UA 5559 then AA 6238 at DFW
Chicago O'Hare → Dallas-Fort Worth → Amarillo
Timetable, Dallas-Fort Worth time
16:29UA 5559 from Chicago O'Hare at the gate
08:25AA 6238 to Amarillo leaves the gate
15 h 56 apart on the timetable, overnight
AA 6238 leaves 15 h 56 after UA 5559 arrives on the timetable: more than half a day, so not a connection we count.