Why battery-powered aircraft will never have significant range

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Saville

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For now, it appears that most/all of these new electric planes are being bought with government money (in whole or in part). When private flight school operators choose to spend their own money to buy them rather than buying IC engine acft, that will be a significant indicator that the technology is practical, at least in this narrow application.

IF and when.

Since the application is narrow (today), what's the benefit, aside from noise abatement?

So I do some pattern work with the battery. I still have to transition to ICE, and I've lost the instruction about carb heat, mixture control etc.

It would be interesting to know if the government subsidies made the cost of ownership so cheap that the flight school couldn't refuse the offer.
 

PagoBay

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Dan Johnson article on the Pipistrel Electro endurance flight:

EXECUTIVE SUMMARY:
Let’s be fair: Electric airplanes are relatively new and they will only get better. It is not reasonable to expect them to perform equally with fossil-fuel-powered aircraft that have been developed over many decades and with billions of dollars invested to help them achieve the high state-of-the-art they possess today.

Yet what this observes once again is that batteries are the weak link in the electric propulsion chain. Energy contained in batteries is a small fraction of that contained in a similar volume or weight of gasoline. That gap is narrowing but the pace seems glacial compared to forecasts of electric enthusiasts. Battery improvements of a few percentage points per year means decades before batteries match fossil fuel in energy per pound.

 

EzyBuildWing

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CopterPack is electric, so it needs the new light-weight Mazda-Wankel range-extender .....
Maybe ePipistrel needs it too for extending 20kW cruise-range, to "unlimited"?
.....maybe Martin Jet Pack re-launches too as electric with a range-exender.....
"Gravity" has a personal jet-pack consisting of 5 small jet-engines..... 1050 BHP Gravity claims.... If true, that's more than a Tesla.
Worth looking at.....maybe they'll do an IPO soon too......
 

Victor Bravo

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Electric flight training would work right now, with the batteries they have, if the training aircraft was a legitimate motorglider with a low sink rate. 10 minutes of high power climb, followed by 20 minutes of glide, then repeat once, then land with some battery reserve. A full hour of flying. Obviously this is limited to local, non-acro work.
 

Dan Thomas

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CopterPack is electric, so it needs the new light-weight Mazda-Wankel range-extender ..
So why not just use the ICE instead of the electric motor and all the batteries and fly lighter and cheaper?
"Gravity" has a personal jet-pack consisting of 5 small jet-engines..... 1050 BHP Gravity claims.... If true, that's more than a Tesla.
Worth looking at.....maybe they'll do an IPO soon too...
Of course they will. There are lots of gullible people with money to "invest."
 

Dan Thomas

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The fact still applies: If we convert wholesale to electric vehicles, we need much more electric power than we have now. One intelligent estimate, to meet the POTUS' requirement of being carbon neutral by 2030, says that we need to design, approve, build and put into service one or two nuclear powerplants every week, beginning back in May already, by 2030. Just imagine that happening. Ha.

And another fact still applies: The vast majority of people do not understand electricity. They have no knowledge of it other than it comes in 110 volts and 220 volts. They don't even know what a volt represents. Amperage and wattage mean nothing at all to them. They believe the nonsense about wind and solar replacing conventional sources. That nonsense is written by journalists and activists who don't understand amperage and wattage either. We have the blind leading the blind.
Further to this: it's already happening. And what percentage of California cars are electric?

Tesla asks owners to help 'relieve stress on grid' during heat wave in California, charge off-peak - Electrek
 

tspear

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@Vigilant1

Using your math, the 35% is reserve to save on the bottom end on the battery pack should be 17 minutes of flying, and the spec used in the video is for 10 minute reserve in some situations with one or two countries keeping flight time to 30 minutes for a 30 minute reserve.
A few interesting tidbits to note. The CEO stated that they expect the battery pack to double in endurance in three years, so not very long.
Second, posted previously in this thread and I read elsewhere, Pipistrel specifically picked a battery formulation which does not have a high power density. They picked one which meet the initial niche market requirements, lower in cost, reliable, stable and allowed the company to focus on many other issues. Basically they chose to de-risk the battery as much as possible and focus on all the other systems. This gives them plenty of room to grow on the battery front after they work out most of the other issues with the plane, and every new design has issues.

Lastly, remember, this is flight time not total time. So this is much moire useful than you probably think.

Tim
 

Saville

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@Vigilant1

The CEO stated that they expect the battery pack to double in endurance in three years, so not very long.
We have learned - through long, long experience - that those sorts of "expectations" are meaningless. So nowadays when I hear things like that the credibility of the speaker drops to zero.

Snake Oil Salesman.

IF and WHEN battery back endurance doubles - without sacrificing elsewhere - then let's see what that does for the viability, usability and marketability of electric airplanes.
 

Appowner

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Fact of the matter is the public's thirst for more, cheaper and cleaner energy will continue to drive this effort (among others) until such time it is deemed practical while actually costing more. Whether it really is practical or not. Is that time now? Maybe! But certainly within most of our lives.

One only needs to look at all the advances in the last 100 years to realize most anything is possible. It's just a matter of time and motivation. And if you aren't around to see it, well that's just the luck of the draw. Practical Electric flight is coming. Will it totally replace IC and/or Jet? Probably not. At least not anytime soon and not by itself. But there are certainly places where it can be a plus to whatever feel good cause one cares to advocate.

Actually I can see electric flight as being a savior of GA.
 

Saville

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Fact of the matter is the public's thirst for more, cheaper and cleaner energy will continue to drive this effort (among others)

What public? Which public? How much of the entire public wants this or even thinks about it? Whatever that fraction is, how many own and fly airplanes?

until such time it is deemed practical while actually costing more. Whether it really is practical or not. Is that time now? Maybe! But certainly within most of our lives.

Maybe. We've been hearing how it's imminent for decades now....

One only needs to look at all the advances in the last 100 years to realize most anything is possible.

Except that promoters have had around 60 of those 100 years to perfect this technology - and gotten some public and political support - and have yet to succeed.

It's just a matter of time and motivation.

I am not as confident as you that it will succeed.

Practical Electric flight is coming.

I will believe it when I see it. I'm not discouraging it...just waiting for real results.

Actually I can see electric flight as being a savior of GA.
To sum up:

Electric airplanes have had decades to flourish and so far have not. What has flourished is the hyperventilating about how it's just around the corner and it's going to be magnificent.

Maybe it will be magnificent...if it ever comes.

There has to be both technical success in both reliability and performance, and a market. None of these are guaranteed.

If it happens, great.

But until it does, 60 years of hype means I will remain skeptical.
 
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Vigilant1

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Actually I can see electric flight as being a savior of GA.
That could happen, eventually.
As I've mentioned elsewhere, I'm not in love with IC engines for their own sake and would be happy if affordable, reliable, powerful electric flight were here today. I don't agree, in principle, with the title of this thread because we can't know if "battery powered planes will "never have significant range." But I do know that overeager promisers and fans of electric power are hurting the cause.
 
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BBerson

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I thought you generally read this thread and paid attention. Pipestrel has multiple planes in production which match the C172 or C152 for training flights. And they are not motor gliders, but designed from the ground up as an electric plane.
You brought up C172 in post 1441. What model is it?
I have heard of four students in a C172. They observe from the rear seat. I don't know if they can log the rear seat time.
 

Appowner

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To sum up:

Electric airplanes have had decades to flourish and so far have not. What has flourished is the hyperventilating about how it's just around the corner and it's going to be magnificent.

Maybe it will be magnificent...if it ever comes.

There has to be both technical success in both reliability and performance, and a market. None of these are guaranteed.

If it happens, great.

But until it does, 60 years of hype means I will remain skeptical.
What public? Which public? How much of the entire public wants this or even thinks about it? Whatever that fraction is, how many own and fly airplanes?

The Sheeple for one. So if it doesn't have masses marching in the streets in support, do you discount it all together?

Maybe. We've been hearing how it's imminent for decades now....

Along with many other things like cancer, colonies in space, etc. Don't you find it somewhat selfish to expect such grand advances in such a short span as ones lifetime? After all even God needed six days to produce all he did. And on the flip side it took the bang or whatever billions of years to do likewise.

Except that promoters have had around 60 of those 100 years to perfect this technology - and gotten some public and political support - and have yet to succeed.

And again, why should it occur in your lifetime? And don't forget, I said motivation was also involved. Look at the space program. We went from basically zero to a man on the moon in less than 10 years. And in the 50 plus years since? Motivation has been lacking.

I am not as confident as you that it will succeed.

Confidence tempered with patience and an open mind.

I will believe it when I see it. I'm not discouraging it...just waiting for real results.

Rather than to ask why all the time, I prefer to ask why not?[/QUOTE]
 

Saville

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What public? Which public? How much of the entire public wants this or even thinks about it? Whatever that fraction is, how many own and fly airplanes?

The Sheeple for one. So if it doesn't have masses marching in the streets in support, do you discount it all together?

Sheeple huh? Ok so we know where you're coming from....

Nope not altogether. But when someone makes the blanket statement like:

"..the public wants it..."

I have to call them on that because the impression it leaves is that the entire mass of the public wants this.

And that's simply not true.

I prefer accurate statements not hyperbole.



Maybe. We've been hearing how it's imminent for decades now....

Along with many other things like cancer, colonies in space, etc. Don't you find it somewhat selfish to expect such grand advances in such a short span as ones lifetime? After all even God needed six days to produce all he did. And on the flip side it took the bang or whatever billions of years to do likewise.

I don't demand anything. I'm not the one saying it's right around the corner. It's not unreasonable to point out that in the last 60 years we've made great strides in almost every technological field.....

...but this one has failed even though it has monetary and political support.

It's not a *demand* to point that out.

And whether you like it or not...it may indicate that it's not a feasible technology, given the work on it during a time of public, political, monetary effort during the most incredible 60 years woth of advances in technology.


Except that promoters have had around 60 of those 100 years to perfect this technology - and gotten some public and political support - and have yet to succeed.

And again, why should it occur in your lifetime? And don't forget, I said motivation was also involved. Look at the space program. We went from basically zero to a man on the moon in less than 10 years. And in the 50 plus years since? Motivation has been lacking.

Show me where I demand it occur in my lifetime?

This is a strawman argument...i.e. you are trying to demolish a position I don't hold and never stated.


It wasn't I who brought up the 100 years of tech advancement..it was the person I was responding to.

Ok very well, let's see how well this topic has done in the last 60 of those 100 years.


I am not as confident as you that it will succeed.

Confidence tempered with patience and an open mind.

If you read my post very carefully you'll note this sentence near the end:

"If it happens, great."

...which clearly illustrates an open mind. i.e. the tech breakthroughs may occur and if they do great.


I will believe it when I see it. I'm not discouraging it...just waiting for real results.

You clearly saw this comment of mine...so that totally destroys your suggestion of a closed mind....

Doesn't it?

Why yes it does.

And this also clearly illustrates my position:

"But until it does, 60 years of hype means I will remain skeptical."

It's the hype that's the problem....not the concept.



Rather than to ask why all the time, I prefer to ask why not?

That's flowery rhetoric but not very logical. It's also irrelevant because I never said:

A) It will never happen or

B) That it would be bad if it did.
[/QUOTE]

Ask anything you like but do try to read carefully and grasp the point I'm making:

I'm not one who is saying that it will never happen - all kinds of things may work out - including failure.

But every time I see someone make a blanket statement like:

"...the public wants it..."

I'm going to call it out because it leaves an impression that borders on propaganda - whether it was intended to or not. And I fully realize the writer may not have intended to suggest the entire public - or even a large fraction - wants this. But this topic is fraught with so much emotionalism that statements like that need to be called out, and qualified.

So...I ask for clarification of what the writer meant.

Not sure why that bothers you so much.
 
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