AA 1253 then UA 5567 at San Francisco
Chicago O'Hare → San Francisco → Seattle
Timetable, San Francisco time
09:40AA 1253 from Chicago O'Hare at the gatealso QF 4697
16:17UA 5567 to Seattle leaves the gate
6 h 37 apart on the timetable
The last days
AA 1253 and UA 5567 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.