AA 3972 then UA 4645 at O'Hare
Bloomington-Normal → Chicago → Fort Wayne
Timetable, Chicago time
15:45AA 3972 from Bloomington-Normal at the gate
11:25UA 4645 to Fort Wayne leaves the gate
19 h 40 apart on the timetable, overnight
UA 4645 leaves 19 h 40 after AA 3972 arrives on the timetable: more than half a day, so not a connection we count.