AA 4576 then UA 1848 at Atlanta
Washington National → Atlanta → San Francisco
Timetable, Atlanta time
13:03AA 4576 from Washington National at the gate
19:18UA 1848 to San Francisco leaves the gate
6 h 15 apart on the timetable
The last days
AA 4576 and UA 1848 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.