A Million Bucks, Mach 7.6, Straight Down 186
Dspiral writes "At the Canadian publication, The Globe and Mail, they
write about the scramjet.
A jet engine, with theoretical speeds over 8000 Kph, and pollution free!" Zero pollution because its fuel is hydrogen
(a scramjet
takes its oxygen from the air).
The HyShot homepage
is amazing; the beast has been built on a shoestring, barely over a million dollars Australian, and my favorite part is their planned test:
"...shooting an engine into the atmosphere on a rocket, and hoping it will ignite as it plunges back down to Earth. Mr. Paull's speed objective is Mach 7.6, and the engine should ignite 23-35 kilometres off the ground."
Actually, it's a scramBRAKE (Score:1)
Re:Umm. hello? (Score:1)
It was the major British missile-testing range in the 1950's and '60's, so it's no stranger to high-Mach crashes (especially the disastrous ELDO European launcher program; oh well, at least the Ariane project found out from it what *not* to do!!!). Similar flights to this experiment were done during the Black Knight project, where a rocket was fired out of the atmosphere, then back down, with the added twist that a second stage rocket was fired on the way *down* to accelerate it! The purpose was to test ICBM/IRBM re-entry cones, so I imagine they came down a *lot* faster than Mach 7.6.
I believe it was some of the most important work done at Woomera, and assisted the development of ablative coatings in the US Mercury manned capsules as well as re-entry cones on the first generation of US ICBMs.
My great dream as a kid was to work there, but its glory days were over by 1980. Now it's used as holding area for illegal immigrants... Ironic, innit; when I was a kid Woomera was a symbol of how far Australia had come since being founded as a prison. Now it's a prison itself :-(
Re:Canadians and Australians... (Score:1)
The NASA project I think will be being launched from a B52 aboard a Pegasus rocket, so it still needs a boost.
Of course, there's also the question of whether a scramjet is a good idea at all. It needs hydrogen, which is one of the least dense rocket fuels out there, which makes the structure larger for a given payload (which is bad); also, since a scramjet needs to hang around lower in the atmosphere than a rocket, it's subject to much higher aerodynamic forces and heat loads. Finally, the engines thus far designed have weighed more than the oxygen they're replacing. When you consider how cheap liquid oxygen is, a lot of people wonder, why bother?
This is cool (Score:1)
All your scramjet are belong to us! (Score:1)
Of course I bet if it costs $1M Aus to make, it will cost the US Military about $50M US to make.
Re:They launch jets that way (Score:1)
oooo free cheers for Mr. No it All and my ass is so tight I cant' see I joke if it got up and bit me
yea but who is gonan ride the thing ? (Score:1)
yea I really like my brains in the back of my head. reminds me of the Ren and Stimpy episode " must saaaaavve braain"
now I remember (Score:1)
didn't they used to attatch these things to helicopter rotors. The Rotors were powered by a minimalist engine then as they began to turn the air forced through the system would be mixed with some fuel and come shooting out the other side. very simple design my question is it only works most efficiently at lower altitudes as opposed to space since they require O2 from the atmosphere. Not only that they require an initial velocity to get them going. I can see it now tomohawk missles being launched off the USS Nimitz with large elastic bands.
Re:Hydrogen fuel? (Score:1)
Two thirds of the Hindenburg passengers lived, which is a better record than a lot of airliner crashes.
Real (not paper) scramjets are new (Score:1)
Ramjets that slow the air to subsonic speeds before combustion are old hat, of course.
Re:The Aurora Project (Score:1)
Re:wow, we'll here about this again very soon. (Score:1)
"Man and car missing in Illinois"
"Illinois license plate found in Australia"
(20 years later)
"1990 Volvo Stationwagon found in the Mariana Trench"
Re:This is old, and written by an idiot. (Score:1)
The page actually reads under lynx
(and any pointers to getting X 6.4.1 to run on a
Toshiba Satellite Pro 420CDT?)
Lord Bhaal
Re:Remember Enterprise? (Score:1)
Re:Some thoughts... (Score:1)
High speed air breathing flight is STUPENDOUSLY difficult. It's only been in the last five to eight years that the computers are fast enough to even BEGIN to model the supersonic flows through a scramjet, and the problem is very far from being solved. Rockets are ugly and pedestrian, but they do the job better than any technology on the drawing boards.
You are correct Johnny (Score:1)
Didn't you ever wonder why the SR-71 has all those corrugations? That is the design, when it is hot the joints seal.
Pretty cool if you ask me, and this from 1960 tech.
Too bad the XB-70 never made it into production, it was cooler on all points, and a much cleaner aerodynamic design.
Re:Canadians and Australians... (Score:1)
Re:Wondering.... (Score:1)
Re:scramjets (Score:1)
A Hawk Among Sparrows?
That story has haunted me since I read it.
Re:hope they don't pull a NASA.... (Score:1)
Re:GPS-enabled Auto-Suicide (Score:1)
You mean like this [venco.com.pl]? Note this comes from the album 'Red sails in the sunset' by that very fine aussie band Midnight Oil. One of their better albums by the way.
g-force (Score:1)
_______________________________________
Re:How will it stop? (Score:1)
They're going to throw a planet at it. That'll stop it real good.
Hydrogen pollution (Score:1)
Re:Canadians and Australians... (Score:1)
Yeah, when NASA sends something straight down at Mach 7.6, it costs way more than a million bucks. And sometimes it doesn't even achieve Mach 7.6 on impact.
Anyone want a couple of slightly-used Mars probes?
Re:Some thoughts... (Score:1)
Later
Erik Z
Re:Wondering.... (Score:1)
Re:The meaning of SCRAMJET (Score:1)
Re:You are correct Johnny (Score:1)
Re:So... uh... how deep? (Score:1)
--
No Pollution ? (Score:1)
Unfortunately, water has one of the highest specific heats of atmospheric gases. Some information I have seen (I forget exactly where) labels water vapour as a much worse green-house gas than carbon dioxide.
All in all, I would rather have our atmosphere contaminated with water than with CO2. In high concentrations, we just get hotter, more humid days. With CO2, breathing becomes labourious.
Re:Some thoughts... (Score:1)
True, but O2 weighs ~ 24 times that of H. I would think the weight cutting benefits would be just as enormous... someday... :-)
Finally! (Score:1)
Oh.
Wait.
Check out my diary [diaryland.com].
Re:Late 2000? (Score:1)
and at the bottom of the page,
"Modified:19 June 2000"
did they all just forget or something.
Maybe the new Australian cencorship laws kicked in, and they werent allowed to publish anymore info.
Rocket=Phalack symbol????
make sure all loose objects are properly fastened. (Score:1)
Think, air rage would be a thing of the past if everyones lips are flapping behind their heads and they're unable to move due to the sheer force of takeoff.
Re:Some thoughts... (Score:1)
Re:FP? (Score:1)
Nipok Nek
Only 11.5k/s (Score:1)
Re:Wondering.... (Score:1)
This is a university project.
One problem remains. (Score:1)
So you need to speed up the damn thing for it to work properly. Booster rockets work well for this, so they'd have to use those.
Btw, the V2 rockets used by Germany in WWIV used ramjets, if I'm not mistaken. I guess they just made them a bit faster now.
bart
How (sc)ramjets work. (Score:1)
This happens at a pretty high frequency, depending on the how efficient the combustion is.
So you need air to make this thing work. You need fuel, which you carry already. If you wanted to travel in space, you'd need to carry oxygen, too, and keep one end permanently closed. So you end up with a rocket.
Oh well. No space travel with these babies.
er...hydrogen? (Score:1)
Re:The 'hydrogen is polution free' lie (Score:1)
----------------------------------
Re:One problem with scramjets... (Score:1)
I'd imagine that a couple miles of magnetic linear accelerator might do the trick to get them up to >= mach 2. Wouldn't be practical unless you planned on launching a lot of them though.
Re:Canadians and Australians... (Score:1)
There's no reason why a (sc)ram jet has to be powered by hydrogen, you could probably power one with kerosene if you wanted. As a matter of fact there was a USAF project a few decades ago to develop a fission powered scram jet ( Project Pluto [voughtaircraft.com]) for deliverng nuclear warheads. Needless to say it wasn't nearly as environmentally friendly as hydrogen power.
Also, I've seen ram jets built by hobbyists that about the size of a soda can - scram jets don't neccesarily have to be any bigger.
I think scram jets can be developed into a very viable means of providing very fast, cheap, sub-orbital propulsion.
Re:One problem with scramjets... (Score:2)
The SR-71 incorporates what's called a mixed-compression inlet, that is the _external_ big (movable) cones do some of the compression, setting up a conical shock wave, and then an _internal_ "shock train" (several small "linked" shock waves) inside the inlet lip do the rest of the slowing down and inlet flow compression to subsonic. Now at full speed, the SR-71 is operating with the J-58s in full afterburner. The "ramjet" designation comes from two details.
One is that at full speed, a good portion of the air that passes through the inlet then gets ducted directly to the exhaust nozzle -- but this air has already contributed to the thrust because it is part of the high-pressure stream pushing on the back of the inlet cone (higher-pressure against aft-facing area is thrust, boys and girls).
The other detail is that the J-58 engines have big tubes that at high Mach, bypass a lot of flow past the high-pressure compressor stages and directly to the afterburner. This bypassed air doesn't see a turbine, so it's "like" a ramjet in that sense. But because the majority of the flow at least passes through the gas turbine engine's compressor and afterburner, it's not a "true" ramjet.
Re:One problem with scramjets... (Score:2)
While an engine that could do ram/scram certainly would have a larger operational flight Mach number range, it wouldn't be able to get off the ground on its own (i.e. no static or subsonic thrust). Research has indeed been done on combined gas-turbine ("conventional jet")/(sc)ramjets (known as "combined-cycle" engines), and that kind of beast could potentially have the the full envelope capability. Also, don't confuse the SR-71's so-called "turboramjet" as being a combined-cycle engine. It doesn't have a true ramjet-type flowpath, and the compressor would start to melt if the flight speed reached "true" high-speed ram/scram speeds.
All this kind of talk, though, is sort of pie-in-the-sky and ignores the fact we've still not yet demonstrated a free-flight scramjet-powered vehicle. That's what NASA's Hyper-X project is supposed to address. You can get more info on Hyper-X via http://www.dfrc.nasa.gov/ [nasa.gov]
BTW, as you might have guessed, IAAE (I am an Aerospace Engineer)...
Scram jet huh.... (Score:2)
--
Re:Some thoughts... (Score:2)
This is why NASA is working on a launch system that runs on an inclined rail using electromagnets. (from a past
Re:One problem with scramjets... (Score:2)
Re:Some thoughts... (Score:2)
I Am Not A Clueless Newbie.
Some thoughts... (Score:2)
It follows that ultra-light rockets that can achieve orbit would be practical, using this kind of technology.
Second, it -ALSO- follows that giant rockets, capable of putting entire large-scale constructions into orbit, would be practical, as it would be within the sorts of costs you expect for modern rockets.
By implication, if the Oz engine works, you could start seeing groups of High Schools (with a bit of sponsorship) lobbing entire space-stations into orbit, rendering the ISS completely worthless.
(Which, to be honest, is an accurate assessment anyway.)
Re:The 'hydrogen is polution free' lie (Score:2)
Unfortunately, this method produces gas-state hydrogen. The liquifying process requires energy also. I know a slick way to do this with water power, but it's not very efficient...
Liquid Hydrogen in your own backyard (Score:2)
I haven't tried this myself, but here goes. It should work for liquid air (mostly nitrogen), but the principle should hold for hydrogen as well. Take a pressure-safe vessel and put it in the creek. Take a paddle wheel and put it in the creek. Use the wheel to compress your gas-state hydrogen into the pressure vessel. This heats the hydrogen, but the heat is lost into the running water. When the vessel is full of high-pressure room temperature hydrogen, bleed the hydrogen out through a small valve. Hydrogen expands, cooling as it does. Liquid hydrogen then drips from your valve, with extensive loss to the air.
Pretty crappy, eh? But for liquid air, the loss doesn't matter much, and all you had to do was go down to the creek.
Feel free to tell me why this won't work, if anybody knows a reason.
wow, we'll here about this again very soon. (Score:2)
-The JungleBoy
--
"You never know when some crazed rodent with cold feet
might be running loose in your pants."
What about NOx? (Score:2)
Hydrogen can be obtained from non-polluting sources of power such as solar. But it would seem that a hydrogen-burning engine is going to produce some oxides of nitrogen, as long as you suck an oxygen-nitrogen mixture (air, of course) into the engine.
Re:As a matter of fact (Score:2)
There was a Canadian comedian (I forget who) I heard on the "This American Life" radio program saying that Canadians cannot let a comment about space flight pass by without saying "Canadian-made robotic arm! Canadian-made robotic arm! We made that arm!"
Re:But this will take oxygen out of the air (Score:2)
Answer: it combines with the hydrogen to become water vapor, which then falls on the ground as rain, where it sustains plants, which are busily converting carbon dioxide into oxygen.
As for "hundreds of rockets smashing through the stratosphere a day", compare the cross-sectional area of a rocket with the "surface area" of the stratosphere, say "gosh, that's a tiny ratio" and then stop to think how much worse all the petroleum fuels burned by airplanes are for the atmosphere.
Hell, next you'll be worrying about the fact that every launch slows the rotation of the Earth.
-
The Aurora Project (Score:2)
In the 90's, Reagan started the Aurora Project which was to create a hyper-sonic plane that could go from NYC to Tokyo in under 2 hours. The engines were scram jets.
The project was never really heard of since then, but oodles of initial money was dumped into it. Also, the US' fastest airplane, the SR-71 has since been retired with no replacement (some say that satelites make high/fast flying planes obsolete). IMHO I think we have a couple of these jets being used in our military.
I'm pretty sure I've got my facts straight on this. Anyone else heard of this?
Re:Umm. hello? (Score:2)
...
"Now it's used as holding area for illegal immigrants..."
Sooo... it's a bit hard to hit anything but illegal immigrants? Check.
Kevin Fox
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Re:USAF X-planes (Score:2)
Re:One problem with scramjets... (Score:2)
Re:The 'hydrogen is polution free' lie (Score:2)
Ryan
Re:USAF X-planes (Score:2)
Re:Some thoughts... (Score:2)
Re:Some thoughts... (Score:2)
Re:But this will take oxygen out of the air (Score:2)
Re:Finally! (Score:2)
Re:Some thoughts... (Score:2)
Re:The 'hydrogen is polution free' lie (Score:2)
Late 2000? (Score:2)
Re:Comparisons with Canada's Avro Arrow (Score:2)
Because of the slightly different climate, Canadians have a tendancy to take the probability of environmental extremes more seriously. +40C~-40C is supposedly considered US Mil Spec (104F ~ -40F). In Canada, it's considered outdoor equipment. I can exceed those exremes in one year driving around Alberta. Most years I can get +30~-40 just planting it in my backyard in Edmonton.
A friend ofmine has a story of some oilpatch equipment that froze up while stil inside of it's rated spec (rated to -45C; froze at -37C). He called down to the Texas company that supplied it to complain. The answer:
----In any event, there isn't a whole lot of conspiracy theory around the Avrow. The generally accepted theory is that the US needed many of those hot engineers for the Apollo project. That's where many of them went when the Arrow was tanked.
You didn't think that the States could get all the way to the moon without foreign help, did you?
As to the Avro enginering data being destroyed, it makes complete sense to me. The system was capable of doing stuff that the US was either incapable of, or unwilling to acknowledge being capable of. With most of the engineers going over to NASA associated work, the project was going to be, at best, mothballed for a long time. The last thing that you want is to have all this engineering data stacked in a warehouse somewhere just waiting for a Soviet Spy to cart it off to the Embassy. Far better to just trash the existing data, and rebuild from scratch later when/if you decide to do it again. Besides -- by the time they'd get around to restarting the project available technology could be expected to have advanced beyond whatever miracles they'd produced back then.
Pretty much the same thing was done with the Saturn 5 engines when NASA decided to go to the Space Shuttle. Although some people feel that it was done to prevent the ability to go back to non-reusable craft, I think that the security explanation is quite applicable here as well.
--
Another problem with scramjets... (Score:2)
And hydrogen is a pain in the ass. It has a higher specific impulse (thrust per mass of fuel) than any other fuel. That's why NASA is addicted to it. But it's density impulse (thrust per volume) sucks. Plus it's a hard cryogen. So you have to have a BIG, well insulated tank. That translates into major weight and major drag. This is OK on the ground, but it's really not such a great aerospace fuel. NASA insists on using it, as far as I can tell, mostly for reasons having to do with internal politics and organizational culture. (The Russians use kerosene or alcohol, which don't have as good a specific impulse but have a much, much better density impulse.)
Re:Free-fall ignition? Why? (Score:2)
Then, of course, it will heat up very rapidly and ablate. The point is, speed is not a problem, but materials may be.
Re:Free-fall ignition? Why? (Score:2)
They are claiming a sustainable velocity of Mach 7.6 or so, so you are correct. It would be prohibitive to expect Mach 20, but the fact is, it may pass through that velocity. The higher they go, the harder they fall, and velocity in a vacuum is only a function of potential, that is v= const* sqrt(h), h being height at apogee.
Re:Sounds like another Avro Arrow... (Score:2)
Sounds like another Avro Arrow... (Score:2)
scramjets (Score:2)
I remember an old story illustrating the differance a 50 or 100 year gap in technology makes. It was based on the idea of someone from 1920 trying to cope with a jet engine from 1970 drone with semi conductors, etc. interesting stuff.
just goes to show you what progress has been made
Re:ScramJet Space Plane? (Score:2)
Dude, the first rule of Flight Club is: Never talk about Flight Club! You also forgot the second rule of Flight Club, which is: Never talk about Flight Club.
Comparisons with Canada's Avro Arrow (Score:2)
A couple of people have mentioned the Arrow, presumably because this article appeared in a Canadian publication. However, it should be noted that nowhere does it mention any Canadian involvement in this scramjet research.
Also, I think comparisons with the Arrow are not very valid.
The Arrow was not a research project on new technology, it was an engineering project to produce a working fighter incerceptor that can enter active service.
It was a military vehicle, which meant that the market for it was relatively small. Furthermore, the Canadian requirements on the aircraft were so specialized that nobody else in the world was interested in such a beast.
On the other hand, the market for a working scramjet vehicle would probably be huge.
I'm not going to start speculating why the Arrow project was nixed, because that would probably ruffle a lot of Canadian feathers and start a flame war (it's probably Canada's biggest conspiracy theory).
Personally, I don't find it fishy that they cancelled the project; I do find it fishy that everything related to the project was destroyed.
--
ScramJet Space Plane? (Score:2)
Someone tell me these engines will enable the takeoff of a 'Personal* Space Plane'?
*I realize they wouldnt be TurboProp Planes like the local Flight Club - but I do mean a 'personal sized' Space Plane....
How does MACH7.6 compare with the the speed necessary to escape the atmosphere and head off into space? Obviously I realize the mass of the vehicle is relevant. What Im getting at is would it be possible that this technology could lead to what Im describing?
Re:Free-fall ignition? Why? (Score:2)
Pollution free? Maybe air pollution free, but I doubt that it is noise pollution free! At least it will fly so fast that you won't hear it for long, and by the time the noise hits, it will be long gone.
Re:Some thoughts... (Score:2)
It seems that is why they need to launch it into orbit first, then let it drop, so that it may ignite just before impact. Where is the path from this to a viable launch vehicle?
Re:Canadians and Australians... (Score:2)
Actually, just because one group is having problems doesn't mean that another group will not be able to approach the problems from a fresh perspective.
Southwest (Score:3)
I think this is an excerpt from the Southwest Airlines business model.
USAF X-planes (Score:3)
The X-15 plane [fiddlersgreen.net] (scroll down the page for program history), which flew for the first time in 1959, exceeded Mach 6, and flew over 100,000 ft.
The project was eventually cancelled, after a combination of spectacular crashes, exceedingly high costs, and the success of NASA's programs.
It is interesting that the X-plane pilots viewed themselves as the true masters of high-altitude and space flight. In their opinion, they were in control of their missions from start to finish, unlike the Mercury astronauts, who were simply strapped down on top of an explosive bottlerocket. Indeed, the first astronaut was a chimp!
Bob
Re:One problem with scramjets... (Score:3)
Little thing, but Ramjets definitely don't produce subsonic thrust. No moving parts, so without a strong compressed air input there's not a whole lot they can do... They're restricted to Mach 2 ish and above, too.
I was trying to find something on Google to back this up - hit Roger Ramjet instead :) Try http://www.britannica.com/bcom/eb/article/6/0,5716 ,64186+1+62599,00.html?kw=ramjet instead.
Whew! That was a close one... (Score:3)
Save the environment! Burn coal today!
---
Did you notice? (Score:3)
"The fastest known aircraft was the U.S. SR-71 Blackbird..."
The 'hydrogen is polution free' lie (Score:3)
So I wish I could stop hearing how burning liquid hydrogen is our savior as unlimited pollution free energy.
-- Greg
Forward thinking group (Score:3)
They also claim that they have set the world speed record for a chamaign cork (40 km/s) here (bottom) [uq.edu.au]
But this will take oxygen out of the air (Score:3)
Really.
There is a lot of it, surely. But when you get into the stratospheric levels there are delicate layers up there. The ozone layer is not just a simple 2 atom thick layer of ozone, there are support layers of other gases that help to keep it stable.
I agree, this technology is vastly superior to using fossil fuels for transportation purposes.
I simply hope that they work out the bugs and take the climactic effects into account, so the cure isn't worse than the disease.
Yes we have rockets all the time, but this is a question of scale. We do not have hundreds of rockets smashing through the stratosphere a day.
As a matter of fact (Score:3)
This is old, and written by an idiot. (Score:4)
On top of that, the article is so short on facts (not even any links to more information in the article body - don't these nitwits understand what hypertext is about?) that it's hardly worth reading. News for nerds? I think not.
--
Knowledge is power
Power corrupts
Study hard
The meaning of SCRAMJET (Score:4)
It means that the combustion occurs above mach 1. A normal ramjet is quite capable of operation above mach 1. However, the incoming air is slowed down and pressurized before combustion. In a scramjet, the air is still moving at supersonic speeds relative to the combustion chamber and fuel injectors. I've seen trying to keep a hydrogen/gasoline/whatever flame alive in those conditions (at the qantities of fuel burned by standard jet engines and more) compared to keeping a candle lit in a hurricane. It's difficult. No, REALLY. The benefit of a scramjet is that it can operate at REALLY high speeds. A ramjet loses too much energy slowing the air down to work above about mach 3-5. The concept is *similar* but fundamentally different.
More Details (Score:5)
One problem with scramjets... (Score:5)
Conventional turbine engines can of course be used, but they don't really like getting all the way up into the scramjet operating range. Thus, there has been a lot of research into engines that can work both as ramjets (subsonic combustion) and scramjets (supersonic combustion). Whereas they would still need to be moving around Mach 1 before they can start operating, it means conventional engines would be used for less of the flight, OR that the use of rocket combustion (bring your own oxygen) for the initial part of the flight without a serious weight problem. After all, the whole point with this whole thing is to avoid the rocket weight problem of having to bring your own oxidizer and just use the O2 in the air. Since for an H2-fuelled engine the oxygen is 8/9 of the weight, the advantage is obvious.
(Did I mention that I really hate that Slashdot don't let you use <SUB> and <SUP>?!?)
Umm. hello? (Score:5)
I'm worried, but I wanna see...
Kevin Fox
--
As Chief Wiggum would say... (Score:5)
"Thank God it landed in that smoking crater!"
This engine has no thrust.. (Score:5)
--