AA 873 then ET 3511 at O'Hare
Atlanta → Chicago → Muscat
Timetable, Chicago time
12:29AA 873 from Atlanta at the gate
09:05ET 3511 to Muscat leaves the gate
20 h 36 apart on the timetable, overnight
ET 3511 leaves 20 h 36 after AA 873 arrives on the timetable: more than half a day, so not a connection we count.