Electric power for dummys......

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oldcrow

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With the cost of an electric motor being as high as a 2 stroke motor, I don't see where there would be much of a push to go electric. BUT if you use smaller EC motors like those in the Hobby scene could something like this work. (the drawing is kind of crude. i just threw it together) Using a gang of EC motors to turn the prop.EM GANG BOX.jpg
 

opcod

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If you are refering for a two stroke ... Price, then , this will equal a 100hp force easily. For a 2 stroke power, as around 30kw, it's more 4k. And what you should understand is with your gaz engine, make the count for how much is it after: gascolator, fuel selector, an fitting, flex tubing, seal, firewall, firehose, oil filter/mixer... You build a plane, buy cheap batterie for 5 min of run time and when you are really ready to do the real flight test, buy the next gen batt that will be about 6 time that the current power available is.
 

Aerowerx

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With the cost of an electric motor being as high as a 2 stroke motor, I don't see where there would be much of a push to go electric. BUT if you use smaller EC motors like those in the Hobby scene could something like this work. (the drawing is kind of crude. i just threw it together) Using a gang of EC motors to turn the prop.View attachment 91697
I like the idea. Worth looking into IMHO.
 

Vigilant1

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With the cost of an electric motor being as high as a 2 stroke motor, I don't see where there would be much of a push to go electric. BUT if you use smaller EC motors like those in the Hobby scene could something like this work. (the drawing is kind of crude. i just threw it together) Using a gang of EC motors to turn the prop.View attachment 91697
That could work, especially for existing airplane designs. The smaller motors will have more total weight than a larger motor with the same output, but the costs might still make it attractive.
But I wonder if ganging them to one prop makes best use of electric motors. A lot of smaller props (one per motor) might be lighter, more fault-tolerant (no single point of failure), more aerodynamically efficient (greater total disk area/lower disc loading), and more structurally efficient (no single concentrated load). Distributed propulsion which uses a lot of small motors in the wing's leading edge has been done, but the props could also be on the tail surfaces, nacelles or pods, etc.
 
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Dan Thomas

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If you are refering for a two stroke ... Price, then , this will equal a 100hp force easily. For a 2 stroke power, as around 30kw, it's more 4k. And what you should understand is with your gaz engine, make the count for how much is it after: gascolator, fuel selector, an fitting, flex tubing, seal, firewall, firehose, oil filter/mixer... You build a plane, buy cheap batterie for 5 min of run time and when you are really ready to do the real flight test, buy the next gen batt that will be about 6 time that the current power available is.
And for the electric: add the controller, power cables, battery boxes, batteries.....

In any project I've built it's the little details that end up costing so much more and driving the total price far beyond what I had anticipated. Every time. I have learned to double my best cost estimate and quadruple my time estimate.
 

12notes

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If you are refering for a two stroke ... Price, then , this will equal a 100hp force easily. For a 2 stroke power, as around 30kw, it's more 4k. And what you should understand is with your gaz engine, make the count for how much is it after: gascolator, fuel selector, an fitting, flex tubing, seal, firewall, firehose, oil filter/mixer... You build a plane, buy cheap batterie for 5 min of run time and when you are really ready to do the real flight test, buy the next gen batt that will be about 6 time that the current power available is.
Since batteries improve at 3-5% per year, and there has been no statistically significant changes to this rate over the last 50 years, this would only be true for a 37+ year build. This is an accurate schedule for some builders, but not the one they envisioned when they started.
 

Tiger Tim

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To coax in new adopters of electric, I think a turnkey system could be best. Check out this electric automotive crate motor:

upload_2020-1-5_5-37-32.jpeg

It even looks like the V8 it’s replacing! For aircraft use I was thinking of something a little smaller, maybe a VW replacement. Like an AeroVee but an Aero-E. The idea being that the motor(s), speed controllers, relays, and whatever else all come together in one lump. Preferably a lump that accepts existing throttle cables, engine mounts, and master switch wiring to allow quick(ish) conversions of already flying planes.

It’s just pie-in-the-sky dreaming stuff for now, but I think it’s an interesting avenue.
 

radfordc

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But I wonder if ganging them to one prop makes best use of electric motors. A lot of smaller props (one per motor) might be lighter, more fault-tolerant (no single point of failure), more aerodynamically efficient (greater total disk area/lower disc loading), and more structurally efficient (no single concentrated load). Distributed propulsion which uses a lot of small motors in the wing's leading edge has been done, but the props could also be on the tail surfaces, nacelles or pods, etc.
NASA agrees with you.

https://en.wikipedia.org/wiki/NASA_X-57_Maxwell

 

radfordc

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I didn't say it works....I said NASA thinks it's a good idea. But, what do they know?
 

proppastie

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blane.c

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The Lunacycle is an example of simplicity in an electric build. I am amazed at how clean this bike is. Check out the belt instead of a chain and the 3 speed rear end and the motor works harder the harder you pedal. Very cool. It would be nice to see that kind of thought in an electric aircraft.
 

Tiger Tim

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I'm waiting to see what they know. They're not infallible, as history has shown.
Looks to me that just like the early X-planes the X-57 is being built to explore something they have high hopes in but really don’t know about. I imagine some science types looking at the theoretical performance data and modelling while saying “That can’t be right... We better find out for sure.”
 
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