AA 153 then UA 5548 at O'Hare
Charlotte → Chicago → Nashville
Timetable, Chicago time
11:42AA 153 from Charlotte at the gate
15:49UA 5548 to Nashville leaves the gate
4 h 07 apart on the timetable
The last days
AA 153 and UA 5548 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.