AA 9867 then AA 6486 at O'Hare
Marquette → Chicago → Detroit
Timetable, Chicago time
13:05AA 9867 from Marquette at the gate
13:34AA 6486 to Detroit leaves the gate
29 min apart on the timetable
The last days
AA 9867 and AA 6486 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.