AA 9909 then UA 5210 at O'Hare
South Bend → Chicago → Detroit
Timetable, Chicago time
09:30AA 9909 from South Bend at the gate
13:00UA 5210 to Detroit leaves the gate
3 h 30 apart on the timetable
The last days
AA 9909 and UA 5210 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.