AA 1618 then UA 5191 at O'Hare
Dallas-Fort Worth → Chicago → Lancaster
Timetable, Chicago time
15:19AA 1618 from Dallas-Fort Worth at the gate
08:50UA 5191 to Lancaster leaves the gate
17 h 31 apart on the timetable, overnight
UA 5191 leaves 17 h 31 after AA 1618 arrives on the timetable: more than half a day, so not a connection we count.