UA 2278 then AA 4527 at O'Hare
San Francisco → Chicago → Baltimore
Timetable, Chicago time
05:04UA 2278 from San Francisco at the gate
14:50AA 4527 to Baltimore leaves the gate
9 h 46 apart on the timetable
The last days
UA 2278 and AA 4527 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.