AA 9780 then DL 1865 at O'Hare
London → Chicago → New York LaGuardia
Timetable, Chicago time
13:35AA 9780 from London at the gate
14:30DL 1865 to New York LaGuardia leaves the gate
55 min apart on the timetable
The last days
AA 9780 and DL 1865 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.