Angle of attack

One mistake when you look at birds is to think that they are like planes, limited by the size of their wingspan. The truth is the birds (Those masters in flying) can change their wingspan at a blink of an eye. This allows them to fly through holes, dive on their targets or engage in aerial combat.

This is a raptor looking at something.

Brahminy Kite 

Then the swop. 

Brahminy Kite