TP 4399 then UA 2091 at San Francisco
Boston → San Francisco → Chicago O'Hare
Timetable, San Francisco time
20:55TP 4399 from Boston at the gate
06:35UA 2091 to Chicago O'Hare leaves the gatealso AC 5366, NZ 9309
9 h 40 apart on the timetable, overnight
The last days
TP 4399 and UA 2091 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.