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Reaction Engines To Fly Reusable Spaceplane 156

Posted by timothy
from the let's-just-start-here-on-the-ground dept.
RobGoldsmith writes "Reaction Engines have designed a 'reusable spaceplane' to provide inexpensive and reliable access to space. The Star Wars-looking 'Skylon' reusable spaceplane has already been designed and the team are well into engine testing. They have taken some time out from building spaceships to talk about their background, their goals, and their recent engine tests. This article shows new images of their STERN Engine, an experimental rocket motor which explores the flow in Expansion Deflection (ED) nozzles. They also discuss their Sabre air-breathing engine technology. View the Skylon Spaceplane concept, the STERN Engine and much more in this in-depth interview with the team."
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Reaction Engines To Fly Reusable Spaceplane

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  • Dollars per kg? (Score:2, Interesting)

    by rift321 (1358397)
    Can anyone find a cost per kg (or lb) of cargo estimate on that website? Not trying to detract from its value, just wanted it for comparative purposes.
    • Re:Dollars per kg? (Score:5, Informative)

      by denzacar (181829) on Monday January 12, 2009 @02:45AM (#26414055) Journal

      From http://www.reactionengines.co.uk/skylon_dev.html [reactionengines.co.uk] :

      The total development program will cost about $10 billion.

      Also... http://www.reactionengines.co.uk/skylon_vehicle.html [reactionengines.co.uk]

      Skylon Statistics

      Length: 82m
      Fuselage Diameter: 6.25m
      Wingspan: 25m
      Unladen Mass: 41,000kg
      Fuel Mass: 220,000kg
      Maximum Payload Mass: 12,000kg

      At the start of the take-off roll the vehicle weighs 275 tonnes, whilst maximum landing weight is 55 tonnes.
      At take-off the vehicle carries approximately 66 tonnes of liquid hydrogen and approximately 150 tonnes of liquid oxygen for the ascent.
      .
      .
      .
      Payload Capabilities

      The Sklyon payload bay is 4.6m diameter and 12.3m long. It has been designed to be compatible with expendable launcher payloads but in addition to accept standard aero transport containers which are 8 foot square in cross section and 10, 20, 30 or 40 feet long.
      It is anticipated that cargo containerisation will be an important step forward in space transport operations, enabling the "clean" payload bay to be dispensed with.

      The vehicle can deliver 12 tonnes to a 300km equatorial orbit, 10.5 tonnes to a 460km equatorial spacestation or 9.5 tonnes to a 460km x 28.5 deg spacestation when operating from an equatorial site.

      You do the per flight math.

      • Re: (Score:3, Insightful)

        by khallow (566160)
        Problem here is that they don't (like virtually everyone in the business world) throw out costs for the launches themselves. Still a development budget of $10 billion indicates to me that they're expecting operating profit to be somewhere around $1-2 billion a year. Suppose they make a profit of $10 million average per flight (that's $1000 profit per kg or so). That means 100-200 flights per year. If the profit is only a tenth that, then they have to make 1000-2000 flights a year.
        • by Rakishi (759894)

          You also need to add in maintenance, staff (someone has to manage and test this thing), facilities (you're housing and launching it where?), fuel, insurance and other such costs.

          Also there are only something like 20 commercial satellite launches a year and I think that includes geosynchronous orbit ones. Maybe you could double that if you add in government satellites but it's still not much.

          • Re: (Score:3, Interesting)

            by khallow (566160)

            Yes, lot of stuff needs to be added. At a glance, it looks like they can use a convention runway (though it might need to be reinforced, apparently a loaded vehicle generates a lot of impact on landing). Insurance isn't much of a cost for the launch provider. Insurance against third party harm is rather low since US launch providers need to demonstrate a ridiculously low risk of harm before they can launch anyway. Insurance for the payload should be pretty good for an RLV with the kind of launch frequency t

            • it looks like they can use a convention runway (though it might need to be reinforced, apparently a loaded vehicle generates a lot of impact on landing).

              Even fully loaded, this vehicle is better than 150 tons lighter than a 747. Much less at its designed landing weight (about 1/8th the takeoff weight of a 747). So I doubt the runway will need reinforcement.

              • Re: (Score:3, Informative)

                by khallow (566160)
                Problem is the narrowness of the vehicle. Up to 273 tons concentrated in a narrow band. They even mention it on the website (which is why I brought it up, wouldn't have thought about it on my own). And an abort and return to airport shortly after takeoff would result in a fully loaded landing. That has to be part of the design as well.
                • Problem is the narrowness of the vehicle. Up to 273 tons concentrated in a narrow band.

                  Width of the undercarriage might be an issue, but probably not. The entire vehicle puts a load on a narrow strip of runway only slightly higher than the load that either side of a 747's undercarriage put on a runway (273 tons versus 220 tons per side). While reinforcement might be desirable, doesn't look to be mandatory.

                  And an abort and return to airport shortly after takeoff would result in a fully loaded landing. Tha

              • by AJWM (19027)

                The 747 is a heavy beast indeed. In the early days of autoland systems (heavily used at airports that tend to be foggy, like Heathrow), the accuracy of the autoland system was so good that the 747s kept touching down on the same spot on the runway, overstressing that one spot. They fixed it by adding some slight dither to the autoland to spread the impacts out.

                The landing gear for a 747 uses more wheels than Skylon which reduces the 747 point loads (in terms of PSI).

            • by AJWM (19027)

              I think the DC-X, an unmanned prototype (for SSTO eventually) had composite tanks. There were serious problems with thermal flexing and penetration by cryogenic fluids that weakened the tanks.

              No, DC-X had metal tanks (I forget whether straight Al or Al-Li). You're thinking of the X-33 (VentureStar prototype), that not only had composite tanks but the hydrogen tank was V shaped, putting extreme stresses on the joint (and leading to the flex/leakage problems). Reinforcing that joint overwhelmed the weight

              • DC-XA had an Al-Li Oxygen tank and a composite LH2 tank. The think that fscked up X-33 was indeed the shape of the tank in combination with the composite material picked. It was heavier than using Al-Li in the first place.
        • THe hard part is that we did this already; The shuttle had the same issue.
          • Re: (Score:3, Insightful)

            by khallow (566160)

            THe hard part is that we did this already; The shuttle had the same issue.

            The Shuttle had serious issues aside from lack of demand (it would take the entire US launch market to achieve the design launch rate of 50 launches per year for the Shuttle). Particularly, the 1-2% failure rate and the monstrous overhead. These guys are hoping that they can get the operating costs down to a very cheap level, achieve a high reliability rate, *and* that the launch market will improve significantly to the point that by the time the vehicle flies, they can find enough demand for the vehicle.

        • by trenien (974611)

          It may be naïve of me, but wouldn't there be a huge difference between development cost and construction cost?

          What's keeping them from buildng more than one unit?

          • by khallow (566160)
            I completely ignored construction cost. It gets a lot more difficult once you take that into account. The point is, if you spend $10 billion on something risky, you are expecting considerable return. A constant rate of 20% per year in the not so distant future isn't unreasonable and may be low given the circumstances. Or maybe some sort of high growth effect (low or negative rate in the near future with huge growth rate years later), say if they built an large number of these for market a number of years af
      • The vehicle can deliver 12 tonnes to a 300km equatorial orbit, 10.5 tonnes to a 460km equatorial spacestation or 9.5 tonnes to a 460km x 28.5 deg spacestation when operating from an equatorial site.

        You do the per flight math.

        I'm more worried about the fact that it can only go in two directions: to the equator, to to 28.5deg.

  • by Dr. Spork (142693) on Monday January 12, 2009 @02:13AM (#26413915)
    I never thought that the Firefly form factor would ever actually fly, but look at the picture of the Skylon and tell me you don't see the resemblance!
  • by Amazing Quantum Man (458715) on Monday January 12, 2009 @02:28AM (#26413993) Homepage

    Reaction Engines is the name of the company. It's using conventional LOX/LH2 engines.

    And for those who are calling this Shuttle 2.0, it's unmanned.

    • Re: (Score:2, Informative)

      by rift321 (1358397)
      They allude to the ability to _shuttle_ persons into space later down the road using the craft, and specifically state that they aim to bring the cost of such an endeavor to the sub-$100k range.
    • From what I've read, they aren't conventional rocket engines. But if you know better, then please explain.

    • Re: (Score:2, Informative)

      by Hal_Porter (817932)

      Reaction engines do have a design for a manned hypersonic airliner

      http://en.wikipedia.org/wiki/Reaction_Engines_A2 [wikipedia.org]

      The A2 is designed to leave Brussels International Airport, fly quietly and subsonically out into the north Atlantic at Mach 0.9 before reaching Mach 5 across the North Pole and heading over the Pacific to Australia. ...

      The developers say it would be able fly from Brussels to Sydney in about 4.6 hours.

  • enough propellant? (Score:5, Interesting)

    by khallow (566160) on Monday January 12, 2009 @03:02AM (#26414143)

    It doesn't seem to have enough propellant mass for the task. To get to LEO, it needs something like 7.5 km/s or more in delta v (ignoring very substantial gravity and air resistance losses). If it were purely a rocket, that would be roughly 7.2 km/s (rocket equation is delta v = -4420 m/s*log(53 tons/273 tons), where 4420 m/s is perfect exhaust velocity in vacuum for LOX/LH2 burning rockets). Even if we assume we can get to Mach 5 for free (which is 1.5 km/s roughly), that leaves no more than 1.2 km/s margin. A regular rocket picks up 1.5-2 km/s or so in gravity and air resistance losses. While gravity losses might be somewhat lower (due to lift), air resistance is definitely going to be higher than the 100-200 m/s a rocket of similar size would have. So we have gravity and air resistance losses. We also have probably an inefficient nozzle design with a tradeoff between greater bell size (and efficiency in vacuum) and lower air drag. Something like drop tanks would help a little, but there doesn't seem to be the space for a lot of extra mass there. Another possibility is to use denser fuel in place of LH2 for the early parts of the flight, but that weakens the isp a little.

    • by evanbd (210358) on Monday January 12, 2009 @03:27AM (#26414231)

      You can get slightly better Isp than that, actually. For example, I get 4664 m/s vacuum Isp for O:F of 6:1 and 3000 psi expanded to 1 psi. I don't know what pressure they run at, but for a wide altitude range I would imagine it's high. Furthermore, I believe they plan to still be using some outside air even at Mach 5 -- and at that altitude, they've also got some delta-v in the altitude itself, not just the velocity. Small effects, but they help... Anyway, I don't know the details of their flight plan, but I do know that the engineers behind it are decidedly competent, and do have a detailed trajectory plan that includes good estimates of air drag and such. If you can find trajectory details, though, I'd love to see them...

      (Oh, to pick a few nits about your dv budget... 7.2 km/s is orbital velocity; don't forget nearly 500 m/s of Earth rotational velocity. So if you ignore air and gravity drag, it's actually slightly under 7 km/s total delta-v, though air and gravity drag will usually add more than 2 km/s to that.)

      • by khallow (566160)

        (Oh, to pick a few nits about your dv budget... 7.2 km/s is orbital velocity; don't forget nearly 500 m/s of Earth rotational velocity. So if you ignore air and gravity drag, it's actually slightly under 7 km/s total delta-v, though air and gravity drag will usually add more than 2 km/s to that.)

        7.5 km/s is orbital roughly. Still leaves up to 1.7 km/s which is pretty tight. OTOH, the payload could be a second stage, which gets you neatly around the problem.

        • (Oh, to pick a few nits about your dv budget... 7.2 km/s is orbital velocity; don't forget nearly 500 m/s of Earth rotational velocity. So if you ignore air and gravity drag, it's actually slightly under 7 km/s total delta-v, though air and gravity drag will usually add more than 2 km/s to that.)

          7.5 km/s is orbital roughly. Still leaves up to 1.7 km/s which is pretty tight. OTOH, the payload could be a second stage, which gets you neatly around the problem.

          Yeah I think a spaceplane should never go into orbit. Instead it should make suborbital hops. Non-aerodynamic payloads could be exchanged during the ballistic part of the flight.

      • Re: (Score:3, Funny)

        by MarkRose (820682)

        You can get slightly better Isp than that, actually. For example, I get 4664 m/s vacuum Isp

        DUDE!!! You must have a ton of warez!! Where can I sign up for Vacuum Isp?? My ISP suck0rs!! Im lucky if I get 3 Mb/s, but ur getting 4664!! NO FAIR!!!!1!

        • by khallow (566160)

          My ISP suck0rs!!

          Be careful what you ask for. No matter how bad your ISP is, it can't suck0rs as much as *vacuum* ISP.

          • Re: (Score:3, Funny)

            by dkf (304284)

            Be careful what you ask for. No matter how bad your ISP is, it can't suck0rs as much as *vacuum* ISP.

            Don't forget black-hole ISPs. They suck nearly as much as... hmm, what a choice...

    • by StevePole (1450559) on Monday January 12, 2009 @06:12AM (#26414893)

      A friend of mine works on the heat exchange system for the SABRE engines that will power Skylon. The SABRE engines are air breathing i.e. they use air they pick up on the way as fuel, hence they need less fuel at launch.

      From their website: "The Sabre engine is essentially a closed cycle rocket engine with an additional precooled turbo-compressor to provide a high pressure air supply to the combustion chamber. This allows operation from zero forward speed on the runway and up to Mach 5.5 in air breathing mode during ascent. As the air density falls with altitude the engine eventually switches to a pure rocket propelling Skylon to orbital velocity (around Mach 25)."

      More info here: http://www.reactionengines.co.uk/sabre.html [reactionengines.co.uk]

      The engine saves weight by using the same combustion chamber during both modes of operation and in air breathing mode it only cools the oxygen to it's vapour point (as opposed to full liquidization) which greatly simplifies the engine design.

      At least that's my understanding, IANARS.

      • Re: (Score:3, Interesting)

        by khallow (566160)

        Yes, that's pretty much what I gathered from looking at the design, especially the odd-shaped, untapered outlets for the Sabre engines and the fact no other nozzles appear anywhere on the ship.

        The engine saves weight by using the same combustion chamber during both modes of operation and in air breathing mode it only cools the oxygen to it's vapour point (as opposed to full liquidization) which greatly simplifies the engine design.

        This sounds like quite an effort. Would like to see if it works out. Recently, I was discussing a scramjet design [nasaspaceflight.com] with the internet:

        tnphysics: The key to a gas-and-go SSTO RLV IMO is airbreathing engines-somewhat like the Forerunner V business jet proposed somewhere on the forum (afterburning ultra-high-bypass turbofan to Mach 8, then LNG scramjet to Mach 15, then switch to LH2 to Mach 20), with a small rocket added for EOI. A metallic TPS should be used.

        At the time, I recommended reducing the complexity of the vehicle by eliminating the air-breathing turbofan at the start and using the rocket instead to get the vehicle up to scramjet spe

    • Re: (Score:2, Informative)

      by RocketGeek (566822)

      We also have probably an inefficient nozzle design with a tradeoff between greater bell size (and efficiency in vacuum) and lower air drag.

      That's why we are developing the ED nozzle :-)

      The ED nozzle is a very efficient nozzle design and provides altitude compensation across the thrust operation range. Part of the engine development at the moment is concerned with development of the ED nozzle for this purpose.

      • by khallow (566160)
        Hmmm, the problem I was thinking of was in pure vacuum. Does the pintle (adjustable central obstruction in the nozzle) improve performance in vacuum? Seems to me that if you wanted almost perfect ISP, you still need a high expansion bell on your nozzle.
    • by Plekto (1018050)

      It doesn't necessarily have to make it to orbit, though. If its goal is to merely drop a payload into space and then come back down, there's a small window for it to unload the object before it starts to drop back down. The question is whether we're talking about an hour or so or minutes.

      I suspect that they plan to have the payload have its own small engine to do the final positioning and get up to orbital speeds. 5% change it actually works. It looks fancy, but seems to me to be yet another company th

      • by khallow (566160)

        Quite true about the RLV. It should also be good for suborbital flights.

        Loads of good intentions but little likelihood that it will actually work. (see SpaceX for a perfect example)

        SpaceX is perfect example of what? 1) They don't troll for rich investors, 2) they actually work (I know, 1 out of 4 sucks, but it's a lot better than 0 out of 0), 3) they're getting some serious contracts.

  • Sky-Lon? (Score:5, Funny)

    by pcgabe (712924) on Monday January 12, 2009 @03:28AM (#26414237) Homepage Journal

    Sounds like a Skynet-Cylon joint venture. Please don't be sinister-looking....

    *Opens link*

    Ah, crap.

  • does this add up ? (Score:4, Interesting)

    by freddy_dreddy (1321567) on Monday January 12, 2009 @03:40AM (#26414287)
    from this presentation [space.co.uk]:
    - air intake in the order of hundreds of kg per second (400 kg/s to quote) ...
    - passes through thousands of small tubes (resistance at that speed ?!?) ...
    - in a few milliseconds ...
    - cooled from + 1000degreesC to -150degreesC

    Forgive me my ignorance, but are these materials physically possible ?
  • by VincenzoRomano (881055) on Monday January 12, 2009 @03:47AM (#26414321) Homepage Journal
    Hmmm ... I would suggest GL to sue that company for (R) infringement!
    And later (from a galaxy far far away) the Empire will sue GL!
  • Reaction Engines Ltd have been working on this for well over 10 years now (maybe closer to 20) with not a lot of actual hardware to show for it. I first heard about Skylon when I was still in uni, around 1996 or so, and not much has happened since. So while the Skylon design is inordinately cool, with some very nifty and innovative features, I'm afraid it's never going to actually fly.

    Sad, really, as it's one of Europe's few contenders in the non-gov space race, and probably the most promising one, in ter
    • by Stoutlimb (143245)

      It might fly, but will it stand the heat of re-entry? There doesn't seem to be any heat shielding at all. I'm wondering how it's not going to disintegrate?

  • I checked out their video gallery. These people know what they're talking about.

    -jcr

  • a 21st Century DC-3 (Score:3, Interesting)

    by alizard (107678) <alizardNO@SPAMecis.com> on Monday January 12, 2009 @05:15AM (#26414665) Homepage
    From what I saw at the company website, it looks like they're building the orbital equivalent of the first commercial airliner, the DC-3.

    If they can get the cost to orbit even remotely close to the $200/kg number the Space Power Satellite program proposed by NASA was based on, we could either build a full system or a large proof of concept orbital power array. We're a bit more desperate for power than we were when Bush defunded the SPS project. The launch capability is the hard part of SPS, the rest is just engineering we know how to do.

    That could take up enough launches to provide the company a reasonable chance at profit.
    • Re: (Score:3, Funny)

      From what I saw at the company website, it looks like they're building the orbital equivalent of the first commercial airliner, the DC-3.

      Cool. Now if we can just scale up to build space DC-8s, we can take all the scientologists to another planet and drop them in a volcano.

    • Re: (Score:2, Interesting)

      by rarel (697734)

      From what I saw at the company website, it looks like they're building the orbital equivalent of the first commercial airliner, the DC-3.

      Bit of a nitpick here, but that would be the first tremendously successful commercial airliner.

      The DC-3 was an evolution of the DC-2, which was designed to compete with Boeing's 247. The 247 itself was preceded by a bunch earlier designs by various constructors, like the Ford Tri-Motor.

  • HOTOL? (Score:2, Informative)

    by footnmouth (665025)
    Hmm... as I'm getting old I thought I remember this concept as HOTOL, and sure enough: wikipedia [wikipedia.org] Reaction engines was started by one of the HOTOL designers. Still, it's had probably 30 years of intellectual development and it looks believable to me. Go Reaction Engines.
  • Whilst (Score:3, Informative)

    by necro81 (917438) on Monday January 12, 2009 @10:28AM (#26416429) Journal

    Skylon will be able to repay its development costs, meet its servicing and operating costs and make profits for its operators whilst being an order of magnitude cheaper to customers than current space transportation systems.

    Can I trust my payload and/or investment dollars to a company that uses "whilst" on their site? [reactionengines.co.uk]

  • There's another kind? Tell me more!

COMPASS [for the CDC-6000 series] is the sort of assembler one expects from a corporation whose president codes in octal. -- J.N. Gray

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