DL 8868 then UA 297 at O'Hare
Tampa → Chicago → Nashville
Timetable, Chicago time
14:54DL 8868 from Tampa at the gate
15:37UA 297 to Nashville leaves the gate
43 min apart on the timetable
The last days
DL 8868 and UA 297 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.