AA 3664 then AA 2911 at O'Hare
Buffalo → Chicago → Las Vegas
Timetable, Chicago time
12:29AA 3664 from Buffalo at the gate
17:20AA 2911 to Las Vegas leaves the gate
4 h 51 apart on the timetable
The last days
AA 3664 and AA 2911 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.