UA 503 then AA 4540 at O'Hare
Boston → Chicago → Houston
Timetable, Chicago time
12:29UA 503 from Boston at the gate
15:12AA 4540 to Houston leaves the gate
2 h 43 apart on the timetable
The last days
UA 503 and AA 4540 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.