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Final NASA Eagleworks Paper Confirms Promising EM Drive Results (hacked.com)
An anonymous reader quotes a report from Hacked: Earlier this month Hacked reported that a draft version of the much expected EmDrive paper by the NASA Eagleworks team, had been leaked. Now, the final version of the paper has been published. The NASA Eagleworks paper, titled "Measurement of Impulsive Thrust from a Closed Radio-Frequency Cavity in Vacuum," has been published online as an open access "article in advance" in the American Institute of Aeronautics and Astronautics (AIAA)'s Journal of Propulsion and Power, a prestigious peer-reviewed journal. The paper will appear in the December print issue of the journal. The final version of the paper is very similar to the leaked draft. In particular, the NASA scientists confirm the promising experimental results: "Thrust data from forward, reverse, and null suggested that the system was consistently performing at 1.2 +/- 0.1 mNkW, which was very close to the average impulsive performance measured in air. A number of error sources were considered and discussed." The scientists add that, though the test campaign was not focused on optimizing performance and was more an exercise in existence proof, it is still useful to put the observed thrust-to-power figure of 1.2 mN/kW in context. "[For] missions with very large delta-v requirements, having a propellant consumption rate of zero could offset the higher power requirements. The 1.2 mN/kW performance parameter is over two orders of magnitude higher than other forms of 'zero propellant' propulsion, such as light sails, laser propulsion, and photon rockets having thrust-to-power levels in the 3.33--6.67 uN/kW (or 0.0033--0.0067 mN/kW) range."
In other words, a modest thrust without having to carry fuel can be better, especially for long-distance space missions, than a higher thrust at the cost of having to carry bulky and heavy propellant reserves, and the EmDrive performs much better than the other "zero propellant" propulsion systems studied to date.
It's Steorn all over again.
Apart from the open process and independently verified results
The most implication of experimentally confirming these observations would be for our fundamental physical models. Nobody can really say what it means, but it is potentially as important as the discovery of spectral lines, which was instrumental for the development of quantum theory.
As with most discoveries in fundamental physics, the actual applications are often unpredictable and rarely match the initial expectations. If anyone tells you they know, they are talking out of their asses.
Unlike Tesla and its autopilot, EM Drive actually seems to work.
Are you serious? If the EM drive works we are at the gates of a major revolution in Physics (as in 'our understanding of Physics'). First we should have to understand how it works, tinker with it till the smallest-lightest-efficientest designs emerge. In parallel, other people would be trying to determine WHY it works. That's a much bigger task, that requires a rewriting of most Physic's textbooks. When we have a new theory that explains the EM drive, then probably still better drives can be designed, perhaps using other kinds of radiation.
What I'm driving at, is that discussing how possibly adequate or inadequate this EM drive is to space travel is like discussing the usefulness of electricity when good old Thales started rubbing amber pieces against animal skins.
Rome taught me patience and assiduous application to detail. Virtues which temper the boldness of great, general views.
Just because you don't understand how it works doesn't mean it's instantly a "perpetual motion machine". I sincerely doubt it's creating energy from nothing.
Seriously. Top scientists don't know how it works yet. What makes you think you have the answers?
BeauHD. Worst editor since kdawson.
You appear to have committed an error, here. That P=W/t converts to P=fv implies nothing about being over unity past a certain speed, or under unity below it. It's easy to see how a layperson's overreading of the words would yield such a view, however.
Considering your views on social issues, I'm unsurprised.
> The actual methodology generating the thrust isn't clearly explained, 95% of this paper is about the testing conditions
Well duh, this paper is about proving existence. It's a physical test, it doesn't have to explain why it works. If the models don't fit reality then it is the models that are wrong, not reality. Hence the details about the test infrastructure. That results don't have to make sense, they just need to show that existing models are invalid.
Black holes emitted radiation back in the 19th century. Did you know that?
Oddly enough, nothing in pre-20th century physics allowed for that to happen.
It is just barely possible we're about to begin a 21st Century revolution in physics comparable to the one(s) in the 20th Century (Relativity, QM).
Or not. But till you run the experiment (noone is stopping you, you know), your repeated "it doesn't work" comes across rather like a child putting his fingers in his ears and chanting "I can't hear you" over and over....
"I do not agree with what you say, but I will defend to the death your right to say it"
No. You are not getting it. View the result of the experiment not as a violation of CoM but rather as "unexplained momentum transfer". You continue to assume that CoM holds and go about figuring out mysterious way that the EM drive is imparting some of its momentum into its surroundings.
Instead of engineers they need to get some scientists involved because the paper shows a total focus on simply measuring the thrust and zero scientific investigation to investigate the cause of the thrust.
Yeah I know. What an absurd thing to do in a paper titled: "Measurement of Impulsive Thrust from a Closed Radio-Frequency Cavity in Vacuum"
Have you ever considered that there may be other teams doing research on this an this just happens to be the first paper out? Damn them for not doing everything at once and reaching all conclusion at the same time.
which suggests a position accuracy of ~1nm which is less than the size of an atom
Might want to double check that, I'm pretty sure atomic radii are measured in picometers.
They can be measured in any unit you like, but the typical size of an atom is in between 30 and 300 pm. So GP is wrong: 1 nm is greater (not less) than the size of an atom, but it's in the ballpark.
https://en.wikipedia.org/wiki/...
If it weren't for deadlines, nothing would be late.
While the OP did indeed ask for practical propulsion applications, the implications of a change in physics theory is enormous, as his example illustrates quite well.
Spectral lines led to the realization that energy is not continuous, but discrete in very small units which can interact with matter, and by inverting that principle, small changes to matter can result in large changes to energy. That directly led to the theory behind semiconductors, enabling transistors and other solid-state electronics, ultimately leading to the entirety of modern electronics technology.
Similarly, verifying a repeatable violation of the laws of physics means that those laws are inaccurate. By refining the theory to fit the new observations, we can also revisit our assumptions about what is possible using electromechanics. To address OP's question, energy, not fuel, becomes the limiting factor in propulsion. That in turn alters the theory of rocketry, which affects the limits of human expansion, providing new areas of study for anthropology and sociology.
However, the scope of affect also lies beyond rocketry. If EM can produce thrust, we may be able to miniaturize the device to a nanotechnology scale, as a new tool for nanomachines. As one example off the top of my head, we may be able to produce self-controlled materials that change shape by rearranging microscopic structures, similar to how animal muscles work by moving actin and myosin molecules.
In short, the actual application of any discovery is the increase in understanding of how the universe works, and from that we can derive advances in technologies.
You do not have a moral or legal right to do absolutely anything you want.
You vastly underestimate the situation. The EM drive could be the Michelson-Morley experiments of the 21st century. If you don't recognize that, those are the series of experiments whose "inexplicable" data led to Einstein's discovery of relativity.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
They didn't measure the thrust at that speed, they measured it under stationary conditions.
Your constant-thrust assumption can be what is wrong here.
On the other hand, if thrust goes down when speed goes up, then what use is that drive?
I also wonder how the other 'fuel-less' thrust engines behave in this respect. Do those go into 'over unity'?
Clearly not, I would say. So why would this one...
"Trump!!", the new Godwin.