Stratolaunch And OSC

Stewart Money has some thoughts on the implications of the culmination of the courtship.

I’ve never really believed that the true goal of this program was a significant cost reduction. I think that the only requirement for which it makes sense is rapid-response single-orbit rendezvous.

But one other point that Stewart doesn’t mention. In the original rollout, they declared that the goal was (at least eventually) human missions. I don’t know how many people are going to be willing to go to orbit on a two-stage solid, particularly given OSC’s record. I know that I wouldn’t be, particularly given the more attractive alternatives (SpaceX/Dragon and perhaps whatever XCOR eventually comes up with). I wonder if this is the final nail in the coffin of the original cover story.

32 thoughts on “Stratolaunch And OSC”

  1. Just yesterday you linked to Clark Lindsey’s reusable Falcon 9 first stage article that explained how SpaceX was taking step-by-step approach to development, I suspect that Stratolaunch would have preferred a partner with a vehicle more suited to manned missions, but OSC is what they’ve got. Maybe once the system is actually flying we’ll see the sort of evolution SpaceX is working on.

  2. One thing to keep in mind is that OSC will be developing the first space launcher for Stratolaunch, not necessarily the only one. As such, getting to initial capability as soon as possible for as little investment as possible makes sense, and making the first two stages solids fits with this. High recurring costs, yes, but low up-front costs. The third liquid stage also fits with this – I’d be amazed if it doesn’t end up being closely related to the Antares/Cygnus liquid top stage, and thus already mostly engineered and paid for.

    Solids plus a storable-liquids vernier stage also make sense for the rapid-response mission you postulate, FWIW. Rapid response is indeed a logical explanation for developing the huge carrier aircraft in the first place. But never underestimate the possibility that a major reason it’s being built is that Burt just really really really wants to build it.

    1. Did you read what you linked to?

      However, the configuration revealed in December to meet the Paul Allen Stratolaunch requirement is not my design. About 10 years ago, to encourage innovation and design responsibility among the young engineers at Scaled, I took on the status of design advisor, while the title of Principal Configuration Designer went to a very talented team of designers, including Jim Tighe, Cory Bird, Bob Morgan and others. Except for the Bipod roadable aircraft, all the airplanes designed at Scaled after SpaceShipOne were not Burt Rutan designs.


      Q. We must ask: Is Stratolaunch at least partly an excuse to build the world’s biggest airplane?

      A. It would be nice to not have to build the world’s largest airplane to do the Stratolaunch mission. I do not look at it an excuse.

  3. Yeah, sure, Burt would say that. But you have to ask yourself, who else might have sold Paul Allen on paying for it? “Chief Designer” is far from the only possible definition of building something.

  4. Regardless, “just showed up for the press conference” seriously understates Burt’s role in the beast coming to be. Just sayin’.

      1. WTF Andrew? I’m just telling Henry that his speculation that Rutan just wants to build a really big airplane is both wrong and counter to Rutan’s explicit statements on that matter. Burt is retired by his own choice.

        1. 🙂

          I think you were nit-picking with your responses to my 1:45 pm and Henry’s 5:01 pm.

          But no malice, probably just a slow day.

        2. Trent. So, you’re saying categorically that Burt *doesn’t* want to build a really big airplane. Cool. Trent’s a long-range mind-reader!

          But seriously. True, he’s retired. From Scaled. Not from the Stratolaunch board of directors, however.

          And it’s been my experience that the decision to invest in major space launch systems just about always involves some non-rational elements, which the deciders then just about always deny. (Except for Elon – he’s honest, he’s scaring the pants off the rest of the world’s launch providers because he wants to go to Mars.) I suspect you understand this just fine though, and you’re just failing to take Burt’s denials with a grain of salt because you’re having fun with a contrarian position here. Heh. Nothing wrong with having fun!

  5. These solid stages could also to GEO, and plane could launch at equator.
    Though 1/2 of Falcon 9 payload to LEO, it could closer to meeting a Falcon GEO payload.

    And Stratolaunch more of mobile launchpad. Btw, anyone know the what rules restrict it from launching foreign rockets from their country?

    It seems that Stratolaunch can launch payloads to space. And solids are
    safer and apparently available as use for the Stratolaunch.
    Many years will Stratolaunch operational? Due lack of flights per year [unlike commercial airliner] could be around longer than the B-52s

  6. It’s hard for me to image Stratolaunch as anything except a 21st century “Glomar Explorer.” Howard Hughes’s original claim that he was building a ship for mining manganese on the sea floor secretly became the most ambitious covert operation of the Cold War: the attempted retrieval of a sunken Soviet submarine from extreme depths in the Pacific ocean. In the same vein, my gut tells me that the true motivations behind Stratolaunch will not be disclosed for years, and it probably should remain that way.

    Air launch has plenty of benefits, although it’s debatable whether avoiding weather, picking up ~0.8 mach initial speed for free, and avoiding the drag from the first 40k feet of atmosphere can justify the development costs of the world’s largest aircraft. But air launch gives the satellite operators great flexibility in choosing a satellite orbit that ground launch can never give. The aircraft can fly to a location with no azimuth restrictions, and it can fly to equatorial latitudes that can’t be reached from the Cape, Wallops, etc.

    Whoever needs this all-azimuth launch capability can certainly justify paying for the development of the world’s largest aircraft.

    1. Rand likes the “Glomar” theory because it’s a logical explanation, but as I’ve been saying, assuming rocket investment decisions are always 100% logical isn’t always the best match for the real world.

      Then too, there’s a lot of middle ground possible between “huge airplanes are COOL” and “Glomar Explorer II”. There may be other equally logical explanations. It’s been my experience that rocket entrepreneurs NEVER tell you everything about their business plans. I’d be quite surprised if it doesn’t turn out that Stratolaunch has specific markets in mind where their approach gives them an advantage. Whether they’re right about that, well, we’ll see.

  7. Thought.

    Wonder if you could hang a Minuteman III off that thing…..

    Shades of Space Vector…

    1. That carrier would be overkill for a single Minuteman ICBM.

      How about a rotary launcher loaded with say six Midgetman type missiles?

      Half B-52, Half Submarine.

  8. That’s crazy talk CFE! Next thing you’ll be suggesting that is also provides for ballistic trajectories that differentiate themselves from our ICBM’s and Sub based nukes in a way that potential adversaries will not mistake as a first strike nuke attack against them. What type of militarized payload makes sense on an EELV class rocket? Tungsten rods or something?

    1. I am not, in any way, suggesting that Stratolaunch will be used for suborbital weapons delivery. Putting suborbital weapons on this massive flying beast makes zero sense. All Stratolaunch missions will be orbital in nature. But DoD would have plenty of interest in an all-azimuth, all-inclination launch capability. It definitely meshes with the “Responsive Space” paradigm of launching satellites on short notice with orbits tailored for a very specific mission. Using solid-fuel rockets from OSC makes this even more likely, since they can be stored far easier than liquid-fueled SpaceX boosters could.

      1. The military has a strong interest in a rapid response launch capability. Currently, it takes months to stack a booster, integrate the payload with the rocket, roll it out and launch it. Space Command actually starts the process of booster selection and budget allocation years in advance of a launch. They want something that you can integrate and launch in less than a week.

        Stratolaunch and this rocket make for more than a microsat launcher. It could carry a variety of different payloads for mission augmentation or emergency replacement. Think ISR, GPS or comsat payloads launched in a hurry without launch pad or range constraints.

        1. The military has a strong interest in a rapid response launch capability.

          “Intended payload capability is 13,500 lbs. into low Earth orbit with first launch date target of 2018.”

          Boeing X-37B:
          Length: 29 ft 3 in (8.9 m)
          Wingspan: 14 ft 11 in (4.5 m)
          Height: 9 ft 6 in (2.9 m)
          Loaded weight: 11,000 lb (4,990 kg) (not counting fairing and mating hardware)

  9. Does it really matter what the carried rocket is? So long as it can be lifted by the launcher, and doesn’t screw up the weight and balance, and you have a good ignition system, could you not hang anyone’s rocket on the “bomb” rack?

    So ok the first launch is a safe though outmoded solid. I’d do that myself just to remove unknowns and complications from the first attempts. You learn a lot as well.

    The first rocket doesn’t have to be the only kind of rocket.

    Maybe it matters – willing t be convinced.

    1. Rockets with one or more cryo liquid propellants would complicate matters. You’d need to allow for boiloff during the climb to launch altitude, load extra propellant and/or insulate really well. And for longer flights to launch from a specific latitude, you might need to arrange to carry extra on the carrier aircraft and top up before launch.

      Solids and/or storable liquids really do simplify airlaunch.

      1. Personally, if I were going to air launch a liquid fueled rocket, I’d carry the propellant in the twin fuselages and fill the rocket in flight. There’s plenty of volume inside each of those otherwise empty fuselages – LOX in one and fuel (keroscene or LH) in the other.

        A liquid fueled rocket hanging beneath the aircraft is a honking big bomb that would make a takeoff accident decidedly unpleasant. Well, to be honest, having the propellant inside the fuselages wouldn’t be very nice in an accident, either. Still, you could jettison the empty rocket in a hurry if need be and dump the propellants fairly quickly. All of this would complicate the rocket’s interfaces with the aircraft but perhaps not excessively so.

        1. Personally, if I were going to air launch a liquid fueled rocket, I’d carry the propellant in the twin fuselages and fill the rocket in flight. There’s plenty of volume inside each of those otherwise empty fuselages –LOX in one and fuel (keroscene or LH) in the other.

          Yes to topping off cryo propellent in flight, the: “LOX in one and fuel (keroscene or LH) in the other” bit wouldn’t work unless the oxidiser and fuel had a similar mass

          1. That’s a good point but it could be addressed by arranging the tanks to have a roughly equal mass in both fuselages.

          2. fairly trivial, lets say the left side weighs 3X the right side, put tanks with water in the right side, as you pump into the rocket,
            dump the water.

            if the fuselage has the width, put the heavy tank towards the center and put the light tank as far outboard as you can.

            There are more complex things with offsetting the fuselages or twisting the wing roots a bit, but the water trick is brutal and simple.

      2. Makes sense, Henry. Still, as I say, the first kind of rocket launched doesn’t have to be the only kind ever launched. I’m not sure I’d conclude that only solids will fly from this contraption because the first rocket is a solid.

        Also, I wonder if there’s any thought to taking off with a liquid fueled rocket with empty tanks and then fueling it via air to air. Would have to wonder if the cryos can remain cryos through that transfer. Though kerosene would work.

        Still, you have weight and balance problems with a system like that.

  10. I don’t know what’s contrary about taking Rutan’s words as written.

    As for Rand’s theory, obviously there has to be some fantastic secret agenda because it couldn’t be that Allen and Rutan are just not that good at launch.

  11. This is one of the most bizarre undertakings in the history of non-governmental space, if that in fact is what it is. Everything about it has been slightly off, beginning with the initial news conference and Mike Griffin’s tepid “endorsement” of the very concept of air launch. Some of the technical specifications that floated around made no sense (the wing thickness ratio didn’t match the cruise Mach number, for example, by an amount that was glaring). And the challenges of adapting a liquid propellant rocket designed for vertical launch to horizontal carriage and launch were obvious to anyone with a few years’ experience in the field.

    Switching to a solid at this point is almost as bizarre. There is no existing motor large enough to serve as the first stage of a vehicle with Delta II capacity. Three Castor 120s side-by-side would do it, with a Castor 120 second stage and Castor 30 third stage. It would be anything but cheap. And developing new solids of optimal size is a huge, expensive undertaking.

    But a lot of money continues to be spent on it, apparently, so there must be some very strong motivation. The Glomar Explorer simile was the first thing that occurred to me the minute Mike Griffin opened his mouth at the kickoff presser. But I can’t think of an application for it, other than perhaps dropping the world’s largest conventional bomb on an Iranian nuclear weapon production facility. One could build a 100,000 pound steel penetrator shell, and still have 300,000 pounds of play room for high explosive…

  12. Why is it so difficult to accept that this may simply be the private-sector equivalent of the SLS; a technically suboptimal system where the personal interests of the people running the show are driving the design decisions?

    Paul Allen wants to build a orbital launch system. Paul Allen doesn’t really know anything about spaceships, and he only has one name in his rolodex under “Spaceship Builders I Know and Trust”. Bert Rutan is really a retired airplane builder, but he’ll come partially out of retirement to supervise a project like this. Being technically competent, he knows that an orbital launcher will be Mostly Not An Airplane, but it can be party an airplane.

    And, regardless of the details of the mission requirements, this launcher will include the greatest possible airplane-like contribution, and the parts of the system which are not airplane-like will be as technically conservative as possible. Because if they aren’t, there will be little Bert Rutan can contribute. And if Bert Rutan isn’t visibly on top of things, particularly the technically challenging parts, Paul Allen will start worrying that his gigabucks are disappearing into an incomprehensible morass run by people he doesn’t know but with decades of experience in generating cost overruns and schedule slips.

    If you honestly want first-orbit rendezvous, you do a Falcon 9 launch with a plane change at insertion. That gets you six tons to the exact LEO you want, including phasing and rendezvous, in sixty minutes or less with existing technology. If you want launch of any sort with Bert Rutan at the (perhaps mostly symbolic) apex of the pyramid, you need birdzilla.

    1. Are you deliberately misspelling Burt’s name to make an ironic point about genius secret agendas vs simple biased naivety?

      Because that’d be pretty cool.

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