AA 643 then AA 2682 at O'Hare
Los Angeles → Chicago → Boston
Timetable, Chicago time
18:00AA 643 from Los Angeles at the gate
19:59AA 2682 to Boston leaves the gate
1 h 59 apart on the timetable
The last days
AA 643 and AA 2682 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.