UA 2471 then AA 6487 at O'Hare
Kansas City → Chicago → St Louis
Timetable, Chicago time
11:33UA 2471 from Kansas City at the gate
15:18AA 6487 to St Louis leaves the gate
3 h 45 apart on the timetable
The last days
UA 2471 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.