Slashdot Mirror
HyShot Scramjet Test Declared a Success
An anonymous reader writes: "ABC news is reporting
that analysis of the flight data from the recent
HyShot scramjet test (covered by Slashdot
previously) suggests that the test was successful and that the engine achieved combustion in flight after reaching Mach 7.6. The University of Queensland is also reporting the news."
BBC story
University of Queensland researchers today (August 16) claimed success for the world`s first flight test of supersonic combustion, the process used in an air-breathing supersonic ramjet engine, known as a scramjet.
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"Our honest understanding from preliminary data is that the experiment worked," said international HyShot(TM) program leader Dr Allan Paull, of UQ's Centre for Hypersonics.
"We received data for the full length of the 10-minute flight. All indications are that supersonic combustion occurred. We'll now be submitting the results to international peer review."
On July 30 a safe and successful launch of a Terrier Orion Mk 70 rocket containing a scramjet payload was held at Department of Defence's Woomera Instrumented Range, 500km north of Adelaide, in the South Australian desert.
The aim of the HyShot(TM) program is to provide the world's first in-flight tests of scramjet technology, validating experiments held in ground test facilities.
While scramjets raise the possibility of Sydney to London flights in two hours, they are set to revolutionise the launch of small space payloads, such as communications satellites, by substantially lowering costs. They have the added benefit that they do not even have to carry most of their propellant as they use oxygen from the atmosphere.
University of Queensland Vice-Chancellor Professor John Hay congratulated the international HyShot(TM) team on its success, which he said put Australia at the forefront of this new technology and enhanced the country's international prestige in space research.
"It's a magnificent example of international collaboration, involving researchers from Australia, the United States, Britain, France, Germany, Korea and Japan," he said.
Professor Hay is chair of the Group of Eight, Australia's leading research-intensive universities which produce the majority of Australian scientific research.
"Australia has proved we can develop this technology at a fraction of the cost of overseas programs. We must now build on success and secure the program in Australia so the intellectual property is not lost to the country. The danger is that the program could move offshore.
"Dr Paull has received approaches from top Australian researchers based in NASA, Boeing and other organizations keen to return to Australia to work on the HyShot program if suitable funding is available."
Professor Hay said these researchers were trained at UQ's Centre for Hypersonics, which is directed by Professor Richard Morgan. This is the largest group of hypersonics researchers in Australia and the largest University-based hypersonics group in the world, with some of the world's most advanced equipment for simulating velocities of eight times the speed of sound to 50 times the speed of sound, the speeds experienced by reentry vehicles such as space shuttles and after interplanetary missions.
"HyShot(TM) provides a significant opportunity for Australia to reverse the brain drain," Professor Hay said.
Dr Paull said he was negotiating with various groups to conduct an extensive, ongoing and advanced $50 million program of six flights over five years, leading to a free flying scramjet engine. The program would provide information to determine a cost effective launcher based in northern Australia to launch small, lightweight satellites.
"The program has generated lot of international interest," he said. "We currently don't have funding for future flights, but the Japanese, through NAL, have provided funding to build a new payload." Dr Paull will visit international collaborators in the next few weeks for talks on future flight programs.
The recent HyShot(TM) launch was designed to take the scramjet engine to a speed of Mach 7.6 (or more than seven times the speed of sound) for the experiment, using a Terrier Orion rocket. The rocket and payload reached an altitude of 314km before the rocket was configured to fly in a new trajectory pointing the payload back down to earth. The flight experiment took place within only the last few seconds of the flight, lasting almost 10 minutes.
After the Terrier booster had finished its work and subsequently fell 5km downrange, the Orion continued on with the scramjet payload and impacted some 370km downrange of the launch site, very close to the nominal impact point predicted by the scientists.
Radar and four sets of telemetry (radio) tracked the flight. One telemetry station was at Woomera Instrumented Range, while three telemetry officers were stationed at three points of a triangle more than 300km downrange in the middle of the desert. They not only captured the final seconds when the experiment occurred, but one site, to its credit, also captured all but the first 15 seconds of the flight.
Dr Paull said this was a "tremendous achievement."
"All those who were involved in producing this most exciting result are to be commended," he said.
After everyone had gone home, the researchers faced a nail-biting wait for the telemetry officers to come in from the dust with their precious data, before analysis could occur.
Dr Paull said everything appeared to have worked to plan, with only a minor glitch of a horizon sensor to turn the rocket failing half way through the flight, but a backup system had kicked in, using all their software capabilities.
Astrotech Space Operations senior engineer Dr Morgan Windsor said the job that so few with so little undertook was incredible and the fact that it worked was almost anti-climactic.
"Allan said a number of times that just getting the payload launched was a great success and indeed it was. But now that he has achieved combustion in flight this represents a huge accomplishment and a first internationally. I am so pleased that I had the opportunity this late in my career to support UQ, Allan and his team and have not sensed a greater feeling of accomplishment," Dr Windsor said.
Professor Hay and Dr Paull thanked all consortium partners and sponsors, in particular:
Astrotech Space Operations/DTI
QinetiQ
Defence Science and Technology Organisation (DSTO)
Defence Corporate Support
Aircraft Research and Development Unit, Australian Defence (ARDU)
the Australian Research Council
NASA Langley Research Center
NAL (National Aerospace Lab. Japan)
AFRL (Air Force Research Laboratory, USA)
DLR (German Aerospace Center)
Seoul National University
DISR
Australian Space Research Institute (ASRI)
BAE Systems Australia
Alesi Technologies
GASL
Aerospatiale Matra
NQEA
UniQuest
Institution of Engineers Australia (Queensland)
Jet Air Cargo
AECA
Luxfer Australia
Media contacts:
UQ Communications - Jan King, telephone 0413 601 248 or 07 3365 1120, Peter McCutcheon, telephone 07 3365 1088 or 0413 380012
Hyshot(TM) stories are available at www.uq.edu.au/hyshot. Photos, attributed to The University of Queensland (photographer Chris Stacey), can be downloaded from http://www.uq.edu.au/news/hyshot/hyshot-gallery.p
There's a ton of photos at http://photos.cc.uq.edu.au/HYSHOT/ and also at http://www.mech.uq.edu.au/hyper/hyshot/HyShot_phot os.html. The former link has some friggin huge jpegs.
There is also a page about the HyShot program itself at http://www.mech.uq.edu.au/hyper/hyshot/
It's not how fast, but how did they fly that fast.
The Scramjet theory has to have occurred. Which is basically an engine with no moving parts. The intake air has to hit the fuel so fast, and at such high density that some sort of "Critical Mass" combustion takes place that produces more thrust that drag of the air molecules hitting the craft at about 10kph.
When you're on a shoe-string budget, it's hard to figure out if that really happened. It'll take a much more expensive project to figure this out for sure, hence, NASA's much more expensive project.
Who needs this anyway, with
Sydney's Mardi-Gras going bankrupt!
Hello Frisco!
Acceleration, on the other hand, is a problem. Ever been in a jet? I don't think it'll be worse than that.
Big difference between speed and acceleration. What's Earth's orbital velocity again?
You were right, though, you're no physicist.
Untrue. Sound travels slower because the air is colder, not thinner. The speed of sound in the Earth's atmosphere is proportional to the square root of the temperature, nothing else. http://www.allstar.fiu.edu/aero/mach.htm
Here's an atmosphere simulator where you can pick an altitude and see the speed of sound. As it says, "the speed of sound depends on the temperature and the gas," not on pressure.
It's only a high rate of acceleration that causes passengers to experience excessive G force. Once you've reached Mach 7, so long as you remain at a constant velocity nobody should notice how fast you're going.
Assuming you weren't trolling:
Mach 7.6 is a speed, not an acceleration. A hypersonic passenger vehicle will presumably travel with moderate acceleration until reaching high speed.
At 1/2-earth-gravity acceleration, you get one sea-level Mach number per minute, more or less, so you'll be at Mach 7.6 a few minutes after launch.
2*3*3*3*3*11*251
Note that the figures at
fas.org indicate that the speed of the Minuteman III at burnout is approx. Mach 23.
What you do have the potential for (given significant further progress) is very fast cruise missiles, not ICBM's.
John_Chalisque
Mach is a measure of speed relative to the speed of sound at a given elevation, it is not a measure of acceleration. So, at sea level, Mach 7.6 is roughly 5800mph (~2600m/s), but at 25000ft, where the air is thinner, Mach 7.6 is about 5000mph (~2250m/s).
The gravitation of earth (ie, the amount of force we feel from gravity) is 9.8m/s^2. So, a constant 1G force (which the body won't find too uncomfortable) would accellerate a body to 2250m/s in about four minutes... If a genter push is desired, say .5G, that level of acceleration would need to be maintained for a bit over seven and a half minutes...
Unless, of course, my physics is rusty.. :^)
there will probably be "low-speed" versions for shorter distances
Probably not. To understand why requires some knowledge of how a scramjet differs from a normal turbofan engine. There are no spinning parts in a scramjet or ramjet engine. The (sc)ram engine requires a strong standing shock to me maintained in the intake. This standing shock replaces the compressor section of a normal turbo fan. There is a minimum speed which will produce a sufficiently strong, stable shock that will allow this to work.
The SC part is for supersonic combustion which makes that standing shock also replace the combustor portion of the turbo fan. Chemical reactions and transonic fluid dynamics can interact in very complicated ways. This can make this supersonic combustion unstable. The best way to stabilize it is to go faster and increase the strength of the shock.
So, to sum up, operating scramjets at lower speeds is more difficult, so if anything, we will probably see them operating at the highest possible speeds that the airframe and aerodynamics will allow.
One of the interesting footnotes from aviation is the first attempt at breaking the sound barrier. As you approach the speed of sound turbulence increases dramatically. However, when you break it you are in a new aerodynamic regime and suddenly the turbulence plummets. A very pleasant surprise to Chuck Yeager, the first supersonic pilot.
t ml
You can find more information about the "Wall of Air" that was believed to prevent supersonic flight, as well as Yeager's breaking on the barrier here:
http://www.capstonestudio.com/supersonic/main.h
Life is short: void the warranty.
At a constant 1G acceleration, you'd hit Mach 7.6 in about 4 minutes and travel about 260 KM. The Space Shuttle goes supersonic within 75 seconds of liftoff, so it really doesn't take too long. I think by the time the boosters drop off (2-1/2 minutes) it's doing Mach 3 or better.
The X-15 hit Mach 6.72, and its maximum burn time was under 5 minutes (it was a rocket plane though), so it makes sense for something like a hypersonic engine to be used for real flights, even NY-LA would be practical...under 1 hour door-to-door, no need for a crappy airline meal! The SR-71 has already done NY-LA in about 1 hour at Mach 3.5.
A man's reach must exceed his grasp, or what's an erection for?
As I read the comments, it seems that some people don't get the implications. In a normal jet engine the flow has to be slowed to less than Mach 1 for compustion to occur. Faster, and it goes out. This limits the range of velocity that can be attained. So, there is a range of velocity that can only be attained with rockets. With a working Scramjet it becomes possible to fly most of the way to orbit. From an energy consideration, once you are in low earth orbit you are half way to anywhere in the solar system and can use low acceleration, high efficency engines to get anywhere.
Scramjets are the realistic key to space exploration.
Eschew Obfuscation
Our monkey brains can't really appreciate the size of this Earth. Circumference = 24,000 miles. Mach 7.6 = 5000 mph. So it'd take about 5 hours to circumnavigate the globe -- or about 2.5 hours to reach the opposite point on the other side of the world.
Depending on lift ability, this could have fascinating implications for rapid-response troops.
But more importantly, it's potentially an excellent way to lower costs to get things into orbit. And air travel is all well and nice, but the future is in space travel, at least to LEO.
The Mongrel Dogs Who Teach
Bzzzt. But thank you for playing. Since forces are dependent on acceleration, moving at constant speed is indistinguishable from being at rest. That's not even Einstein -- that's Galileo.
Bzzzt again. This just isn't your day. First, modern physicists don't even talk about mass increasing as velocity increases. Mass is mass is mass; ie., what used to be called "rest mass". The observed kinetic energy increased with velocity, of course. But we don't use relativist mass because it implies things like, "Oh, Newton's laws are OK if you just put a factor of gamma in", which is not true. It can be shown that in fact, there would be two relativistic masses, a "parallel component" one and a "transverse component" one. This complicates the idea of mass and force so much it's of no use whatsoever.
Second, even if your mass seems to increase as measured by an observer, it wouldn't for you... All of your molecules will be traveling at the same speed, so each sees the others at rest and therefore, by the first principle of relativity, can see no mass effect.
Third -- and now I'm just being obnoxious -- you seem to confuse "mass" and "weight".
The Mongrel Dogs Who Teach
The equations you will find in most aerospace texts go as follows. There are, aparently, more complicated formulas but for 99% of the cases these are accurate.
a = speed of sound (m/s)
v = velocity of vehicle (m/s)
M = mach number
G = gamma - gas constant (1.4 for air)
R = gas constant (can't remember units but =288 for air)
T = Temperature (kelvin)
a = sqrt(GRT)
M = v/a
speed of sound is directly related to temperature and type of fluid.
No. Years of Star Trek have mislead people by analogy, but the "sonic boom" is not the sound of you piercing the sound barrier. It's the result of a massive spike-and-fall of pressure across your ears. You are right that it comes from a superposition of pressure maxima (a "piling up") but that happens along a cone of air.
Without touting my own horn too much -- and believe me, there are equally good or better animations -- but I have a set of animated GIFs that show this.
The Mongrel Dogs Who Teach
If you're flying at about 5,000 mph, you could cover the London-New York distance in about 40 minutes. Add a bit more time for acceleration and decceleration.
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