The world
Kashmir at real scale, its airfields, the weather and time of day, and the map screen.
FlightOut has one map: the whole of Kashmir at real scale, about 800 by 690 km. It runs from the plains of the Punjab to the Karakoram and from Gilgit to Aksai Chin, with 25 real airfields. Everything on it is playable.

You choose the time of day and the weather for your offline flights. Online, the server chooses them for everyone.
Checked against FlightOut 0.5.1.