How far are we from the perfect electric "homebuilt" ?

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12notes

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Batteries are heavy...and Lazair is a bit too heavy too to keep it electrified inside Part 103 rule.
Whoosh.

Everyone has been trying to tell you that batteries are too heavy for much more than an hour endurance in any small plane other than an extremely optimized motorglider before giving up because you believe untested claims and unrealistic extrapolations from RC planes over actual math, physics, and directly related aircraft experience. You've driven away most of the experienced, knowledgeable engineers on here, most have ignored you so they will never see your posts to correct your wild inaccuracies and inability to listen to facts. I haven't done that because this site has a high percentage of useful facts and information from informed experienced people, and that percentage is being lowered by the sheer volume of posts containing uninformed opinion masquerading as "information" that you're posting. Learn what constitutes proof, what the differences are between hypothesis and experiment, between claim and evidence, and maybe some actual physics before doing anything but asking questions here. And above all, be ready to accept answers from more experienced, knowledgeable people when they give you answers you don't like, instead of moving goalposts continuously and ignoring every fact that they give you to nitpick on something minor because you want your uninformed opinion to be right. This is not the first time electrically powered flight has been discussed or though of, a lot of people have the same wishes as you, but reality isn't based on wishes, it's based on what's actually possible.

And you still haven't provided any proof of the 3kW Lazair cruise claim, nor a 2 hour endurance flight, yet you spam even unrelated threads with this non-fact, and base nearly all your extrapolations on it. Reality just doesn't work that way.
 

Speedboat100

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Whoosh.

Everyone has been trying to tell you that batteries are too heavy for much more than an hour endurance in any small plane other than an extremely optimized motorglider before giving up because you believe untested claims and unrealistic extrapolations from RC planes over actual math, physics, and directly related aircraft experience. You've driven away most of the experienced, knowledgeable engineers on here, most have ignored you so they will never see your posts to correct your wild inaccuracies and inability to listen to facts. I haven't done that because this site has a high percentage of useful facts and information from informed experienced people, and that percentage is being lowered by the sheer volume of posts containing uninformed opinion masquerading as "information" that you're posting. Learn what constitutes proof, what the differences are between hypothesis and experiment, between claim and evidence, and maybe some actual physics before doing anything but asking questions here. And above all, be ready to accept answers from more experienced, knowledgeable people when they give you answers you don't like, instead of moving goalposts continuously and ignoring every fact that they give you to nitpick on something minor because you want your uninformed opinion to be right. This is not the first time electrically powered flight has been discussed or though of, a lot of people have the same wishes as you, but reality isn't based on wishes, it's based on what's actually possible.

And you still haven't provided any proof of the 3kW Lazair cruise claim, nor a 2 hour endurance flight, yet you spam even unrelated threads with this non-fact, and base nearly all your extrapolations on it. Reality just doesn't work that way.
1 video and Dale Kramers own words ( that included those claims ) were not enough for you ? How come I get the feeling anything I say is pretty much irrelevant to you ?

For your convinience..here is a real aviation engineer student's aeroplane video:
 
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stanislavz

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Nordic european country.
I am from other side of baltic pond. I have got some investemsts from eu, for inverter technolgy. But it have to go with some kind of university. You had to have some kind of inovation start-up ? And that is your goal ? it cant be just give me the money, i hant to build my first airplane..
 

Speedboat100

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I am from other side of baltic pond. I have got some investemsts from eu, for inverter technolgy. But it have to go with some kind of university. You had to have some kind of inovation start-up ? And that is your goal ? it cant be just give me the money, i hant to build my first airplane..
I developed earlier a woodcomposite and I got epoxies and veneers for free when I just asked. I think I may try the same method here.
 

stanislavz

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I developed earlier a woodcomposite and I got epoxies and veneers for free when I just asked. I think I may try the same method here.
Ok, bu that is your point ? To prove it doable ? to make better ? in 115 kg it is not high pricy as it may look.
 

12notes

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1 video and Dale Kramers own words ( that included those claims ) were not enough for you ? How come I get the feeling anything I say is pretty much irrelevant to you ?
No, you're again ignoring facts that do not agree with your previous conception. The 1 video contradicted your statement of a 2 hour flight, yet you persist. Dale Kramer's own words that he estimated 3kW, then later corrected it because it was proved wrong in testing. This was in the same link that YOU provided and failed to read all the way through.

I quoted back Dale Kramer's later words stating otherwise. From post #92 in this thread, quoting a post in YOUR link which you, for some unknown reason, still think is evidence when Dale Kramer later stated it was wrong.

"And later in that thread, the same person (Dale Kramer) posted:
"My duration estimate was based on my guess that 3 kw would keep the Lazair in the air. Unfortunately that was probably a low estimate based on Series I and II airplanes that were up to 100 lbs lighter than my Elite Electric Lazair""
 

Speedboat100

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Ok, bu that is your point ? To prove it doable ? to make better ? in 115 kg it is not high pricy as it may look.
I just want to make a aeroplane that is able to take off from snow, water and ground with minimal hp/kw as possible. I also want to see how small amount of expences if anything has to be spent to it. Usually I end up bying tools that cost more than the product at the end.
 

Speedboat100

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No, you're again ignoring facts that do not agree with your previous conception. The 1 video contradicted your statement of a 2 hour flight, yet you persist. Dale Kramer's own words that he estimated 3kW, then later corrected it because it was proved wrong in testing. This was in the same link that YOU provided and failed to read all the way through.

I quoted back Dale Kramer's later words stating otherwise. From post #92 in this thread, quoting a post in YOUR link which you, for some unknown reason, still think is evidence when Dale Kramer later stated it was wrong.

"And later in that thread, the same person (Dale Kramer) posted:
"My duration estimate was based on my guess that 3 kw would keep the Lazair in the air. Unfortunately that was probably a low estimate based on Series I and II airplanes that were up to 100 lbs lighter than my Elite Electric Lazair""
Yes he claims his series I and II used only 3 KW. I get it.
 

stanislavz

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I just want to make a aeroplane that is able to take off from snow, water and ground with minimal hp/kw as possible. I also want to see how small amount of expences if anything has to be spent to it. Usually I end up bying tools that cost more than the product at the end.
Then just buy an used motor glider. And for electronics power unit - now there are plenty of possibilities - from stacking up rc toys, to used gear from hybrid/ev cars.

From my point - i would just buy this one (it is called straton d7) :



It is ugly, as a glider, have only 16 18 glide ratio- , but it fill in far 103 with trabant motor direct driving propller weighting 45 kg with prop + fuel. So you can really stuc here 40-35 kg of batteries. And it will give you better resulult, than on lazair.
 

Aerowerx

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1 video and Dale Kramers own words ( that included those claims ) were not enough for you ? How come I get the feeling anything I say is pretty much irrelevant to you ?

For your convinience..here is a real aviation engineer student's aeroplane video:
Why did you post this? This is a perfect example of 12notes' statement!

It has nothing to do with electric flight. You are just proving that 12notes, and every one else, is correct!
 

litespeed

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I am with the crowd on this, I have tried to contribute and be scientific about the whole electric flight issue.

But it is like banging my head against a wall, sometimes, it is better to stop.

There is no magic than can be involved nor will what some believe overcome physics.
 

Speedboat100

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No, he estimated the 3 kw. No actual testing on the earlier series. It was little more than a guess, which can come too close to wishful thinking.
But it can also be 2 KW...see the wingloading on the Lazair...when tanks are nearly empty.
2 metric ton Solar Impulse II used only 7 KW at night to soar.
 
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Speedboat100

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I am with the crowd on this, I have tried to contribute and be scientific about the whole electric flight issue.

But it is like banging my head against a wall, sometimes, it is better to stop.

There is no magic than can be involved nor will what some believe overcome physics.

You have no need to bang your head here. I am trying to make a 50 kg aeroplane with high lift devices and sorta stretch the envelope in electric flight..in a way that has never been done before. Be patient.
 

Speedboat100

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Why did you post this? This is a perfect example of 12notes' statement!

It has nothing to do with electric flight. You are just proving that 12notes, and every one else, is correct!
I posted it to show how a real aviation engineer student solves the issues in aircraft design. 12 notes referred to them.
 
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Speedboat100

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Then just buy an used motor glider. And for electronics power unit - now there are plenty of possibilities - from stacking up rc toys, to used gear from hybrid/ev cars.

From my point - i would just buy this one (it is called straton d7) :



It is ugly, as a glider, have only 16 18 glide ratio- , but it fill in far 103 with trabant motor direct driving propller weighting 45 kg with prop + fuel. So you can really stuc here 40-35 kg of batteries. And it will give you better resulult, than on lazair.
How about this on motors (light electric): https://www.limis.lt/paieska/perziura/-/exhibit/preview/80000000307554?s_id=VwQUCvP4dUGWa3I4&s_ind=33

Do you know the weight of it ?
 
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