One of my favorites (despite day 1 emergency horse I had to use given altitude kicking my butt even after coming from Cusco)! (earthtrekkers.com)
Indeed, since pilots can not see other craft, and since controllers are not certain of the exact position of any given plane, aircraft are forced to make stepped landings: They descend to a given altitude, then level off, and then descend again. (discovermagazine.com)
This transition was characterized based on several criteria including an energy threshold and a given altitude beyond which the magnetic arcades that confine the rope become weaker. (sciencedaily.com)