AA 1277 then ET 3511 at O'Hare
Denver → Chicago → Muscat
Timetable, Chicago time
18:19AA 1277 from Denver at the gate
09:05ET 3511 to Muscat leaves the gate
14 h 46 apart on the timetable, overnight
ET 3511 leaves 14 h 46 after AA 1277 arrives on the timetable: more than half a day, so not a connection we count.