BR 642 then UA 3811 at O'Hare
Anchorage → Chicago → Seattle (SEA)
Timetable, Chicago time
11:55BR 642 from Anchorage at the gate
12:30UA 3811 to Seattle (SEA) leaves the gate
35 min apart on the timetable
The last days
BR 642 and UA 3811 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.