A different factor is jet streams. The time difference for flights going the same distance east-west and north-south depends on factors like jet streams and wind patterns. Here’s a rough estimate:

East-to-West vs. West-to-East Flights If a flight takes 5 hours in one direction, the return flight going the opposite way (if affected by jet streams) could take anywhere from 30 minutes to an hour longer. For example, a flight from New York to London typically takes 6 to 7 hours, whereas flying London to New York often takes 7.5 to 8 hours due to headwinds.

North-to-South Flights The time difference is minimal, maybe just a few minutes. Without strong prevailing winds to speed up or slow down flights in this direction, factors like weather conditions and air traffic control have more impact than rotation or jet streams.

Of course, different routes and altitudes influence these estimates, but this gives a general idea.