SpaceX Mini-BFS will make fully reusable Falcon 9 and Falcon Heavy in 2019

Elon Musk tweeted that SpaceX will make a mini-Big Falcon Spaceship upper stage for the Falcon 9.

They are aiming for an orbital flight by June 2019.

The MVac will have too high TWR and have flow separation at sea level. It will practice and testthe reentry regime. Elon said it won’t land propulsively for those reasons.

Mini-BFS will have an ultra-light heat shield and high Mach control surfaces. Those are things that SpaceX cannot test well without orbital entry. SpaceX has confidence in propulsive landings.

SpaceX is building a BFR development ship to do supersonic through landing tests in Boca Chica, Texas.

49 thoughts on “SpaceX Mini-BFS will make fully reusable Falcon 9 and Falcon Heavy in 2019”

  1. I don’t get why the mini BFR has to use ballutes and/or balloon landing. From the examples of the X-37 and Skylon you could use short, stubby wings that would add minimally to the dry weight, unlike the large shuttle wings, but allow a full aircraft like landing.

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  2. This makes sense. Otherwise you would have to wait for BFR to be completed before you could test BFS. It is also cheaper and faster to produce a smaller test article for aerodynamic testing and landing tests. This way BFS and BFR development happens at the same time. SpaceX wouldn’t do it any other way.

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  3. BFS will have landing legs and control surfaces, Tom. Absolutely correct.They *will* test landings of BFS.They will *not* test landings on the Falcon 9 upper stage. Their testing objectives are all about a new-fangled way to slow the craft down in the upper atmosphere from orbital speeds. They want to test stuff that hasn’t been tested before – heat shielding, winglets and maybe liquid methane-liquid oxygen propulsion using nozzles that will hopefully work at sea level *and* in the upper atmosphere.When the BFS test articles are ready, they’ll test landings, too – but they won’t bother with landings for the Falcon 9 upper stage. They don’t need the test data for that; if anyone knows how to land a rocket, it’s SpaceX. Reserving fuel for landings and adding weight for low-speed control surfaces and landing legs would cut deeply into their paying payloads. That isn’t in the plan, and it doesn’t need to be in the plan.

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  4. That’s not the point. The point is to test the BFS design in a smaller cheaper version. And yeah they do need to test landings on it. BFS is what will be landing and it has legs and control surfaces.

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  5. This makes sense. Otherwise you would have to wait for BFR to be completed before you could test BFS. It is also cheaper and faster to produce a smaller test article for aerodynamic testing and landing tests. This way BFS and BFR development happens at the same time. SpaceX wouldn’t do it any other way.

    Reply
  6. BFS will have landing legs and control surfaces, Tom. Absolutely correct.

    They *will* test landings of BFS.

    They will *not* test landings on the Falcon 9 upper stage. Their testing objectives are all about a new-fangled way to slow the craft down in the upper atmosphere from orbital speeds. They want to test stuff that hasn’t been tested before – heat shielding, winglets and maybe liquid methane-liquid oxygen propulsion using nozzles that will hopefully work at sea level *and* in the upper atmosphere.

    When the BFS test articles are ready, they’ll test landings, too – but they won’t bother with landings for the Falcon 9 upper stage. They don’t need the test data for that; if anyone knows how to land a rocket, it’s SpaceX. Reserving fuel for landings and adding weight for low-speed control surfaces and landing legs would cut deeply into their paying payloads. That isn’t in the plan, and it doesn’t need to be in the plan.

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  7. That’s not the point. The point is to test the BFS design in a smaller cheaper version. And yeah they do need to test landings on it. BFS is what will be landing and it has legs and control surfaces.

    Reply
  8. This makes sense. Otherwise you would have to wait for BFR to be completed before you could test BFS. It is also cheaper and faster to produce a smaller test article for aerodynamic testing and landing tests. This way BFS and BFR development happens at the same time. SpaceX wouldn’t do it any other way.

    Reply
  9. I don’t get why the mini BFR has to use ballutes and/or balloon landing. From the examples of the X-37 and Skylon you could use short, stubby wings that would add minimally to the dry weight, unlike the large shuttle wings, but allow a full aircraft like landing.

    Reply
  10. I don’t get why the mini BFR has to use ballutes and/or balloon landing. From the examples of the X-37 and Skylon you could use short, stubby wings that would add minimally to the dry weight, unlike the large shuttle wings, but allow a full aircraft like landing.

    Reply
  11. No. The BFR is supposed to have a 9m diameter fuselage; the Falcon series have 3.66m diameters. There is NO WAY to put an actual BFR or BFS stage onto a Falcon. Trying would be a waste of money; SpaceX is going to build a sub-scale model that actually fit onto a Falcon, and test that.

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  12. You mean like how the Senate will retaliate by subpeonaing Dem congresscritters who leaked classified information? And Maxine Water’s husband and his apparentl shady involvement with a bank?And four newly elected Dem congresscritters who have assault on women accusations going on?ALL of which can lead to prosecutions, as Trump controls the DoJ. That won’t be the case with Nutjob Nancy’s BS.Last but not least…Comey went on TV and SAID Shrillary broke the law but he wouldn’t recommend prosecution at that time. Well, that leaves the door open to still prosecute her. That will probably be the NUCLEAR option if the Dems still want to escalate their little game of Constitutional Hardball.Oh yeah. Criminal liars WILL be subpeonaied, Urgelt.

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  13. I doubt NBF is drawing the right conclusion here.The headline reads, “SpaceX Mini-BFS will make fully reusable Falcon 9 and Falcon Heavy in 2019.”But Musk has said that SpaceX doesn’t need more experience with reusable landings right now. What they need is experience with control surfaces and heat protection during orbital reentries. They’d like to get some experience with liquid methane/liquid oxygen engines tuned to work either at sea level or in near-vacuum, too.Recovery does not appear to be SpaceX’s goal for the Falcon 9 second stage.To recover the second stage would require a *lot* more engineering. They’ll need landing legs. They’ll need *additional* control surfaces for low-speed control – the winglets are for high-speed control, they won’t work on a vertical tail-first recovery. All of that will add weight, on top of the winglets and heat shielding.Meanwhile they will still have launch missions to perform. If they have to reserve fuel on the second stage for recovery, that will reduce payload for those missions. The added weight to configure the second stage for recovery will also eat into payload.I don’t see it. All I see is what Musk said: SpaceX wants to do some testing of engineering concepts intended for use on BFR. I don’t expect any attempt to recover second stages at this time. BFR will be the first fully-reusable launch system – which is what Musk has been saying all along.

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  14. The BFR is supposed to be build to the same specifications and rocket configurations as the heavy Falcon, so that eliminates most of what you are saying.

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  15. I wonder if they’ll use an FH to get to trans-lunar and/or interplanetary specific energies. If you assume that the mini-BFS will be about 5000 kg (a tonne heavier than a regular S2), then a 3-stick-reusable FH will have more than 6500 m/s of delta-v available in LEO. That’s more than enough to do a free-return trajectory around the Moon to test TEI reentry. And there are likely depressed trajectories that would accelerate enough to test a trans-Mars reentry as well.

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  16. Right. We have re-entered lots of capsules, and the Space Shuttle, but not something shaped like the BFS. A ~40% scale model made from a Falcon 9 2nd stage would be close enough to try out the aeroheating, lift and drag characteristics, etc.More importantly, it can be used to calibrate their computer simulations for the full-size spaceship. If the simulations can predict how the scale model behaves, then they will likely predict the full-size BFS too.There are no wind tunnels big enough and fast enough to test this stuff out. The only way is by actually flying through the atmosphere. The same is true for hypersonic air-breathing engines. They launch them on a rocket to test them out in sub-scale versions.

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  17. “Recoverable” and “reusable” are two different things. My guess is that they’ll use chutes to get it to float, so they can finish up their engineering studies.

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  18. No. The BFR is supposed to have a 9m diameter fuselage; the Falcon series have 3.66m diameters. There is NO WAY to put an actual BFR or BFS stage onto a Falcon. Trying would be a waste of money; SpaceX is going to build a sub-scale model that actually fit onto a Falcon, and test that.

    Reply
  19. Not necessarily, It could mean that they plan a low tech way like parachutes.I imagine they would want to study the vehicle intact to determinewhat design changes would be needed in the full version and maybe eventest the reusability of the test vehicle.

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  20. Yeah, this is a test version, not a production model. I wouldn’t expect to get anything besides data on the BFS shape, handling at orbital speeds on reentry, etc.

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  21. Because it wouldn’t get off the ground? Because putting the “final size BFS” on a Falcon 9H core booster (Falcon 9) would probably crush it? Because the diameter of the BFS is much greater than the Falcon Heavy core booster (Falcon 9) and there is no adapter that would mate the two systems? Because such a configuration would break apart either before or certainly during Max Q?

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  22. You mean like how the Senate will retaliate by subpeonaing Dem congresscritters who leaked classified information? And Maxine Water’s husband and his apparentl shady involvement with a bank?

    And four newly elected Dem congresscritters who have assault on women accusations going on?

    ALL of which can lead to prosecutions, as Trump controls the DoJ. That won’t be the case with Nutjob Nancy’s BS.

    Last but not least…Comey went on TV and SAID Shrillary broke the law but he wouldn’t recommend prosecution at that time. Well, that leaves the door open to still prosecute her. That will probably be the NUCLEAR option if the Dems still want to escalate their little game of Constitutional Hardball.

    Oh yeah. Criminal liars WILL be subpeonaied, Urgelt.

    Reply
  23. I doubt NBF is drawing the right conclusion here.

    The headline reads, “SpaceX Mini-BFS will make fully reusable Falcon 9 and Falcon Heavy in 2019.”

    But Musk has said that SpaceX doesn’t need more experience with reusable landings right now. What they need is experience with control surfaces and heat protection during orbital reentries. They’d like to get some experience with liquid methane/liquid oxygen engines tuned to work either at sea level or in near-vacuum, too.

    Recovery does not appear to be SpaceX’s goal for the Falcon 9 second stage.

    To recover the second stage would require a *lot* more engineering. They’ll need landing legs. They’ll need *additional* control surfaces for low-speed control – the winglets are for high-speed control, they won’t work on a vertical tail-first recovery. All of that will add weight, on top of the winglets and heat shielding.

    Meanwhile they will still have launch missions to perform. If they have to reserve fuel on the second stage for recovery, that will reduce payload for those missions. The added weight to configure the second stage for recovery will also eat into payload.

    I don’t see it. All I see is what Musk said: SpaceX wants to do some testing of engineering concepts intended for use on BFR. I don’t expect any attempt to recover second stages at this time. BFR will be the first fully-reusable launch system – which is what Musk has been saying all along.

    Reply
  24. I wonder if they’ll use an FH to get to trans-lunar and/or interplanetary specific energies. If you assume that the mini-BFS will be about 5000 kg (a tonne heavier than a regular S2), then a 3-stick-reusable FH will have more than 6500 m/s of delta-v available in LEO. That’s more than enough to do a free-return trajectory around the Moon to test TEI reentry. And there are likely depressed trajectories that would accelerate enough to test a trans-Mars reentry as well.

    Reply
  25. Right. We have re-entered lots of capsules, and the Space Shuttle, but not something shaped like the BFS. A ~40% scale model made from a Falcon 9 2nd stage would be close enough to try out the aeroheating, lift and drag characteristics, etc.

    More importantly, it can be used to calibrate their computer simulations for the full-size spaceship. If the simulations can predict how the scale model behaves, then they will likely predict the full-size BFS too.

    There are no wind tunnels big enough and fast enough to test this stuff out. The only way is by actually flying through the atmosphere. The same is true for hypersonic air-breathing engines. They launch them on a rocket to test them out in sub-scale versions.

    Reply
  26. I agree, it seems like SpaceX is going to use a Falcon Heavy second stage as a scale model of a BFS. This makes a lot more sense than to turn Falcon Heavy into a mini-BFS, since their business model seems to be one rocket to lift them all so costs are kept down. Suddenly having two rocket lines going forward goes against that stated policy.

    Reply
  27. No, SpaceX does not plan to reuse the Falcon 9 upper stage. Gwynne Shotwell made this clear a while ago. Her exact words:”On missions with extra propellant, we want to bring it back to see how it behaves, not to recover or reuse. This data will be very valuable. “

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  28. Not necessarily,
    It could mean that they plan a low tech way like parachutes.
    I imagine they would want to study the vehicle intact to determine
    what design changes would be needed in the full version and maybe even
    test the reusability of the test vehicle.

    Reply
  29. Because it wouldn’t get off the ground? Because putting the “final size BFS” on a Falcon 9H core booster (Falcon 9) would probably crush it? Because the diameter of the BFS is much greater than the Falcon Heavy core booster (Falcon 9) and there is no adapter that would mate the two systems? Because such a configuration would break apart either before or certainly during Max Q?

    Reply
  30. If you tried entering a link, they don’t go through with this chat system and are instead deleted. Instead, try taking out some of the slashes/periods in the address so it can stay and we can add them back in to search it.

    Reply
  31. “SpaceX Mini-BFS will make fully reusable Falcon 9 and Falcon Heavy in 2019″No, this is incorrect. In the Twitter thread, Musk says that they’re not going to land it propulsively, which is pretty much the saying that it’s an expendable test article.If they could figure out how to put 52 Starlinks (one full plane plus spares) into a fairing on an FH, that would be pretty useful to them, even if it were expendable. And I suppose that this could turn into that. But I doubt it.

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  32. This looks like a scaled down model for testing BFS’s aerodynamic surfaces. An intermediary step before full scale sub-orbital and the final orbital tests.I think this is different from a reusable 2nd stage and capsule, more like fusing a second stage and fairing into a single BFS-like body, with heatshield, winglets, etc., with a strong payload penalty.Which won’t be a problem if what you want to test is the shape and behavior of the vehicle during re-entry.

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  33. I agree, it seems like SpaceX is going to use a Falcon Heavy second stage as a scale model of a BFS. This makes a lot more sense than to turn Falcon Heavy into a mini-BFS, since their business model seems to be one rocket to lift them all so costs are kept down. Suddenly having two rocket lines going forward goes against that stated policy.

    Reply
  34. No, SpaceX does not plan to reuse the Falcon 9 upper stage. Gwynne Shotwell made this clear a while ago. Her exact words:
    “On missions with extra propellant, we want to bring it back to see how it behaves, not to recover or reuse. This data will be very valuable. “

    Reply
  35. If you tried entering a link, they don’t go through with this chat system and are instead deleted. Instead, try taking out some of the slashes/periods in the address so it can stay and we can add them back in to search it.

    Reply
  36. “SpaceX Mini-BFS will make fully reusable Falcon 9 and Falcon Heavy in 2019”

    No, this is incorrect. In the Twitter thread, Musk says that they’re not going to land it propulsively, which is pretty much the saying that it’s an expendable test article.

    If they could figure out how to put 52 Starlinks (one full plane plus spares) into a fairing on an FH, that would be pretty useful to them, even if it were expendable. And I suppose that this could turn into that. But I doubt it.

    Reply
  37. This looks like a scaled down model for testing BFS’s aerodynamic surfaces. An intermediary step before full scale sub-orbital and the final orbital tests.

    I think this is different from a reusable 2nd stage and capsule, more like fusing a second stage and fairing into a single BFS-like body, with heatshield, winglets, etc., with a strong payload penalty.

    Which won’t be a problem if what you want to test is the shape and behavior of the vehicle during re-entry.

    Reply

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