Over the years, many Flight Simulator users have noticed that it isn't possible to fly over the north or south pole. Any attempt to do so results in the aircraft hitting an invisible "wall," where the program ceases to react in the manner the user is expecting. The plane will stand still or fly sideways, the ground textures will appear quite out of place, and in some earlyier versions of Flight Simulator, it was possible for a plane to get stuck and not be able to fly away from the poles if they got too close.

The reason for this is because the Flightsim world is not modelled in the exact shape that the real world has. The world real pilots are used to flying in looks someting like:

The Flight Simulator world is shaped something like:

The poles are compressed, making the shape of the world more like a squashed ball than a sphere. This makes it impossible for aircraft to travel beyond approximately 89.3^o north or south of the equator.

The reason this has been done is not completely clear, however it is reasonable to guess that mathmatics play a large part. It could be quite complicated to have the aircraft continue travelling consistently over the poles. It would be required that all elements of the location would have to be recalculated, longitude, latitude, heading and vector would all be affected, unlike crossing the International Date Line where only the longitude has to be recalculated, and it will always be the exact opposite to the position the aircraft was previously in.

The only element of the location that changes when crossing the date line is East or West, the same as when crossing the Prime Meridian. When crossing the Equator, only the North or South values change. But so many things have to be recalculated when crossing the poles, that it would be too easy for the plane to end up in the wrong place. An easy solution is to prevent this from happening in the first place.