AA 3977 then AA 3261 at O'Hare
Detroit → Chicago → Houston
Timetable, Chicago time
14:05AA 3977 from Detroit at the gate
17:10AA 3261 to Houston leaves the gate
3 h 05 apart on the timetable
The last days
AA 3977 and AA 3261 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.