DL 8858 then U2 8018 at Madrid
Atlanta → Madrid → London Gatwick
Timetable, Madrid time
07:35DL 8858 from Atlanta at the gate
13:40U2 8018 to London Gatwick leaves the gate
6 h 05 apart on the timetable
The last days
DL 8858 and U2 8018 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.