David Hambling's article in Wired Magazine,"‘Impossible’ Device Could Propel Flying Cars, Stealth Missiles" sounds more like we may have just figured out how to build UFO-style devices. "Getting to Australia in 4 hours" and to ... "the moon in 4 days with a 40 tonne payload"? Oh, and silently with no visible thrust and also no need for wings or anything like that either.
You know, all I have to say about this for now is ... Rave in Space! Rave in Space!
The Emdrive is an electromagnetic drive that would generate thrust from a closed system — “impossible” say some experts.
‘Impossible’ Device Could Propel Flying Cars, Stealth Missiles
To critics, it’s flat-out junk science, not even worth thinking about. But its inventor, Roger Shawyer, has doggedly continued his work. As Danger Room reported last year, Chinese scientists claimed to validate his math and were building their own version.
Shawyer gave a presentation earlier this week on the Emdrive’s progress at the CEAS 2009 European Air & Space Conference. It answered few questions, but hinted at how the Emdrive might transform spaceflight — and warfare. If the technology works, that is.
The heart of the Emdrive is a resonant, tapered cavity filled with microwaves. According to Shawyer, a relativistic effect generates a net thrust, an effect confirmed by various Emdrives he has built as demonstrations. Critics say that any thrust from the drive must come from another source. Shawyer is adamant that the measured thrust is not caused by other factors.
While the argument over the drive’s impossibility continues, so does the engineering work. The problem is that nobody wants to talk about it. Even Shawyer gives little away. Last year, professor Yang Juan of the College of Astronautics at Northwestern Polytechnical University (NPU) in Xi’an was happy to confirm that they were building an Emdrive which would be tested by the end of the year. But following the publication of this news in Danger Room, the situation changed. I was informed that the publicity was very unwelcome, especially any suggestion that there might be a military application. (Yang had previous published a study on the use of plasma as a weapon against low-orbiting satellites. [.pdf]) No further information has been forthcoming, and no Chinese papers have been published on the Emdrive, though Yang has recently published work on (unrelated) microwave plasma thrusters (.pdf).
Shawyer asserts that work is also being carried out in France, Russia and in the United States by a major aerospace company. But he cannot provide details beyond vague promises of “significant progress [that] has been made in both theoretical and experimental work, within these groups.” He also asserts that the British National Space Centre is said to be reviewing the Emdrive. Again, no details.
The CEAS 2009 paper outlines recent progress and plans. Previous thrusters generated relatively modest forces; the latest version now being built is based on a cooled superconductor and should generate more than 300 pounds of thrust for a 6-kilowatt input, Shawyer promises. (But does not yet appear to have done so.) The plan is to mount four of these thrusters on an unmanned demonstration vehicle that will weigh about 1,000 pounds. The craft will have no wings: It will be supported by the Emdrives and propelled by jet engines to about 230 knots. It will be capable of vertical takeoff and hovering silently in place. If successful, it will be adapted as a personal transport -– your very own flying car.
In the longer run, perhaps 10 years, Shawyer envisages a hybrid spaceplane using Emdrive technology — see the photo above of a 2-meter scale model. The idea is a craft capable of making the 10,000-mile run from London to Sydney, Australia in under three hours … or taking a 40-ton payload on the moon in about four days.
Aeronautical engineers have been dreaming of such a craft for decades; none have ever panned out. The theoretical advantage of the Emdrive spaceplane compared to rockets is that it allows a slow ascent with low acceleration rate. There is also no telltale rocket exhaust plume, and this may be the source of some of the interest. At present, the launch of a ballistic missile anywhere on Earth can be immediately spotted from space. An Emdrive-based launch system would be undetectable and could arrive from any direction, leaving the target of an attack no way of knowing who to retaliate against.
This is the kind of factor that might drive governments to put money into Emdrive projects. An investment in contested science is not a probable winner — but the payoff could be a big one.
Photo: Roger Shawyer/SPR Ltd
ALSO:
Chinese Say They’re Building ‘Impossible’ Space Drive
Chinese researchers claim they’ve confirmed the theory behind an "impossible" space drive, and are proceeding to build a demonstration version. If they’re right, this might transform the economics of satellites, open up new possibilities for space exploration –- and give the Chinese a decisive military advantage in space.
To say that the "Emdrive" (short for "electromagnetic drive") concept is controversial would be an understatement. According to Roger Shawyer, the British scientist who developed the concept, the drive converts electrical energy into thrust via microwaves, without violating any laws of physics. Many researchers believe otherwise. An article about the Emdrive in New Scientist magazine drew a massive volley of criticism. Scientists not only argued that Shawyer’s work was blatantly impossible, and that his reasoning was flawed. They also said the article should never have been published.
"It is well known that Roger Shawyer’s ‘electromagnetic relativity drive’ violates the law of conservation of momentum, making it simply the latest in a long line of ‘perpetuum mobiles’ that have been proposed and disproved for centuries," wrote John Costella, an Australian physicist. "His analysis is rubbish and his ‘drive’ impossible."
Shawyer stands by his theoretical work. His company, Satellite Propulsion Research (SPR), has constructed demonstration engines, which he says produce thrust using a tapering resonant cavity filled with microwaves. He is adamant that this is not a perpetual motion machine, and does not violate the law of conservation of momentum because different reference frames apply to the drive and the waves within it. Shawyer’s big challenge, he says, has been getting people who will actually look into his claims rather than simply dismissing them.
Such extravagant claims are usually associated with self-taught, backyard inventors claiming Einstein got it all wrong. But Shawyer is a scientist who has worked with radar and communication systems and was a program manager at European space company EADS Astrium; his work rests entirely on Einstein being right. The thrust is the result of a relativistic effect and would not occur under simple Newtonian physics. Many have dismissed his work out of hand, and British government funding has ceased. He has had some interest from both the United States and China. Now the Chinese connection with the Northwestern Polytechnical University (NPU) in Xi’an seems to have paid off.
"NPU started their research program in June 2007, under the supervision of Professor Yang Juan. They have independently developed a mathematical simulation which shows unequivocally that a net force can be produced from a simple resonant tapered cavity," Shawyer tells Danger Room. "The thrust levels predicted by this simulation are similar to those resulting from the SPR design software, and the SPR test results." What’s more, Shawyer says, NPU is "currently manufacturing" a "thruster" based on this theoretical work.
The NPU have confirmed that they have reproduced the theoretical work, and are building a demosntration version of the Emdrive.
Needless to say, independent confirmation is a big deal — though many will want to see it published in a peer-reviewed journal. Even when it is, I doubt the controversy will subside. Prof. Yang has plenty of experience in this type of area, having previously done work on microwave plasma thrusters, which use a resonant cavity to accelerate a plasma jet for propulsion. While the theory behind the Emdrive is very different, the engineering principles of building the hardware are similar. The Chinese should be capable of determining whether the thruster really works or whether the apparent forces are caused by experimental errors.
The thrust produced is small, but significant. Shawyer compares a C-Band Emdrive with the existing NSTAR ion thruster used by NASA. The Emdrive produces 85 mN of thrust compared to 92 for the NSTAR (that’s about one-third of an ounce), but the Emdrive only consumes a quarter of the amount of power and weighs less than 7 kilos, compared to over 30 kilos. The biggest difference is in propellant: NSTAR uses 10 grams per hour; the Emdrive uses none. As long as it has an electricity supply, the Emdrive will keep going.
The possibilities are phenomenal: Instead of going out of service when they run out of fuel, satellites would have greatly extended endurance and be able to move around at will. (We wouldn’t have to shoot them down because of the risk from toxic fuel either.) Deep space probes could go further, faster –- and stop when they arrive. Shawyer calculates that a solar-powered Emdrive could take a manned mission to Mars in 41 days. Provided it works, of course.
What will China do with the technology? It may be relevant that professor Yang is not unknown in military circles, having published a paper called "Plasma Attack Against Low-Orbit Spy Satellites."
Meanwhile, what about the American interest? Shawyer told me that "the flight thruster program is on hold for the present. [O]nce the U.K. government had provided an export license for a U.S. military application, the major U.S. aerospace company we had been dealing with stopped talking to us. "
The company may have decided that the Emdrive could not work. If they’re wrong, China has at least a year’s head start in a technology that will dominate space and make previous satellites as obsolete as sailing ships in the age of steam.
(Picture: SPR Ltd)
When Chinese scientists claimed that they had validated the math behind the "impossible" Emdrive — and are building their own demonstration model — it brought a predictable storm of protest. Many said it can’t be true. Others objected that the only proof would be to build an actual "Emdrive" that converts drive converts electrical energy into thrust via microwaves. Roger Shawyer, inventor of the Emdrive, has built several. The video appears to show one of them in action.
The drive allegedly produces a fraction of an ounce of thrust. That may not seem much, but it’s comparable to existing ion engines used on deep space probes. Seeing is not necessarily believing, however. The video could be anything, and even if it is real it proves nothing, as British space blog Rocketeers points out:
Here’s my take on it. It "works" after a fashion (actually generates thrust), but not in the way that Shawyer thinks it does. It’s actually a form of Asymmetric Capacitor Thruster (ACT), which generates thrust by the Biefeld-Brown effect — charged metal surfaces ionise the surrounding air by corona discharge, and create an ‘"ion wind" which pushes the apparatus along. Good for the continued integrity of the laws of physics, but bad for space applications of the EmDrive, because in a vacuum it would do precisely nothing.This is much the same explanation for those supposed antigravity "lifters" which were popular a few years back. However, Shawyer claims that this and other effects have been taken into account.
"Stray electromagnetic effects were eliminated by using different test rigs, by testing two thrusters with very different mounting structures, and by changing the orientation by 90 degrees to eliminate the Earth’s magnetic field," he writes. "Electrostatic charges were eliminated by the comprehensive earthing required for safety reasons, and to provide the return path for the magnetron anode current."
Independent testing looks like the only sensible solution. But if the basic science is not accepted, who’s going to waste time testing something that’s impossible? I’d like to see this resolved one way or another; perhaps the definitive answers will come from the Chinese work at the end of this year.
Meanwhile, Shawyer will be presenting a paper at the 59th International Astronautical Conference in Edinburgh this week. He might be able to reveal some more results from his own work, but making converts in the world of commercial spaceflight looks like being an uphill struggle.
UPDATE: When I asked him about the possibility of "ion wind" being the real cause of thrust, Dr Shawyer patiently explained that it had been addressed at a very early stage:
"Air currents from whatever source were eliminated in the first Proof of Concept project by testing the experimental thruster mounted in a hermetically sealed box. The experiment was reviewed and accepted by professional government scientists." [The research was being supported by the British government at the time.]
He also points out that real ion drives need much higher voltage and that "Anyone who thinks they can create grammes of thrust from ion wind at the voltages we work at clearly doesn’t understand physics." He does not believe a vacuum chamber test would show anything, as ion drives function in a vaccum and there would still be the question of wehther some ionised material was somehow being ejected. However, the hermetically sealed box test should have negated that possibility.
This seems to strengthen the case for independent testing. But would it convince the skeptics? I suspect that even if the Emdrive was propelling a space probe around the solar system there would still be some saying "Yeah, it works but it can’t be working the way he says it does…"I'm just so shocked, and yet not-so-shocked by this at the same time. I mean is YouTube to blame for this? I've seen so many back-yard demonstrations on magnetic free energy and Bob Lazar talking about S-4, etc. I guess it would just be a matter of time before someone decided to take them seriously.
Was hoping it wouldn't be the Chinese government though.
I would guarantee that someone figures out real quick exactly how to make one work (because this technology has already been discovered/invented) and I'd bet the race is on.
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