.