AC 888 then AA 9600 at Heathrow
Ottawa → London → Chicago
Timetable, London time
06:30AC 888 from Ottawa at the gate
13:00AA 9600 to Chicago leaves the gate
6 h 30 apart on the timetable
The last days
AC 888 and AA 9600 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.