AA 9928 then UA 1839 at O'Hare
New York LaGuardia → Chicago → Des Moines
Timetable, Chicago time
06:45AA 9928 from New York LaGuardia at the gate
20:25UA 1839 to Des Moines leaves the gate
13 h 40 apart on the timetable
UA 1839 leaves 13 h 40 after AA 9928 arrives on the timetable: more than half a day, so not a connection we count.