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This is absurd and scientific american sure has taken a fall from grace in order to believe it. Electrostatic "lifters" have been around for half a century. The
by superkuh 8y ago
This is absurd and scientific american sure has taken a fall from grace in order to believe it. Electrostatic "lifters" have been around for half a century. They are toys. They do not scale up. They cannot even lift themselves as their power supply or energy storage has to be on the ground with tiny wires going up to the lifter. There is absolutely no chance this can be called a 'plane'. It always has to be tethered with wire to deliver the power.
They were really popular with the UFO/Free energy crackpot crowds back in the late 90s and early 2000s.
- deleted 8y ago[deleted]
- upofadown 8y agoWell this particular plane runs off a battery...
- saidajigumi 8y agoAnd from TFA (sadly, the paper in Nature is referred to, but not properly cited) a main innovation is the development of a system that provides the required 40,000 volts from a battery in a form-factor amenable to small aircraft (think drone) usage.
- Varcht 8y agoWill make being a baggage handler pretty exciting.
- superkuh 8y agoDoes it? As far as I can tell it doesn't exist outside of the person's mind. Having played around with lifters myself using balsa, al foil, and a rectified neon sign transformer I just don't think the physics can work out. And there's no physical plane photos or videos to support otherwise. Until then I'm sticking with this being absurd. That said, ionization does have it's place in aircraft in terms of controlling attachment or detachment of turbulent airflow over wings. It can significantly improve fuel consumption by reducing drag. But it is not a viable propulsion source. At least not on Earth for things larger than a meter or so.
- hsnewman 8y agoHere is a time lapse of the flight: http://electricaircraft.mit.edu/wp-content/uploads/2018/11/actual_flight_time_lapse-300x168.jpg http://electricaircraft.mit.edu/wp-content/uploads/2018/11/a...
- eT8AZithxooKei6 8y agoLarger: http://electricaircraft.mit.edu/wp-content/uploads/2018/11/actual_flight_time_lapse.jpg http://electricaircraft.mit.edu/wp-content/uploads/2018/11/a...
- hnphillipj 8y agohttps://youtu.be/boB6qu5dcCw?t=128 https://youtu.be/boB6qu5dcCw?t=128 >But it is not a viable propulsion source. At least not on Earth for things larger than a meter or so. It's 5m wide
- superkuh 8y agoThanks for providing that. It does prove my point though. That plane is not flying at all. It is falling with style. The initial forward momentum is from the launch rail, not from the electrostatic propulsion.
- hnphillipj 8y agohttps://sci-hub.tw/https://www.nature.com/articles/s41586-018-0707-9 https://sci-hub.tw/https://www.nature.com/articles/s41586-01... see the top of page 534, figure b. You are correct that the initial forward momentum is from the launch rail, but the graph clearly shows that the ion engine provides thrust. Is the title of the HN submission misleading? Yes. Did the plane achieve flight with the ion engine alone? No. Was the plane able to maintain and gain altitude because of the ion engine? Yes. A step forward in the right direction but not as much of a breakthrough as the submission title would have you think. >As far as I can tell it doesn't exist outside of the person's mind. Based brah. I'm being serious when I say that I think HN needs more of this type of comment. They seem to love rigidity in comments, but not any bluntness or banter thrown in there.
- rubidium 8y agoIt's not entirely clear from the article, and I can't find the Nature publication yet... but I think you're wrong. It does carry it's own power supply and battery: "Finally Barrett used a computer model to get the most out of every design element in the aircraft, from the thruster and electrical system designs to the wires that ran through the plane. “The power converter, the battery, the caps and fuselage—everything was optimized,” Barrett says. “The simulations failed all the time. We had to make hundreds of changes.” In the end, they had the triumphant Version 2." Here's the researchers earlier publication (2015) on the physics behind it: http://rspa.royalsocietypublishing.org/content/471/2175/20140912 http://rspa.royalsocietypublishing.org/content/471/2175/2014... Edit: found some more material. No video of the actual plane yet. But the professor has a website here. http://electricaircraft.mit.edu/research/ http://electricaircraft.mit.edu/research/
- erbium 8y agoThis is such a typical Hacker News dismissal. The paper isn't even on Nature's website; please give it at least a week or a read before dumping on the author.
- aaron695 8y ago> This is such a typical Hacker News dismissal. And yet this thread is by far the best thread on the topic.
- _cs2017_ 8y agohttps://www.youtube.com/watch?v=boB6qu5dcCw https://www.youtube.com/watch?v=boB6qu5dcCw
- superkuh 8y agoThanks for providing that. It does prove my point though. That plane is not flying at all. It is falling with style. The initial forward momentum is from the launch rail, not from the electrostatic propulsion.
- erbium 8y agoAt 2:11 you can see it moving in a straight line.
- superkuh 8y agoNot shown: all the momentum imparted by the launch itself.
- erbium 8y agoShown: you, not reading the paper. https://sci-hub.tw/https://www.nature.com/articles/s41586-018-0707-9 https://sci-hub.tw/https://www.nature.com/articles/s41586-01...
- thinkcontext 8y agoFor the Nature paper they compared unpowered vs powered flight. Unpowered got about 10m, powered got to 60m, the length of their test facility.
- tzs 8y agoIn that clip it is not slowing down, showing that the ion drive is generating sufficient thrust to sustain flight. It's irrelevant that it used assistance to initially reach that speed.