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Science

Scramjet Success in Australia 238

Posted by chrisd from the faster-than-a-speeding-uh-sr71 dept.
glengyron writes "Australia's ABC reports today that a University of Queensland team have successfully tested a supersonic scramjet (air-breathing supersonic combustion ramjet engine). Read more here or here. Great to see after previous problems. Does the future of air travel still include those breakfast egg-roll things?"
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Scramjet Success in Australia More

Scramjet Success in Australia

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  • "Until this morning no organisation, including NASA in the United States, has been able to successfully test fly a scramjet - an air-breathing supersonic engine. "

    I'm not too sure about this... donuts on a rope anybody?
    • I doubt it.

      The donuts on a rope phenomenon has, to the best of my knowledge, not been fully explainet yet (i.e., nobody is fessing up as to what plane is making those contrails).

      The most plausible explanations I can see for it require some sort of pulsejet engine. I'd expect scramjet engines to generate contrails similar to ramjet engines, since the shift to supersonic speeds doesn't turn any other supersonic engine's contrails into donuts on a rope.
      • "Donuts on a rope" HAS been explained. It is produced by PDW (Pulse Detonation Wave) engines. What hasn't been explained is what is making them, as there are no PDW engines officially in use yet. Much speculation is that the ultra-secret US spy plane Aurora is what's creating these. Some spy plane, if it leaves such a distinctive signature!
        • Spy planes don't necessarily have to be stealthy - the SR-71 and U2 survived not by stealth (the Russians could easily detect them on radar) but by flying too high for Soviet interceptor aircraft and SAMs to reach them (and in the case of the SR-71, it also flew faster than anything they could throw at it).
        • "Donuts on a rope" HAS been explained. It is produced by PDW (Pulse Detonation Wave) engines. What hasn't been explained is what is making them, as there are no PDW engines officially in use yet. Much speculation is that the ultra- secret US spy plane Aurora is what's creating these. Some spy plane, if it leaves such a distinctive signature!
          Makes sense. An explosion (a high-pressure squirt of gas) funnelled through a narrow exhaust pipe will most likely produce a torus, like a smoker blowing rings of smoke, or a diver making ring-bubbles at his decompression stop...
      • There's speculation that the donuts-on-a-rope photos that were in Aviation Leak a few years back were created by a Pulse Detonation Wave [tripod.com] engine. The donuts imply distinct combustion pulses (like in an internal combustion engine, only much slower), as opposed to continuous combustion (turbine).

        Another theory is that the donuts are some sort of weapon; the "rope" is the contrail left by the aircraft's engines, and the donuts are exhaust pulses from a gun or something.

        What it comes down to is that like you said, nobody knows what created the phenomenon.

    • Ohh, of course, NASA should have really been first to pull this off, considering "U S A" is number 1 and all. Now we have this technology, you won't even see the planes coming till it's too late. Ha Ha Ha Ha Ha Ha Ha Ha.
      • ...LCA2003 [linux.conf.au], and now working scramjet engines! Australia seems to invent the best of everything. (-:
    • "Donuts on a rope" are caused by shock waves in the stream of a jet engine; they'll show up in nearly any high-output jet engine, much less one meant for supersonic travel.

      If you're thinking of the neat light display behind the engines of a SR-71 Blackhawk, those engines are indeed for supersonic flight -- but they aren't ramjets. They're turbofans. They are configurable, though; the cone on front adjusts the position of a shockwave that slows the air down to the point where it will work in that type of engine.

      The difference is that a scramjet, having no turbine and only basic moving parts, can operate at a much higher velocity than a turbojet. The SR-71 was limited to the supersonic realm, while a scramjet-powered vehicle can reach hypersonic speeds, above Mach 10.
      • "Donuts on a rope" is the characterisation given to the contrail of a secret US program thought to use pulsed detonation to achieve high mach.

        "shock waves in the stream of a jet engine" are better known as shock diamonds and are the results of shock waves producing visible artifacts in the flaming exhaust of aircraft using afterburners.

        Finally, as has already been stated in another post, the SR-71's engines fonction in both ramjet & turbojet modes. The inlet cone slows the air down to subsonic speeds so that it can be used in the ramjet part of the engine profile -- using hypersonic air is the definition of scramjet.
  • Rome invented scramjets.

  • A little more info (Score:5, Informative)

    by Bastian ( 66383 ) on Tuesday July 30, 2002 @03:35AM (#3976632)
    A diagram of the difference in design between a ramjet and a scramjet engine can be found here. [aviation-history.com]

    For more information, check out the HyShot homepage. [uq.edu.au]

    • Re:A little more info (Score:5, Interesting)

      by ender81b ( 520454 ) <wdinger@@@gmail...com> on Tuesday July 30, 2002 @04:06AM (#3976709) Homepage Journal
      A little more info from Encylopedia Astronautica [astronautix.com]. A scramjet is vastly more efficent than standard chemical rockets because only half the fuel has to be carried (hydrogen). Also scramjets have a greater ISP than most regular chemical engines and have no moving parts, unlike the hundreds of parts on moden rocket engines.

      Taken from here [astronautix.com]

      air/LH2 (scramjet) ISP=1,550

      Space Shuttle Main Engines [astronautix.com]

      ISP = 453

      Obviously scramjets are vastly more efficent. Of course ION engines have ISP values of roughly 5,000-6,000 and fusion another magnitude greater, etc. Still lots of room for improvement.
      • Obviously scramjets are vastly more efficent.
        In an atmosphere, yes. Once you get outside the atmosphere, they're useless.

      • Of course ION engines have ISP values of roughly 5,000-6,000 and fusion another magnitude greater, etc. Still lots of room for improvement.

        Yeah, except ion engines don't work at all in an atmosphere, and scramjets only work in an atmosphere; they're two totally different systems for totally different purposes. Also, ion engines need an external power source, which increases vehicle mass, while scramjets are self-powered.

        Fusion engines could potentially replace all propulsion we use now, sure, but we don't have fusion engines, and it's uncertain whether we'll ever be able to build a small enough fusion engine to fit on any spaceship smaller than a few thousand kilograms. And even then, you still need some reaction mass, just like in a nuclear thermal rocket. What should you use as reaction mass? Well, if you're in the atmosphere, you could use air. Kind of like a scramjet.

        Of course, we could build a fusion pulse rocket right now. Just get a huge bowl, with shock absorbers and a spaceship above it, and explode a few hydrogen bombs underneath.

        • Interesting points. Tho' scramjets aren't totally self powered; they do need fuel ;)
        • Of course, we could build a fusion pulse rocket right now. Just get a huge bowl, with shock absorbers and a spaceship above it, and explode a few hydrogen bombs underneath.

          Actually, this is an old concept known as Daedalus [geocities.com] and was invented by the British Interplanetary Society.

          Yours Yazeran

          Plan: To go to mars one day with a hammer.

          • Of course, we could build a fusion pulse rocket right now. Just get a huge bowl, with shock absorbers and a spaceship above it, and explode a few hydrogen bombs underneath.

            Actually, this is an old concept known as Daedalus and was invented by the British Interplanetary Society...

            Readers of Niven/Pournelle's Footfall will recognize this as Orion [iinet.net.au], which was used as part (first stage?) of the Daedalus project's craft.

            --Jim
      • Also scramjets have a greater ISP than most regular chemical engines and have no moving parts, unlike the hundreds of parts on moden rocket engines.

        In its simplest form rocket engine has no moving parts either (ok, there's usually a few valves, but scramjet would need them also.)

        The Space Shuttle Main Engines have complicated turbopumps, but I wouldn't exactly hold that up as a shining example of rocket engineering; but the SRBs don't have any moving parts.

        ISP is not everything- it's recently been realised that fuels that have lower ISP can give more payload to orbit than hydrogen/LOX. Reaching orbit is much more subtle than you would expect. Scramjets actually look like a bad idea for reaching orbit; they're too heavy- but may be good for a first stage, where the weight doesn't matter nearly so much.

    • Re:A little more info (Score:5, Insightful)

      by tony_gardner ( 533494 ) on Tuesday July 30, 2002 @04:07AM (#3976712) Homepage
      Unfortunately, the diagram is not totally correct. It's possible to have scramjets with duct convergences, and ramjets without duct convergences. The difference lies in the fact that in a ramjet the air becomes subsonic, and in a scramjet the air does not become subsonic.
      Making the air subsonic provides a great deal of control over the combustion process, thus the problem with scramjets.
  • How come the site says this then?
    "Dr Paull said although the signs so far have been positive, it is still too early to say the scramjet experiment has succeeded. The scramjet experiment took place within only the last few seconds of the flight, lasting almost 10 minutes."

    (OK - I'm hair splitting, it looks positive, but jumping the gun like this doesn't help anyone if it turns out that everything was just a fluke ;-)
    • "Successfully tested" should be read as: "At leased it has not exploded"
    • But hey! Who wants to read THIS story?:

      "Scramjet tests looked positive in Australia"

      Hey! Wait a minute! That IS the story we're reading. Call a shit Lola and its still a shit!
    • Mainly because last time, the rocket veered off course and crashed into the ground before the test could be conducted. This time, the rocked stayed on path, they received telemetry from the package, and nothing spectacular went wrong. It is still very possible for something non-spectacular to go wrong, and clearly they're avoiding talking before thinking (an increasingly rare occurrence).
    • It was a successful test, in that the engine ignited properly, and they collected bucketloads of data from it.

      However, Dr Paull is being cautious (and rightly so) because the program itself is not yet a success. They have to make sure it's repeatable, and then start the task of transforming it from a nice /. article into something that can be used practically.

      Good luck to them, the more space research we have in Queensland, the better.
  • Little bit less of a press release, little bit more information including a better explanation of the flight profile at

    http://www.mech.uq.edu.au/hyper/hyshot/
  • OK first off, the abc.au news piece was an abomination of English:
    "In South Australia's outback history has been made with a team from the University of Queensland successfully flight testing their supersonic air-breathing scramjet engine atop a rocket.

    How about:
    A University of Queensland team made history today when they launched their super-sonic airbreathing scramjet engine atop a rocket. The test was conducted in the outback and was the first successful one of it's kind.

    Yech, even that one sucks, easier to read though.

    Anyhow, on to the point. Later in the article, it said data was recorded from the descent. Is that descent back to earth or what? Was it controlled or did it just crash land? The other page has almost as little information too, unfortunately.

    • Later in the article, it said data was recorded from the descent. Is that descent back to earth or what? Was it controlled or did it just crash land?

      The descending flight plan was intentional; the speed needed to ignite the motor is quite high, and a gravity assist helped to attain it. The scramjet fired during the last portion of a parabolic flight.

      Plus, I bet they didn't want to risk the vehicle flying off in an unintended direction if it worked too well; with the chosen flight path it was stopped directly after the experiment concluded :-)
    • Yes it was controlled, and yes it did crash land (Why should the two be exclusive?) The rocket has a ballistic trajectory, and the experiment is performed on the way back into the atmosphere (between 32km and 22km altitude), for about 4 seconds, you can work out the speed yourself. It then has about 10 seconds before it hits earth. When the payload of the last attempt was found, the nosecone was buried about 1 meter below ground, and it only flew upward for about 10 seconds. The current experiment goes upward for 5 minutes.

      Suffice to say, that this is an unmanned experiment.
    • of it's kind

      Apostrophe not needed for this possesive....

      As for Is that descent back to earth, where else if not descent to the earth? You think this was done on Mars or somewhere?

  • Woomera is the place to be in Australia... (Score:3, Funny)

    by v8interceptor ( 586130 ) on Tuesday July 30, 2002 @03:42AM (#3976646)
    Successful scramjet tests, crazy Japanese rocket flops - I don't know what the refugees are complaining about, look at all the entertainment they get!

  • Didn't the russians already test ScramJets (brought up to speed by rockets, just like this one) a couple of years back? IIRC it was even successful. Definitely not a first here in Australia, then...

    • Re:Russians? (Score:3, Informative)

      by tony_gardner ( 533494 )
      There was a joint flight experiment between NASA and CIAM (Central Institute of Aviation Motors, Moscow), in 1998. There were three tests. they were launched on modified Russian SA5 missiles. One failed outright. One tested the engine in subsonic mode, and the third did not achieve supersonic combustion in the engine.

      I think that the outcome from these experiments could be summarised as that no working scramjet was flown. As a note though, the main objective was to prove the Hypersonic flying laboratory, "Kholod", which is a package with fuel and telemetry to attach to a rocket so that any experiment can be easily flown on a rocket. This package was successfully tested (ie fuel, power and telemetry were provided to the model)

  • Australia's inventing all the cool stuff. (Score:5, Interesting)

    by marcsiry ( 38594 ) on Tuesday July 30, 2002 @03:47AM (#3976655) Homepage

    First the Metal Storm [wired.com], now this!

    Soon Australians will be able to fly up to anyone, anywhere in the world, within minutes, and then cut them to ribbons.

    I wish I was Australian.
    • If you have broadband, visit the videos page [metalstorm.com]. It is awesome. The aussie voice makes it seem even cooler when rapid fire bullets rip through multi-layers of wood. This is quite a cool product. I can't wait to have one in my glovebox :)

      Chris

    • This [kel.com.au] could do air traffic control in the USA if we wanted it to. (-:

      This [kanwa.com] can't see quite as far, but does pick out nearby* stealth aircraft in stark relief without any apparent effort (`bombers flying at low altitude' includes B1s and B2s). And there are about 70 Chinese in China for every Australian in Australia...

      * on the first bounce, ie, out to just shy of 1000km away.

    • I wish I was Australian.
      If you want to be an honorary Australian, follow these simple rules:
      • Say crikey at least 5 times a day.
        Good Australians say it early and often.
      • Pretend your dog is a 'roo. And for crikey's sake, man, watch out for
        those hind legs! They can gore a man!
      • Refer to Americans as yanks.
      • Above all, make fun of the English.

      If you follow these rules, you too can attain that Australian aura.

    • Hrm. Assume the average bullet weighs 10 grams. 1,000,000 bullets/minute * 10 g/bullet = 10,000,000 grams of lead per minute; that's 10,000 Kg... Given 2.2 lbs/ Kg, that's 4,500 lbs of lead, or about as much weight as a minivan.

      So my question is... what good is this thing, if the battle lasts more than 10 seconds?
      You'd have to have an ammo depot the size of a house sitting right next to the thing.
  • First link doesn't work for me... this [abc.net.au] appears to be correct.

  • Any more detailed images of the HyShot? (Score:3, Funny)

    by RyanFenton ( 230700 ) on Tuesday July 30, 2002 @03:50AM (#3976668)

    No goatse links, thanks.

    I'd be interested in seeing what this implimentation of a scramjet looks like on the actual craft.

    I've done the usual google search and found this [uq.edu.au] (which was very nice, but is a little video, not a good image), and this [uq.edu.au],but was wondering if anyone has found anything more detailed. :^)

    Ryan Fenton
  • chrisd, do you actually READ articles before posting?! It's the second one with broken links out of two posted by you today :)
    HINT: try to sleep more...
  • Let's see: First news link was DOA. Second one says "University of Queensland researchers say they are receiving data from the rocket, but it is too early to say whether the experiment has been a success." which /. interprets as "Successfully tested."

    Salshdot editors must feel pretty giddy with their manifest-destiny powers, if writing a headline can make something so...
    • I've thought about this a bit recently.

      Wouldn't it be quite easy to code up something that went through all the links in the submissions bin and reject them (or at least edit the message to reflect it, so the editor can try to find the right one). That way it would be solved automatically

  • ...the Getthehellouttaherejet, but "Scram" was so much simpler and to the point...
  • I just cant stop thinking about Vermicious Knids.

    This needs to be modded to "+5 What the Fuck?"

  • "Successfully tested" (Score:4, Funny)

    by Hitokage_Nishino ( 182038 ) on Tuesday July 30, 2002 @04:00AM (#3976698)
    Well, considering the feat of testing was accomplished instead of the plane exploding and crashing on unaware kangaroos... one could say they had "successfully tested".

  • DARPA appear to have done it already (Score:3, Informative)

    by sambo99 ( 224628 ) on Tuesday July 30, 2002 @04:01AM (#3976699) Homepage
    Looks like will have faster bombs, way before we have faster airliners ...

    http://216.239.39.100/search?q=cache:MKgyf6-JQS0 C: www.darpa.mil/body/NewsItems/pdf/hyfly.pdf+scramje t++Defense+Advanced+Research+Projects+&hl=en&ie=UT F-8
    • http://216.239.39.100/search?q=cache:MKgyf6-JQS0C: www.darpa.mil/body/NewsItems/pdf/hyfly.pdf

    • Hrm. For some reason, copy-paste puts a few unwanted spaces in the link. Oh, well--here's a link [216.239.51.100], maybe that'll work.

      Anyway, I think 11 September really kinda blurred the line between airliners and bombs. A faster airliner is a bomb in the wrong hands.

  • The page or file you've requested, "http://www.abc.net.au/news/justin/nat/newsnat-30j ul2002-53.htm" doesn't seem to exist on this server.

    hmmm you'd think after so many people on slashdot complaining to slashdot editors to check links before they post articles... they would!!... then again... these are slashdot editors...

    • Therre is a better article anyway at the BBC [bbc.co.uk]
    • hmmm you'd think after so many people on slashdot complaining to slashdot editors to check links before they post articles... they would!!... then again... these are slashdot editors...

      It was there when I read it. Of course, I read it before there were any posts on the board.

      You have to remember, ABC is our government funded free to air TV and news channel. They are running on a rather tight budget....

      They wouldn't be able to take much of a Slashdotting.
  • From the University of Queensland site:

    "University of Queensland researchers say they are receiving data from the rocket, but it is too early to say whether the experiment has been a success."

    It seems the "Scramjet Success In Australia" title might be a little premature, as it is at least slightly misguiding.

  • At least this time those clever scientist types remembered to bolt the test vehicle to the rocket engine.

    Anyone remember the poor Japanese SSTV model a few weeks ago?

    But seriously (did I just say that?), one of the problems with SCRAMJETs is their gobsmackingly high fuel consumption.

    This is one of the reasons that scientists are also exploring pulse detonation engines [aardvark.co.nz] as an alternative super/hypersonic propulsion engine.

    It is rumored that the PDE-powered craft are responsible for those "donut on a rope" contrails seen by some high above the USA.
    • Depends that you mean by high fuel consumption. They go fast, and this creates drag, thus fuel must be expended. It you mean low efficiency, then you are half right: No scramjet achieves good fuel efficiency at the moment. However, since there are not really any working scramjets that should come as no particular surprise.
      Generally, Scramjets should work in the range Mach 6 to 20. I've never seen an upper limit on pulse detonation engine operation, but I can't remember ever seeing one that worked over Mach 8, even in theory.
  • I know less than nothing about this technology, nor what it would be used for, therefore I must post to this topic ;) Mod me -1 dumb if you must, but here are my questions:

    1) What is this engine useful for?

    2) What industries would this apply to?

    3a) Is there video anywhere of the launch/flight?

    3b) How bout the crash landing, I'm more interested in that. Any video on that?

    Thanks.
    • Firstly, it is not really useful for passenger aircraft. The high G to get up to speed is not really sellable.

      The main use is as a secondary engine for rocket propulsion. Since atmospheric air is used, the scramjet theoretically can lift more payload for a given engine weight, and it is hoped that this will translate into launch cost savings for light payloads (I've seen one estimate that put the saving at a factor of 10 for a 1-10 tonne payload), however nothing really beats rockets for very large payloads.

      The biggest advantage, in a launch to orbit is that, since the engine will be going sideways to pick up speed, the cost difference between a polar and equatorial orbit is negligible.
  • Here's a URL for the ABC that should work.

    http://abc.net.au/news/australia/qld/metqld-30jul2 002-15.htm [abc.net.au]

    It doesn't really say much that the UQ page hasn't already but at least it confirms where those /. editors got their headline.

  • Corrected ABC.NET.AU link (Score:3, Informative)

    by caveman ( 7893 ) on Tuesday July 30, 2002 @04:37AM (#3976766)
    Another route to what would seem to be the right page is here: http://www.abc.net.au/news/2002/07/item20020730140 728_1.htm [abc.net.au]
  • http://www.abc.net.au/news/australia/sa/metsa-30ju l2002-9.htm
  • Not according to this press release [af.mil] from the Arnold Engineering Development Center [af.mil] at Arnolds Air Force Base, Tennasee.
    They claim to have flown, albeit briefly, a scramjet vehicle in August of 2001. Acceleration to operating speeds was achieved using a very big gun!
  • A brand new series of Roger Scramjet !

  • *THUD* (Score:3, Funny)

    by TheSHAD0W ( 258774 ) on Tuesday July 30, 2002 @06:14AM (#3976974) Homepage
    Until this morning no organisation, including NASA in the United States, has been able to successfully test fly a scramjet - an air-breathing supersonic engine.

    Umm, I'm sorry, but in my humble opinion, heading straight down and digging a crater in the ground does not constitute "flying". Please be more accurate in your description.
    • It does if the vehicle maintains velocity under its own power.
      At Mach 6.7 if there is no active thrust to maintain that velocity then deceleration will happen pretty quickly. What the flight team are looking for is data to show that the vehicle did indeed maintain velocity, indicating that thrust had been generated by the engine.
  • So does that mean we can all look forward to
    Scott Scramjet and his Australian Eagles!

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