[Eli5] Why do planes need huge wings but space rockets don’t ?
In: Physics
Planes use wings to generate lift from forward flight; as the plane moves forwards through the air, some of the air is deflected downwards by the wing. Given the conservation of momentum, the force that the plane pushes down on the deflected air is equal and opposite to the amount of force that the air pushes back on the plane, thus if you deflect *enough* air such that the force is at least equal to the weight of the plane, the plane will remain in the air.
Rockets don’t care about lift, because there is no air in space, and because the part of the atmosphere that they do most of their flying in has very little air in it. This is deliberate because the same air that can be used to generate lift will also generate drag, and enough drag can actually seriously damage the rocket. Thus, a rocket will generally shoot straight up relatively slowly until it clears the thicker part of the atmosphere, and then tip over and throttle up to full power in order to get up to orbital velocity.
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