I am in nature,and I am watching hawks motion. I knew it before and saw it live now,that when the hawk see the animal that wants to eat,close its feather to go faster. I made a thought,and I would like to tell me if it is correct or anything is missed. I think that closing its feather,make air pressure smaller because its area becomes smaller,so its power becomes bigger(F,power = P,pressure * A,area). Also because its power becomes bigger,its acceleration becomes bigger too(F = m*a). For that reason we have bigger speed. (a = du/dt) Is that right? Thanks in advance.