AA 1234 then UA 3302 at Charlotte
Pittsburgh → Charlotte → Louisville
Timetable, Charlotte time
07:34AA 1234 from Pittsburgh at the gate
13:37UA 3302 to Louisville leaves the gate
6 h 03 apart on the timetable
The last days
AA 1234 and UA 3302 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.