 Grasshopper v1.0 made its eighth, and final, test flight on October 7, 2013, flying to an altitude of (0.46 miles) before making its eighth successful VTVL landing.The technology required to successfully achieve retropropulsive landings—the vertical landing or "VL" addition to the standard vertical takeoff (VT) technology of the early decades of human spaceflight—has several parts.First, thrust must be greater than weight, second the thrust is normally required to be vectored and requires some degree of throttling.