QF 73 then UA 8177 at San Francisco
Sydney → San Francisco → San Diego
Timetable, San Francisco time
15:55QF 73 from Sydney at the gatealso AS 5001, AA 7397
19:25UA 8177 to San Diego leaves the gate
3 h 30 apart on the timetable
The last days
QF 73 and UA 8177 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.