AA 2343 then UA 5191 at O'Hare
San Diego → Chicago → Lancaster
Timetable, Chicago time
16:30AA 2343 from San Diego at the gate
08:50UA 5191 to Lancaster leaves the gate
16 h 20 apart on the timetable, overnight
UA 5191 leaves 16 h 20 after AA 2343 arrives on the timetable: more than half a day, so not a connection we count.