You must, however, remember not to jump when trying to catch air because you will jump away from the coping and into the half-pipe, thus giving your friends a good laugh. Just let the vert carry you up. If you're on a mini-ramp you do have to jump to get air. When you get your air, or when you think you can progress further, you have to do a 180 at some point so you can come down the ramp forwards again. This means you can pump a lot harder, and get more speed.
More speed means more air.
As you get higher and higher above the coping, your sense of fear will either disappear or will multiply to the stage where you become a nervous wreck at the bottom of the half-pipe. To avoid this from happening you need to get your 180 right so that you don't nail yourself. If you find you can't get any air, you're either not pumping enough, or you are letting up at the last minute, thus loosing all your speed. This is caused by fear. If you try and think about how good the air will look you won't be so afraid.