Falcon 9 booster controlled-descent and landing tests
The Falcon 9 first-stage landing tests were a series of controlled-descent flight tests conducted by SpaceX between 2013 and 2016. The program's objective was to reliably execute controlled re-entry, descent and landing (EDL) of the Falcon 9 first stage into Earth's atmosphere after the stage completes the boost phase of an orbital spaceflight. The first tests aimed to touch down vertically in the ocean at zero velocity. Later tests attempted to land the rocket precisely on an autonomous spaceport drone ship (a barge commissioned by SpaceX to provide a stable landing surface at sea) or on terra firma on a concrete pad at Cape Canaveral.
The first test occurred in September 2013 on the sixth flight of a Falcon 9 and maiden launch of the v1.1 rocket version. From 2013 to 2016, sixteen test flights were conducted, six of which achieved a soft landing and recovery of the booster:
Since the January 2017 return to flight, SpaceX has stopped referring to landing attempts as "experimental", indicating that they have become a routine procedure (see Iridium-1 and CRS-10 press kits of 2017, compared with CRS-9 and JCSAT-16 of 2016). As of 30 March 2017[update] three landings have been performed (100% success) and one mission was launched in expendable configuration, not attempting to land.
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