DL 1622 then DL 5502 at Detroit
Chicago O'Hare → Detroit → Louisville
Timetable, Detroit time
10:52DL 1622 from Chicago O'Hare at the gate
12:59DL 5502 to Louisville leaves the gate
2 h 07 apart on the timetable
The last days
DL 1622 and DL 5502 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.