How the glitch works is you are flying with the jetpack on and then while flying open your inventory and put on blade runners. This will keep the jetpack affect going and will launch you straight up into the air. To stop the glitch you have to put your jetpack back on and hit spacebar and you will slowly start falling again. This glitch isn't very critical just wanted for it to be know so that it can be fixed.
-PS You will die if you go to high in the sky.