AA 6446 then AA 9921 at Phoenix
Boise → Phoenix → Chicago O'Hare
Timetable, Phoenix time
07:55AA 6446 from Boise at the gate
12:00AA 9921 to Chicago O'Hare leaves the gate
4 h 05 apart on the timetable
The last days
AA 6446 and AA 9921 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.