• Jeff Smith

    Just about the smartest thing they can do to reduce risk.

  • Andrew Tubbiolo

    Called this one two years ago.

  • ReSpaceAge

    I doubt they will perfect this mini shuttle before building BFS. Sounds more like they will be testing many different technologies both for BFS and for a practical recoverable “second stage”

    Two fully reusable space vehicles for the testing price of one.

  • Andrew Tubbiolo

    This is just the beginning of the long development cycle of the BFS. It won’t go fast.

  • Smokey_the_Bear

    Not a fan.
    He’s putting too much on the plate. He needs to have his people working on Dragon 2, and the BFR, no other new spaceship distractions.

  • ReSpaceAge

    2024 Mars window is the target. We shall see.

  • Andrew Tubbiolo

    I’ll bet Musk agrees with you, that’s why I bet his BFS people are working on SFS. Because SFS is probably viewed as a a needed stepping stone to BFS. Serial development, not parallel. My conjecture is they hit a stumbling block and need an x-vehicle to show the way. I’ll conjecture further and guess that they don’t believe the CFD of the BFR and need SFS to nail down the CFD.

  • Jeff Smith

    I think this announcement effectively means 2024 is off the table. If they realized they need a subscale vehicle to anchor aerothermal models, etc., then this won’t be done in parallel – it’ll be serial.

  • duheagle

    This wouldn’t be a distraction from BFR as it is probably much nearer completion. SpaceX, recall, got USAF money some time ago toward an F9/H Raptorized 2nd stage. I think this announcement is it. It has doubtless been proceeding in parallel with BFR work and may even have involved some of the same folks on the SpaceX engineering staff. Now that the BFR design has narrowed toward a Mark I form, a “Mini-Me” upper stage can be more quickly produced in all-up trim. The USAF may well have some as-yet-still-classified payload(s) in mind for this unit, but I think its bread-and-butter job is going to be Starlink deployments. Doing these with a completely reusable F9/H configuration would reduce SpaceX’s internal costs of deployment significantly.

  • duheagle

    That seems pretty far-fetched to me. BFR’s shapes are not at all complex so I don’t see where CFD calibration would be any kind of issue at all. Both SpaceX and Blue Origin seem to have done a lot of ground-breaking CFD work already aimed at far more complex issues, such as what goes on inside turbomachinery. That would be comparable to playing a symphony. CFD-ing the mold line of BFR is, in comparison,like playing scales.

    I think “SFS,” as you very aptly dub it, was developed for two reasons:

    1) USAF wanted it for a reason or reasons that will probably only become clear in future, and

    2) SpaceX can benefit very considerably by using it as part of a completely reusable system to loft its Starlink birds. A more powerful, capacious and completely reusable upper stage for FH would also likely see that vehicle equal or surpass both Blue’s New Glenn and SLS Block 1 in terms of both LEO lift and reusability.

  • duheagle

    I would say, “no,” “possibly” and “yes,” respectively. I suspect SFS will fly to orbit within six months.

  • duheagle

    The world seems to be full of people who lost past bets against SpaceX’s ability to walk and chew gum at the same time. Don’t be a new one.

  • therealdmt

    I always thought it made sense to go ahead with the Air Force idea of a Raptor-powered upper stage on the Falcon Heavy (or Falcon 9) for 1) revenue generating flights that such a capability might garner, but also 2) to at the same time gain experience with the Raptor engines, methane fuel and composite fuel tanks.

    Such a Raptor-powered upper stage on the Falcon Heavy would also put more pressure on SLS in terms of closing the gap in the argument that SLS can send much more payload to beyond LEO destinations. Further, it would help close the looming performance gap with New Glenn, assuming NG development goes smoothly. Finally, developing a wider faring would also be useful in that vein.

    Looks like they’re going even further in the prepping for BFR realm though, making a mini-BFS for the Falcon 9. I wonder if it will be built to carry humans (after initial testing)? Will it be operational, or just a test vehicle? Will it be able to carry cargo, and if so, how would it deploy? Will they use it to test in-orbit refueling (and what might they do with a re-fueled mini-BFS in orbit)?

    Very intriguing!

  • Andrew Tubbiolo

    I saw a twitter exchange on Reddit, and it seems my wild ass guess/conjecture was not far off at all. Check it out.

  • Michael Halpern

    I don’t think it will be raptor, all they need is a aerodynamic test article

  • therealdmt

    Dragon 2 is already in the home stretch, so they’re just looking ahead to what comes next, development-wise.

    Unfortunately, what comes next (BFR/BFS) is a giant leap beyond what has ever been done before by humanity, so this is just a recognition that an intermediate step is needed

  • therealdmt

    Hmm, after reading more of what Elon posted on Twitter about this, I’m thinking it might just be the in-orbit equivalent of the BFS-dev vehicle they’ll be doing hops/landing tests with in Texas.

    Elon: “Aiming for orbital flight by June”

    EDA: “”How will it propulsively land? The MVac would be too high TWR and have flow separation at sea level… or will this just be to practice the reentry regime?”

    Elon: “Won’t land propulsively for those reasons. Ultra light heat shield & high Mach control surfaces are what we can’t test well without orbital entry. I think we have a handle on propulsive landings.”

    EDA: “I think you have a handle on propulsively landing too. Will this little baby BFS be practicing the flip maneuver too from belly first to tail down?”

    Elon: “No, we’re building a BFR dev ship to do supersonic through landing tests in Boca Chica, Texas”

  • therealdmt

    Still, SpaceX has a clear history of getting as much as possible of their development work done on flights that customers have otherwise paid for. This “mini-BFS” (though Elon did write “mini-BFR”?) could yet be put to practical use.

    Lots to look forward to for next year

  • duheagle

    Doing a bit of digging, I see you may be right. Further details no doubt forthcoming.

  • duheagle

    Yes, I stand corrected. Subsequent Musk tweet reported on Space.com says, “”Ultra light heat shield & high Mach control surfaces are what we
    can’t test well without orbital entry.”

  • duheagle

    No, but it will be able to maneuver accurately in the atmosphere. I suspect these “SFS” upper stages will be recovered by Mr. Steven and his possible future clones.

  • duheagle

    As always, disagree anent schedule. This is all going to go at warp speed.

  • Michael Halpern

    Still if it is raptor powered it will be to compensate for the payload penalty, if SL raptor can compensate for it, rather than cost more,

  • Andrew Tubbiolo

    I have friends who did CFD, and they always said the CFD worked after wind tunnel runs or real world tests.

  • Andrew Tubbiolo

    Well, that’s noted. But I’m still waiting for those suborbital Dragon 2 tests where they test the crew escape system at Max Q, and at worst case ballistic reentry trajectory. We’re a few years late on that test series. If you remember Musk said those tests were a year or so off back in 2014. Space X is good, even great, but first flights have yet to happen on predicted dates. Next year is yet another bold launch date. I won’t think less of them when they miss it.

  • Andrew Tubbiolo

    Jeff’s online record is quite good. Most of his insights pan out in one form or another. I’d lose a lot of fat betting lunches against him.

  • Terry Stetler

    “But I’m still waiting for those suborbital Dragon 2 tests where they test the crew escape system at Max Q, and at worst case ballistic reentry trajectory.”

    Since they’re reusing the DM-1 uncrewed test flight vehicle for the IFA (In Flight Abort) test, it can’t happen until after the DM-1 launch. This been at the mercy of NASA paperwork and the ISS Visiting Vehicle schedule (HTV-7 had to leave first.)

  • Andrew Tubbiolo

    And you know what, those are good reasons. But that’s the crux of the point I’m trying to make about Space X and schedules. There’s always something. Space X is not immune to the same problems that the rest of the aerospace has. They do overcome those issues better than pretty much anyone else, but they still have to overcome them. That’s why I don’t believe Space X’s schedule claims. And it’s okay that they miss schedule, because in the end, they fly.

  • MzUnGu

    The GEO sat biz peaked a few years ago in 2014, so did small sat in 2015…add that 2 years build time, this is about when we have an excess capability of launchers…. not a good time to be spend your money on this kind of R&D in the sat and LV market.

  • Andrew Tubbiolo

    Before we did a full up STS Max Faget wanted to do a subscale 5 ton to LEO reusable shuttle to practice reusable space flight systems and operations with. He called it a DC-3. This SFS sounds like it could eventually become Faget’s subscale shuttle if it’s extended into a real service life. I think it’s the path to sanity and a BFS that works.

  • Tom Billings

    If SpaceX were in existence for nothing more than launching GEO satellites, that would be a useful statement. Since they are not so limited, it isn’t.

  • MzUnGu

    What else had they launched in any significant numbers?

  • Tom Billings

    It’s irrelevant what they have launched in the past. SpaceX is in existence to do things that the Cost+ Congressional Contractor’s Club *will*not* do. They are here to open the Solar System to the rest of us, which Congress would never fund, because there is no political majority behind it outside NASA Center districts. That apparently requires pre-flight tests that validate their design for a fully reusable launch vehicle, the BFR/BFS. This type of seconf stage is how they will do that. Perhaps they will also use FH with this stage to test things like Metha/LOX propellant loading on-orbit. We will see.

  • MzUnGu

    What will BFR launch to pay the engineers? if not geo-sats? Who is building the Moon-Sats or the Mars-Sat to pay them bills again? did you send in some extra cash to IRS/NASA or a check to Musk/SpaceX recently?

  • Tom Billings

    “did you send in some extra cash to IRS/NASA or a check to Musk/SpaceX recently?”

    Not I!

    ” What will BFR launch to pay the engineers? if not geo-sats?”

    The StarLink sats that will bring much revenue, once Musk gets that operation up to speed. Apparently some trouble there with his upper management in StarLink, but that is to be expected when some people resist changing corporate cultures from MicroSquish to SpaceX.

  • SamuelRoman13

    Kind of like Dream Chaser, but the 2nd stage will not drop off Like DC does.Or like the little image to left. Isn’t there a old Naval Air Station down there. I guess it has a long runway. Check Google I suppose. Some fun. Wonder if SSTO. Dragon 3.

  • SamuelRoman13
  • Michael Halpern

    I wonder if it will include fairings, if not then we could at least see cargo Dragon 2 riding on it

  • ThomasLMatula

    Solves the problem of recovering the farings and will lower the costs of deploying his Starlink system, so its a good move.

  • ThomasLMatula

    Yes, it appears the wanted to build the satellites the old way designed for the old ELV. The evidence would indicated they just couldn’t wrap their mind around the idea of mass production and designing satellites to be recovered and replaced as needed.

  • ThomasLMatula

    The could be a really good competitior for the X-37B. In the iterim they would work well to test communication and remote sensing technology for private firms. And then there is the micro-gravity research market he was focusing DragonLab on.

  • Michael Halpern

    Actually I suspect it will have the usual fairings, and reuse is just a secondary goal here, its primary purpose is testing, reuse if they can, but its also going to be LEO constrained most likely, my guess is that it will do a near full orbit before attempting to land on the opposite coast net boat, while the net boat at the launch coast gets the fairings, being LEO constrained limits potential launches to use to mostly CRS and a few others including Starlink

  • Michael Halpern

    No they have hinted at upper stage recovery tests with f9 for a while

  • Michael Halpern

    I don’t know, i think for practical reasons, it will not have the integrated fairings of BFS chomper, it is LEO constrained, meaning it will either have to launch a bunch of sats at once, or the payload will be Dragon,

  • therealdmt

    Max Faget — haven’t heard that name in a while! 🙂

  • Andrew Tubbiolo

    He had a lot of good, sane ideas WRT STS and ISS in the 70’s and 80’s.

  • Andrew Tubbiolo

    Was thinking about your points last night and came up with this. Disclaimer, it sounds to me that SX is developing a new stage/vehicle. Maybe they’re not. Perhaps they’re doing a miminal modification of a Falcon 9 2nd stage to test the aero-thermodynamics of re-entry. That’s a much smaller project. Or, per your point, about the USAF, perhaps this has been under development for some time and is only now coming out. Those are believable situations where anything like the announced time frame could happen.

  • Gerald Cecil

    They should be able to relatively quickly produce the correct BFS body shape(s) + mass moments + partial heat shield. They’d need RCS from Dragon and probably a parasail evolved from the earlier faring capture tests. None of this seems too complicated if they focus on a bare-bones engineering test object vs new operational vehicle.

  • duheagle

    The pace of Commercial Crew work has been artificially constrained by internal NASA infighting. SpaceX’s work for its own account suffers from no such source of drag.

  • duheagle

    If it has an integral cargo hold, ala BFR, then Dragon couldn’t ride in it as D2 could not use its escape system should something go pear-shaped on the way to orbit. And it’s hard to see how D2 could ride atop something that looks like a mini-BFR. I think D2 will operate with the current expendable 2nd stages until ISS is retired.