PSSSSSSST! It's called perspective.
Notice how the pilot has to look through the gun sight (where the AH views are centered)
It's not in the dead middle of the dash, and while you don't really get the impression, the frame appears to bend in (I assume anyway) because of the proximity of the pilot's face to the wind screen.
While AH is not capable of emulating a pilot focusing on various objects in his field of vision (zoom kinda works though)...it keeps everything within the set view in focus (and appears that the center of the screen is the main focal point, and the gun sight is the a good example)
Notice how the gun sight stays to true dimensions, but how the things surrounding it can be distorted...canopy frames, wings, dash, etc that increase the further away from the center of the screen and from the distance to the object (wings get very distorted in front left and right quarters)
It seems very relative to real life distortion of images outside of focus...the further away from what your focused on the more it seems to slant in. If ya don't believe it, try it...
I think thats what AH tries to emulate.
Oh well, makes sense now, prolly won't later.