AA 3486 then ET 3511 at O'Hare
Jacksonville → Chicago → Muscat
Timetable, Chicago time
14:20AA 3486 from Jacksonville at the gate
09:05ET 3511 to Muscat leaves the gate
18 h 45 apart on the timetable, overnight
ET 3511 leaves 18 h 45 after AA 3486 arrives on the timetable: more than half a day, so not a connection we count.