04-10-2021, 01:15 PM
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#11 (permalink)
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Thalmaturge
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I think the multi rotors here are just supposed to be enough to get it high enough to accelerate/climb as a fixed wing plane. I'd be surprised if this thing ever went much higher than 50-75' on the rotors. And the reverse for landing, of course.
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04-10-2021, 03:09 PM
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#12 (permalink)
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Master EcoModder
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Quote:
Originally Posted by redpoint5
I don't know the fascination with multirotors.
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My guess would be no swashplates. All the control is in software. Regular helicopters can't do that thing where they flip on their back.
Plimp is located in Seattle, WA. Jetoptera is in Edmonds, WA; a short flight North. I want to see a Jetoptera powerplant in a Plimp airframe.
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04-10-2021, 03:24 PM
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#13 (permalink)
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Human Environmentalist
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Quote:
Originally Posted by freebeard
My guess would be no swashplates. All the control is in software. Regular helicopters can't do that thing where they flip on their back.
Plimp is located in Seattle, WA. Jetoptera is in Edmonds, WA; a short flight North. I want to see a Jetoptera powerplant in a Plimp airframe.
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Lighter than air, now that's where the action's at. Sure, not fast, but efficient when the main objective is to avoid congestion.
Make it H2 rather than He, and you might get something fairly compact, too. Both gasses are fantastic at thermal conductivity, so cooling the electrics would be easily accomplished by enclosing them in the envelope.
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04-10-2021, 04:41 PM
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#14 (permalink)
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Steam has lift comparable to Helium. Nothing beats hot Hydrogen. So.... a hot hydrogen rigid wrapped with a limp steam blanket.
https://en.wikipedia.org/wiki/Thermal_airship
The Flying Kettle Project - balloons and airships filled with steam!
The other half of the equation is light-weighting. R. B. Fuller contended that as size increases the ratio becomes more favorable. His Cloud Nine design was an open framework that maintained a 1 degree temperature difference but let the wind blow through it.
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04-10-2021, 05:03 PM
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#15 (permalink)
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Human Environmentalist
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Quote:
Originally Posted by freebeard
Steam has lift comparable to Helium. Nothing beats hot Hydrogen. So.... a hot hydrogen rigid wrapped with a limp steam blanket.
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Nothing does beat hot hydrogen (vacuum). Not sure if your correctness was intended or not, but I attribute meta brilliance to you.
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04-10-2021, 05:34 PM
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#16 (permalink)
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Master EcoModder
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I blame Arthur C. Clarke en.wikipedia.org/wiki/A_Meeting_with_Medusa
edit:
...and Playboy where I read that forty years ago in 1971,
Quote:
Not sure if your correctness was intended or not, but I attribute meta brilliance to you.
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I should be more gracious. You're right, of course. ![Smile](/forum/images/smilies/smile.gif)
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Last edited by freebeard; 04-10-2021 at 10:29 PM..
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04-10-2021, 08:30 PM
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#17 (permalink)
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Corporate imperialist
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It's starting to sound like a typical electric vehicle. It does great in a real specific set of circumstances, then out side of that, not so much.
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04-11-2021, 12:50 AM
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#18 (permalink)
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Quote:
Originally Posted by oil pan 4
It's starting to sound like a typical electric vehicle. It does great in a real specific set of circumstances, then out side of that, not so much.
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That’s the age of specialization. Usain Bolt crushes the 100M, and that’s brilliant. You don’t have to be versatile, you only need to do something better than anyone else. That defines a whole new market.
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04-11-2021, 11:16 AM
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#19 (permalink)
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Helicopters have an issue above 200 mph where the retreating blade wont generate any lift and it generally turns into a corkscrew flight. The reason some experimental choppers have two blades counter rotating, but the drag bucket is phenomenal.
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04-11-2021, 09:33 PM
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#20 (permalink)
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It's all about Diesel
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Quote:
Originally Posted by Piotrsko
What ever happened to the GE turbofan with the external blades?
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That propfan? I wouldn't hold my breath for any to reach commercial viability, not only because of technical complexity but also because people tend to look at anything with an external propeller as outdated and unsafe.
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