How do birds fly in a seemingly straight line instead of up and down when they flap their wings?

Question

How do birds fly in a seemingly straight line instead of up and down when they flap their wings?

In: Other

Answer 1

First of all, birds are totally not real.

Anyway

If you watch a larger bird take off, you’ll see it move up and down a bit with each flap, until it gets up to flying speed. But once a bird is moving forward through the air at its normal flying speed, it flaps in order to keep moving forward. It actually changes the angle of its wings so that the flapping motion moves it forward instead of up/down. Its forward motion takes care of keeping it airborne, so it doesn’t have to push hard downwards with each flap (which is the motion that causes to up/down bobble you see when it takes off).