AA 3380 then AS 583 at O'Hare
Cleveland → Chicago → Seattle (SEA)
Timetable, Chicago time
09:00AA 3380 from Cleveland at the gate
09:30AS 583 to Seattle (SEA) leaves the gate
30 min apart on the timetable
The last days
AA 3380 and AS 583 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.