When planning a mission to another planet, or even the moon, a big challenge is testing the sensors and instruments that actually land the payloads on the planetary surface. In this video, Draper Laboratory demonstrates how their Guidance Embedded Navigator Integration Environment (GENIE) -- a guidance, navigation, and control system -- can control a Xombie suborbital rocket under realistic flight conditions. The tether is just for safety. From Draper Laboratory:
Aircraft available to test NASA instruments today are unable to fly at the desired trajectories for planetary landings, and computer simulations are used to generate that data. However, a GENIE controlled flight vehicle could mimic a spacecraft’s final approach to the Moon and Mars here on Earth. Emerging and advancing future space technologies will then have the opportunity to fly their payloads terrestrially to raise their overall Technology Readiness Level and show that they are ready for use in space.