AA 215 then ET 3511 at O'Hare
Cancún → Chicago → Muscat
Timetable, Chicago time
17:40AA 215 from Cancún at the gate
09:05ET 3511 to Muscat leaves the gate
15 h 25 apart on the timetable, overnight
ET 3511 leaves 15 h 25 after AA 215 arrives on the timetable: more than half a day, so not a connection we count.