AA 4121 then AA 1211 at O'Hare
Green Bay → Chicago → Seattle (SEA)
Timetable, Chicago time
07:27AA 4121 from Green Bay at the gate
17:25AA 1211 to Seattle (SEA) leaves the gate
9 h 58 apart on the timetable
The last days
AA 4121 and AA 1211 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.