The next launch of the Falcon 9 rocket its creators
запланировали something very special: an attempt to fit the first step on a floating platform. Platform dimensions are approximately 90 meters long and 30 meters wide without additional side platforms and a little more than 50 meters from them. It is worth remembering that the scope of the rocket landing gear is about 21 meters.
Thus, if in the case of a previous run of required precision landing within 10 kilometers, but now for a successful landing on the platform launcher maximum error should not exceed about 10 meters. The situation is complicated by the fact that the platform will nezayakorena and, despite its ability to adjust its location, a small drift yet completely rule will not work.
Return Procedure stage will begin immediately after its separation. The engines will be restarted three times: first launch is designed to adjust the trajectory of the input stage to the atmosphere, the second - to reduce the rate of descent to 1,300 meters per second to 250, and finally, the third launch will happen just before landing to further reduce the speed of a few meters per second.
For more accuracy should provide four already proven previously independently controlled steering latticed stage.
SpaceX estimates the chance of success is low: less than 50%, provided that the events will develop under the optimistic scenario. However, even if the plant level will not be able to be collected invaluable for further work on a reusable launch vehicle data. Altogether SpaceX planned for next year yet at least a dozen starts and they believe that this amount would be sufficient not only to practice landing, but also to attempt to re-launch stage who returned successfully.
Source:
geektimes.ru/post/243077/