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SpaceX's Autonomous Barge Lands Fourth Rocket

By MarEx 2016-08-15 21:29:56

There are many manufacturers and vessel operators interested in the concept of large autonomous ships, but there is only one firm that already has them in commercial service: the rocket company SpaceX, which operates the unusually-named barge conversions Of Course I Still Love You and Just Read the Instructions. The former deck barges have four azimuthing drives for stationkeeping and transiting, and SpaceX and NASA say that while the vessels do not travel far, they are equipped with an autonomous navigation system. They operate unmanned as landing platforms for used booster stages from SpaceX's Falcon 9 rockets; if recovered and reused, these boosters could shave tens of millions off the cost of each launch.

The landing-at-sea concept is necessary because some launches take the booster stage so far out over the Atlantic that it cannot make it back to land. It has not always worked in practice: on the first attempt, the rocket lost hydraulic fluid for maneuvering, hit hard and exploded on deck. In June, another rocket failed to touch down due to uneven thrust from one engine. 

However, none of the failures were attributed to the barge, and the firm appears to be closing in on a solution: on Sunday, it launched a comms satellite for Sky Perfect JSAT, and the booster stage successfully maneuvered down to the barge, some 370 miles from the liftoff point at Cape Canaveral. Sunday's recovery makes for four successful barge-top landings so far, in addition to two recoveries on land. The severe conditions of Sunday's flight made this landing a particularly hard test: Space-X said in advance that due to the high orbit of the mission's destination, the first stage booster would "subject to extreme velocities and re-entry heating, making a successful landing challenging."

The firm has a full roster of future missions, with 11 more scheduled this year alone, and will have no shortage of opportunities to practice the recovery. SpaceX has not yet begun reusing the recovered stages, but CEO Elon Musk says that it will probably conduct a first flight with one of the second-hand boosters this fall. In a news conference earlier this year, Musk set a high bar for the program, telling the crowd that "we'll be successful when it's boring" – rocket flight and rocket recovery as a matter of routine.