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posted by janrinok on Wednesday March 14 2018, @03:51PM   Printer-friendly
from the busy-little-rockets dept.

SpaceX will attempt to launch five Falcon 9 rockets in April. This includes an International Space Station (ISS) resupply mission and a mission to launch Bangabandhu-1, Bangladesh's first satellite. The Bangabandhu-1 launch is planned to be the first to use SpaceX's Falcon 9 Block 5 rocket, which may be the final major iteration of Falcon 9 before replacement by BFR.

At a South by Southwest (SXSW) panel, Elon Musk said that SpaceX could test the Big Falcon Rocket (BFR) "spaceship" as soon as the first half of 2019. The spaceship is the second stage of the complete BFR rocket, would be capable of reaching orbit without the first stage booster, and alone has over 50% more thrust than an entire Falcon 9.

The initial tests would likely be similar to the Grasshopper vertical takeoff and landing tests.

Also at USA Today, MarketWatch, and SpaceNews.


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  • (Score: 3, Informative) by takyon on Wednesday March 14 2018, @10:01PM (1 child)

    by takyon (881) <reversethis-{gro ... s} {ta} {noykat}> on Wednesday March 14 2018, @10:01PM (#652627) Journal

    https://www.reddit.com/r/space/comments/76e79c/i_am_elon_musk_ask_me_anything_about_bfr/dodec8l [reddit.com]

    Will be starting with a full-scale Ship doing short hops of a few hundred kilometers altitude and lateral distance. Those are fairly easy on the vehicle, as no heat shield is needed, we can have a large amount of reserve propellant and don't need the high area ratio, deep space Raptor engines.

    Next step will be doing orbital velocity Ship flights, which will need all of the above. Worth noting that BFS is capable of reaching orbit by itself with low payload, but having the BF Booster increases payload by more than an order of magnitude. Earth is the wrong planet for single stage to orbit. No problemo on Mars.

    BFS without booster can do point-to-point suborbital "airline" flights, and it can apparently get into orbit, albeit with a small payload and possibly worse $/kg than the complete rocket with booster.

    Looking at the Falcon 9 and BFS numbers:

    https://en.wikipedia.org/wiki/BFR_(rocket) [wikipedia.org]

    Empty mass: 85,000 kg (187,000 lb)
    Gross mass: 1,335,000 kg (2,943,000 lb)
    Engines: 7 × Raptor (4 × vacuum, 3 × sea level)
    Thrust: 12.7 MN (2,900,000 lbf) total

    https://en.wikipedia.org/wiki/Falcon_9 [wikipedia.org]

    Mass: 549,054 kg (1,210,457 lb)
    First stage thrust: FT (late 2016): 7,607 kN (Block 5 is 7-8% percent higher)
    Second stage thrust: FT: 934 kN

    The Raptor rocket engine [wikipedia.org] has 2-3 times the thrust of the Merlin 1D.

    So the BFS, which is a "second stage", has over 12 times the thrust of the Falcon 9 second stage, and over 50% more than the complete Falcon 9 Block 5.

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  • (Score: 2) by Immerman on Wednesday March 14 2018, @10:46PM

    by Immerman (3985) on Wednesday March 14 2018, @10:46PM (#652649)

    Thanks, nice to hear it straight from the horse's mouth. I hope he can pull it off.

    A 27% reduction in propellant per ton would still be quite impressive though.

    Oh, and FYI the Wikipedia page you linked is still is still describing the original interplanetary BFR, not the new, smaller design with only two atmospheric engines.

    Also, it might not be a good idea to use those vacuum engines in an atmosphere - it sounds like using rocket bells optimized for less than ~40% of ambient pressure will result in flow separation, which can cause bell damage or control difficulties.