DL 548 then DL 5638 at JFK
Phoenix → New York → Milwaukee
Timetable, New York time
06:07DL 548 from Phoenix at the gate
21:21DL 5638 to Milwaukee leaves the gate
15 h 14 apart on the timetable
DL 5638 leaves 15 h 14 after DL 548 arrives on the timetable: more than half a day, so not a connection we count.