SpaceX "Grasshopper"

"On June 14, SpaceX's Grasshopper flew 325 m (1066 feet)--higher than Manhattan's Chrysler Building--before smoothly landing back on the pad. For the first time in this test, Grasshopper made use of its full navigation sensor suite with the F9-R closed loop control flight algorithms to accomplish a precision landing. Most rockets are equipped with sensors to determine position, but these sensors are generally not accurate enough to accomplish the type of precision landing necessary with Grasshopper."
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