Flight Istanbul Atatürk Airport departs from Istanbul Istanbul Atatürk Airport at 15:40 and arrives at Chicago O'Hare International Airport at 18:35.
The flighttime is about 10h 55m. The distance travelled ("as the bird flies"): 12978 Km. So the average speed is roughly 1189 Km.
There is an 8 hour time difference between Istanbul and Chicago
