UA 4669 then DL 1716 at O'Hare
Madison → Chicago → Detroit
Timetable, Chicago time
13:54UA 4669 from Madison at the gate
14:44DL 1716 to Detroit leaves the gate
50 min apart on the timetable
The last days
UA 4669 and DL 1716 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.