Sorry, let me tighten up what I said. When I said "air can be perfectly still" I didn't mean to imply no downward force was generated. That was obvious to me so

Sorry, let me tighten up what I said. When I said "air can be perfectly still" I didn't mean to imply no downward force was generated. That was obvious to me so I didn't add that bit. What I mean is that the air that a wing traverses through doesn't have to be moving already, aka wind or air current. The power of the engine pushes the wing through the medium, and the action of this of courses causes downward air movement and thus elevates the wing.