back to article DARPA: You didn't think we could make a Mach 6 spaceplane, so let us have this MACH TEN job

In this post-Space Shuttle world, it often seems that the dream of a spacecraft which could reach orbit without expensively throwing most of itself away is receding rather than drawing closer. Last time DARPA went for a spaceplane - the X-30 SSTO concept of 1984 Sure, there's the tiny X-37B "space warplane", carrying out …


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    1. TheOtherHobbes

      Nah. HMG are going to spunk £50bn on a train set, while turning down funding for Skylon because it's 'not cost effective.'

      Skylon should talk to Musk. They might not get along, but it would be fun to sit in on the meetings.

    2. John Smith 19 Gold badge

      "I really hope the UK gov decides to fund it soon"

      Already in the works, as described here

      And of course by El Reg.

  1. i like crisps

    'Unidentified Fibbing Object'

    Instead of messing around with rockets couldn't those nice people

    from DARPA just pop over to AREA 51 and borrow a couple of flying saucers

    for the weekend? I'm sure DARPA's tech's would be able to reverse-engineer

    the craft for their own benign purposes thus saving themselves and the

    American taxpayers ('us') a lot of time and expense...hows that for some

    'Blue Sky Thinking'?

  2. jonathan keith Silver badge


    An article about scramjets and no mention of lighting matches in hurricanes? I tell you, the quality of reporting here is going downhill rapidly. I may have to cancel my subscription.

  3. Anonymous Coward
    Anonymous Coward

    But surely gravity is the problem here. So reduce that to a much less or even negative and getting stuff into space is simple.

    (I'll leave creating an anti-gravity device as an exercise for the reader - is anyone researching if there is a way of creating artificial- / anti- gravity?).

    1. loneranger


  4. Rustident Spaceniak

    Why bother with a scramjet? And why worry about the thermal insulation?

    You only need a scramjet for this if you want maximum efficiency for maximum dollars. If "feasible and affordable" is the word, launch with a normal turbofan, go to Mach 3.5 or so with that at a reasonable altitude, and do the rest with a rocket. You can always play around with combined cycle a bit, inject some oxygen into the turbofan intake to get you as far as Mach 4 and maybe 50km up or so, but at the end of the day a rocket will do the job best - specially one fed from the same kerosene tank you've been using for that turbofan.

    Regarding the thermal insulation, you're talking about a Mach 10 re-entry, not Mach 28. That's a totally different league. Mach 10 can be done with quite solid, light ceramics as demonstrated by the German Shefex-II experiment last year.

  5. disgruntled yank Silver badge

    and why not

    the project name "Wretched XS-1"?

  6. SirDigalot
    Paris Hilton

    always confused about brain surgery

    for the longest time they chopped the skull cap off and randomly probed in areas they figured would be the bits that controlled stuff then made note of it.

    not saying they are not smart (chopping the skull off with a conscious patient I can imagine it a tad tricky, especially with the old blobby sac of neurons right below it), but it seemed more like a living game of operation than being a rocket scientist.

    then we have trepanning technically early brain surgery also, they have been doing that since we found we could drill a hole in our head with a piece of flint.

    we have not gotten to the whole Glue neurons back together level yet, in that respect I figure rocket scientist > brain surgeon

    that said I guess it is the whole "one-shot" deal, you can often find a bunch of brave citizens to sit atop a firework, not so easy when there is only one brain and no transplant option ( though that would be really cool brain surgery).

    >>>>>>>>>>>why paris? as unrelated as my musings...

  7. Kharkov

    Meh, not impressed...

    DARPA is a day late and a dollar short. Granted, they've got billions of dollars to make up for that but...

    They're aiming at a low-cost, reusable smallish engine which will take around... 5 years? 10? of development & testing just so they can cheaply and frequently put... 1,800kg (probably a bit less what with weight growth etc).

    Hmm, what's highly likely to be in service in 5 to 10 years time? Well, chances are there'll be a reusable Falcon 9, putting 6,000kg into LEO for... 40 million dollars a shot? Will DARPA's effort beat that on price per kg?

    And over in the UK, chances are there'll be Skylon, putting 15,000kg into LEO for 10 million dollars? Granted, this is a bit more unlikely than just developing a currently-operating Falcon 9 rocket but while people point out the amount of money REL needs, no-one's clearly demonstrated why REL won't eventually get it.

    So, lots of money spent, technology developed by DARPA and afterwards classified out the whazoo. FAIL

  8. Gene Cash Silver badge

    At least the USAF is doing something with the X-37B

    NASA tossed it directly in the waste bin without a second thought, and the USAF rescued it. Considering the success they've made of it, I hope they're testing all the niftycoolspystuff their hearts desire.

    1. MD Rackham

      Re: At least the USAF is doing something with the X-37B

      When Congress cuts your budget, you have to cut somewhere. So some projects get tossed in the waste bin.

      You can argue NASA's priorities, but research projects with no immediate application tend to always get cut before the big splashy projects (Mars Opportunity, JWST, etc.).

  9. John Smith 19 Gold badge

    Just a few misconceptions.

    It's not going to cruise at M10, it's got to reach M10

    Could be an hour+, could be a minute+, could be 5secs. It's all good (although they may think 1 hr at M10 is better I think that claim is likely to trigger the BS detector big time).

    With that spec there's lots of room for "creative engineering interpretation."

    "Cheating" is for exams IRL if it gets the job done, it gets the job done. End of.

    That said anyone talking SCRamjets is also talking stupid money.

    OTOH the USAFRL got a plane in the air with an actual meatsack at the controls on a Pulse Detonation Engine in 2006. Only something like M0.8-1.2 but it was v 0.8 tech at best and they are sure they could do much better.

    Incidentally that M10 is not even clear if it's M10 horizontal (leaving the other M13 to the 2nd stage) or vertical (a whole different ball game).

    BTW This project is being headed by Jeff Sponable, who ran the SDIO DC-X programme that built a VTOL M3 demonstrator for about $60m in the early 90's. The RFI talks about an "aircraft" but later in it says "aircraft like," which is also a whole different game.

    Trouble is until the "contractor open day" there's a lot that's up in the air (pun intended). 1000-4000lb fair enough but what's the shape? Form factor? Payload density? That will make a huge difference to what could work for this.

    I'd (more or less) agree with Trevor-Potts comment about this. Conceptually a simple nuke is fairly simple to construct. The AEC hired 3 Physics PhD candidates in the late 60's to try to design one given what was available in the open literature and could be purchased from the USG Printing Office. Their report is (AFAIK) still classified.

    I'll suggest that what needed 3 PhD;s 4 decades ago has come considerably down the food chain, although I'm not quite ready to say "Nuclear terrorism for skiddies" yet.

    No I can't do it. I do not hold a security classification with any organization. I'd suggest a key feature is how enriched the U235 has to be to get a fair chance of a bang. Historically that's meant to have been about 70%+ HEU, but AFAIK some have been done in the LEU range (4-20%). As water cooled reactors don't work without enriched Uranium (except the original CANDU design, which sidesteps the whole enrichment problem) that means probably 80-90%+ of the worlds reactors could source the core raw material for some unpleasantness, which implies 80-90% of the countries that have reactors could source a device of varying levels of sophistication.

    OTOH damm few countries have built aircraft to exceed M3. IIRC the US, USSR and (I think) France and that's it. The UK would probably be in there if was not for that rampant todger bandit Duncan Sandys, but we've all passed a lot of water since those days. :(

    OTOH 2 consider how many countries have achieved orbital launch where the LV routinely stages at M10.

    VTO is relatively easy.

  10. amanfromMars 1 Silver badge

    Misunderestimate Fabless Future IntelAIgent Fantasy and Super Attendant Fanaticism at One's Peril

    DARPA have bigger phish to fry and greater phorms of programs to launch and feed with world leading projects ........ ...... or be left behind reacting to everything flashing past them and crashing into crazy maladministered earthed systems of ill repute that do not compute or play well with the future and easily destroy everything and/or anything with timeless asset bubbles of expensive useless worth ..... for such things are easily made to happen nowadays with that which be now more widely known is possible .... and selflessly carefully shared with more than just an ancient few and/or ancients and a chosen few who imagine themselves as the Chosen Few. Hubris rules in that roost, methinks.

    After all, one wouldn't want to be unduly startling the natives and creating a great panic and global depression and world wide recession with a mad and manic settling of age old scores with a French Revolutionary zeal, would one, with a careless sharing of exciting information and newly discovered advanced intelligence.

  11. Anonymous Coward
    Anonymous Coward

    Nurse! Nurse!

    I see AmanfromMars1 seems to be off his meds again . . .

    Demerol, 1,000 cc IV, please. If that doesn't work, double the dosage. If that doesn't work, double it again.

    I'll be on the golf course for the rest of the day, leave me a voicemail in the morning.Ta.

    1. amanfromMars 1 Silver badge

      Re: Nurse! Nurse!

      Nurse! Nurse!

      I see AmanfromMars1 seems to be off his meds again . . .

      Demerol, 1,000 cc IV, please. If that doesn't work, double the dosage. If that doesn't work, double it again. …. Anonymous Coward Posted Wednesday 18th September 2013 19:12 GMT

      It is just exactly that sort of ribald comic response to an Informative Steganographic Advisory that allows ACTive Stealth with AI and IT every Facility and Utility to Succeed beyond the Wildest of Wicked Wacky Wet Dreams and Creative Imaginanations of a Renegade President, AC. Thanks for everything. IT is just so kind.

      I'll be on the golf course for the rest of the day, leave me a voicemail in the morning.Ta.

      Consider it hereby done with the message above via text to your lonesome oval office space.

      Wanna Play the Great Game for Real with Virtually Real Command and Control? Who Dares with IT Win Wins Everything in Anything and in All Ways, Always. It certainly beats knocking a small ball around an expensive course with grassy knolls and sandy bunkers and expecting it to be satisfying rather than boring snoring.

      cc @iankatz1000 ....... re Alternate Reality Games in AI Register for Mainstreaming News Knights.

      Capiche, Cheltenham/Martlesham Heath?

  12. loneranger

    old technology again

    Electrogravitics beats this stuff by light years

  13. YARR

    Keeping it simple

    1. Grasshopper - rather than expand fuel controlling it's descent, wouldn't a couple of tiny wings allow for a (computer) controlled descent as a cumbersome glider? Falling from that height it would reach such a high velocity that tiny wings ought to be enough to gradually steer it to a horizontal landing, kind of like an X-15. Or is that idea just impossible?

    2. XS-1 - this is probably stating the obvious, but if the second-stage rocket is non re-usable then it would make sense to design it so the rocket acts as the heat shield for the XS-1 on the ascent. Then immediately after separation the XS-1 can switch off it's engine and begin aero-braking. This ought to minimise the length of time it's leading edge has to withstand the intense heat.


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