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Breathe
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All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Sep 17, 2021 1:25 pm

Congrats to Rolls-Royce and other partners involved.

https://www.cnbc.com/2021/09/16/all-ele ... light.html

Rolls-Royce’s first all-electric aircraft has completed its maiden flight, soaring across skies in the U.K. for around 15 minutes this week.

In a statement, the company said the aircraft’s trip on Wednesday marked “the beginning of an intense flight-testing phase” that would involve the collection of performance data on its electrical power and propulsion system.

According to Rolls-Royce, the airplane — dubbed the “Spirit of Innovation” — utilized a 400 kilowatt electric powertrain “with the most power-dense battery pack ever assembled for an aircraft.” Eventually, the firm wants the aircraft’s speed to exceed 300 miles per hour.

The Spirit of Innovation is the result of a program called ACCEL, or Accelerating the Electrification of Flight. Partners in the initiative include electric motor and controller specialist YASA and Electroflight, which Rolls-Royce described as an “aviation start-up.” YASA is a wholly-owned subsidiary of Mercedes-Benz.

In terms of funding, 50% has come from the Aerospace Technology Institute in partnership with the U.K. government’s Department for Business, Energy & Industrial Strategy and Innovate U.K.

In a statement issued alongside Rolls-Royce’s announcement, U.K. Business Secretary Kwasi Kwarteng said the aircraft’s flight was “a huge step forward in the global transition to cleaner forms of flight.”


Video of the plane on its maiden flight:

https://www.youtube.com/watch?v=Yqp9jhR1nnQ
 
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JetBuddy
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Sep 17, 2021 1:47 pm

That's a really good looking aircraft.

Congrats Rolls-Royce
 
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lightsaber
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Sep 17, 2021 2:29 pm

The aircraft has a range of 200 miles:
https://www.inceptivemind.com/rolls-roy ... c%20flight.

So this is a fun little aircraft. I like the looks, it seems to be stylized as a pre-WW2 racer. I'm trying to understand the bulges in the "engine compartment". As an addict of "Greg's Airplanes and Automobiles" on YouTube, I love finding out what every feature of an aircraft is for. I suspect there is more styling than purely required going on. Is there a view under the hood?
https://www.youtube.com/channel/UCynGrI ... gHJAIp9oSg

Congrats. Depending on the price, I could see a market for this plane. I really hope for a 9 passenger model with more range. Something to do Island hopping.

Lightsaber
 
WNwatcher
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Sep 17, 2021 9:38 pm

lightsaber wrote:
So this is a fun little aircraft. I like the looks, it seems to be stylized as a pre-WW2 racer. I'm trying to understand the bulges in the "engine compartment". As an addict of "Greg's Airplanes and Automobiles" on YouTube, I love finding out what every feature of an aircraft is for. I suspect there is more styling than purely required going on. Is there a view under the hood?

Lightsaber



I suspect that the bulges may be to allow airflow around for cooling off both batteries and powertrain. I suspect that the sleek racer design helps with keeping some forward CG in the air due to the weight of the batteries. Definitely one of the absolute coolest electric aircraft that I have seen so far!
 
Noshow
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 9:22 am

What would this be good for in real life? Some fast military drone?
 
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PM
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 9:51 am

JetBuddy wrote:
That's a really good looking aircraft.

Congrats Rolls-Royce

It's a modified NXT Racer (hence the registration). The design has been around for well over a decade.
 
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PM
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 9:52 am

Noshow wrote:
What would this be good for in real life? Some fast military drone?

It's really just a technology demonstrator.
 
Noshow
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 10:13 am

This one specifically yes. But using high density batteries for some fast electric vehicle must have some use? Many/all other companies go for payload or range or VTOL.
 
GDB
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 10:49 am

Noshow wrote:
What would this be good for in real life? Some fast military drone?


Same as any technology demonstrator, in this case for electric power, with a record in it’s sights, like many other demonstrators in aviation history.
With a view to develop it further, again the history of aviation history has numerous examples.
 
docmtl
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 3:15 pm

Inspired by 1931 Scheider's Trophy's winner, the Supermarine S6A.

Even the colour scheme is the same. Check it out:

https://www.airliners.net/photo/UK-Air- ... 6A/2599757

Beautiful sleek design :-)

docmtl
 
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JetBuddy
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 3:29 pm

PM wrote:
JetBuddy wrote:
That's a really good looking aircraft.

Congrats Rolls-Royce

It's a modified NXT Racer (hence the registration). The design has been around for well over a decade.


That's probably why it looks familiar.
 
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JannEejit
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Sat Sep 18, 2021 4:39 pm

In a more practical sense, Loganair in conjunction with Cranfield University are currently embroiled in a research project aimed at electrically powering a Britten-Norman Islander, which if successful would carry passengers on it's short inter-island hops around The Orkney Islands.
 
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HowardDGA
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Rolls Royce Electric Plane Reaches 387 MPH

Thu Nov 25, 2021 4:30 pm

 
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Spacepope
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Re: Rolls Royce Electric Plane Reaches 387 MPH

Thu Nov 25, 2021 4:53 pm

So, an electric Nemesis goes about as fast as a gas powered one. Neat!
 
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FLALEFTY
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Re: Rolls Royce Electric Plane Reaches 387 MPH

Thu Nov 25, 2021 5:03 pm

I think that electrification will soon be the way forward for new light and sport general aviation aircraft. Those market segments are less sensitive to range limitations and with the ever-increasing expense of Avgas, electric engines could eventually become cost-competitive.
 
Noshow
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 6:05 am

With batteries being so terribly heavy at very limited range I don't see many general aviation uses for electrical power.
Express cargo and maybe police traffic and observation drones might be the most likely application?
 
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Kiwirob
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Re: Rolls Royce Electric Plane Reaches 387 MPH

Fri Nov 26, 2021 6:18 am

Spacepope wrote:
So, an electric Nemesis goes about as fast as a gas powered one. Neat!


With about 10% of the range.
 
JonesNL
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 7:18 am

Noshow wrote:
With batteries being so terribly heavy at very limited range I don't see many general aviation uses for electrical power.
Express cargo and maybe police traffic and observation drones might be the most likely application?


Bottom end of the market will be forced to go electric or zero emission in the long term. AMS-LHR, CDG-LHR, Golden Triangle, etc will all be much cheaper by going electric. So, sub 400-500nm routes will be electric only. AMS started taxing planes heavily based on emissions. This will get worse and worse over time...

And electrical engines are cheaper than jet engines, but the batteries cost more and create extra weight. So, I think one on one a electric A220-300 should be price competitive with an electric variant...
 
2175301
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 7:27 am

JonesNL wrote:
Noshow wrote:
With batteries being so terribly heavy at very limited range I don't see many general aviation uses for electrical power.
Express cargo and maybe police traffic and observation drones might be the most likely application?


Bottom end of the market will be forced to go electric or zero emission in the long term. AMS-LHR, CDG-LHR, Golden Triangle, etc will all be much cheaper by going electric. So, sub 400-500nm routes will be electric only. AMS started taxing planes heavily based on emissions. This will get worse and worse over time...

And electrical engines are cheaper than jet engines, but the batteries cost more and create extra weight. So, I think one on one a electric A220-300 should be price competitive with an electric variant...


I don't see it as cheaper at all. The cost of the airplane stays about the same... and the passenger and cargo capacity goes way down due to the batteries taking up space and weight.

I see electric airplanes as more expensive per passenger or ton of cargo than hydrocarbon aircraft.
 
2175301
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Re: Rolls Royce Electric Plane Reaches 387 MPH

Fri Nov 26, 2021 7:27 am

Kiwirob wrote:
Spacepope wrote:
So, an electric Nemesis goes about as fast as a gas powered one. Neat!


With about 10% of the range.


and less than half the passenger or cargo capacity...
 
JonesNL
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 7:47 am

2175301 wrote:
JonesNL wrote:
Noshow wrote:
With batteries being so terribly heavy at very limited range I don't see many general aviation uses for electrical power.
Express cargo and maybe police traffic and observation drones might be the most likely application?


Bottom end of the market will be forced to go electric or zero emission in the long term. AMS-LHR, CDG-LHR, Golden Triangle, etc will all be much cheaper by going electric. So, sub 400-500nm routes will be electric only. AMS started taxing planes heavily based on emissions. This will get worse and worse over time...

And electrical engines are cheaper than jet engines, but the batteries cost more and create extra weight. So, I think one on one a electric A220-300 should be price competitive with an electric variant...


I don't see it as cheaper at all. The cost of the airplane stays about the same... and the passenger and cargo capacity goes way down due to the batteries taking up space and weight.

I see electric airplanes as more expensive per passenger or ton of cargo than hydrocarbon aircraft.


But cost of fuel and landing fees go down considerably. The main caveat is the trend of battery density improvements. If the same trend can be achieved as the last decade, we might see low range birds in development by end of 2030's. But it also depends on momentum, if hydrogen gains momentum and wins the infrastructure race electric flight will stay a niche. Same as with electric cars, hydrogen lost due to lack of momentum...
 
Noshow
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 8:47 am

I see liquid fuel as the perfect solution including for long term use. It will just be needed to be made green. Imagine on battery power every single landing will be overweight.
The current euphoria concerning electrical power for aviation is not warranted given the slow progress of current battery efficiency. Only with some breakthrough technology this might change one day.
 
JonesNL
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 10:47 am

Noshow wrote:
... given the slow progress of current battery efficiency. Only with some breakthrough technology this might change one day.


If anything the development is definitely not slow. Battery density has tripled in the last decade and only more money is flowing to research and production. Just follow the money.

Image

At the moment batteries are about 50 times worse then kerosene in energie density. If, and a big if, the density improves again by 3 times the equation changes to around 17 times worse. Another decade of tripling and we are at 5,5 worse.

There is no signal that investment and development in battery tech will slow down in the next decade. So, it is al dependent on keeping the trend going...
 
Noshow
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 11:03 am

That is exactly what I mean. We are still very far away from aviation usable battery weight and capacity. Range, speed and payload is what aviation is about.
Electric engines might be powered by electric energy generated on board from gas, liquids or nuclear power before we see batteries becoming capable enough?
 
JonesNL
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 11:28 am

Noshow wrote:
That is exactly what I mean. We are still very far away from aviation usable battery weight and capacity. Range, speed and payload is what aviation is about.
Electric engines might be powered by electric energy generated on board from gas, liquids or nuclear power before we see batteries becoming capable enough?


Well 20 years for having acceptable batteries is not that slow for a revolution in aviation propulsion, but that is down to perspective I guess...
 
Noshow
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 11:57 am

I fully support to look for improvements and carry on. I am just sceptic about the current hysterical rush to already develop airframes for some technology that is just not where it needs to be. A bit like this drone taxi hype. Who rents helicopters today instead of cabs? And this will be their future market?
It's okay to innovate and improve but let's stay realistic. Today a lot is just inflated hopes funded by risk capital looking for the biggest promise - realistic or not.
 
JonesNL
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 11:58 am

Noshow wrote:
I fully support to look for improvements and carry on. I am just sceptic about the current hysterical rush to already develop airframes for some technology that is just not where it needs to be. A bit like this drone taxi hype. Who rents helicopters today instead of cabs?
It's okay to innovate and improve but let's stay realistic. Today a lot is just inflated hopes funded by risk capital looking for the biggest promise - realistic or not.


On that I agree, for 90% of the developments its all hype and too soon. The tech is not there yet...
 
kalvado
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 12:20 pm

JonesNL wrote:
Noshow wrote:
... given the slow progress of current battery efficiency. Only with some breakthrough technology this might change one day.


If anything the development is definitely not slow. Battery density has tripled in the last decade and only more money is flowing to research and production. Just follow the money.

Image

At the moment batteries are about 50 times worse then kerosene in energie density. If, and a big if, the density improves again by 3 times the equation changes to around 17 times worse. Another decade of tripling and we are at 5,5 worse.

There is no signal that investment and development in battery tech will slow down in the next decade. So, it is al dependent on keeping the trend going...

Tripled if you disregard 2008 point.
If included, it is less than 2x over 12 years.
 
JonesNL
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 12:52 pm

kalvado wrote:
JonesNL wrote:
Noshow wrote:
... given the slow progress of current battery efficiency. Only with some breakthrough technology this might change one day.


If anything the development is definitely not slow. Battery density has tripled in the last decade and only more money is flowing to research and production. Just follow the money.

Image

At the moment batteries are about 50 times worse then kerosene in energie density. If, and a big if, the density improves again by 3 times the equation changes to around 17 times worse. Another decade of tripling and we are at 5,5 worse.

There is no signal that investment and development in battery tech will slow down in the next decade. So, it is al dependent on keeping the trend going...

Tripled if you disregard 2008 point.
If included, it is less than 2x over 12 years.


LCO was not really useful for transportation vehicles as it scored quite low on Safety and Specific power. I should have noted Mass produced chemistries for modes of transport...
 
Aliqiout
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 1:40 pm

Everytime electric airplanes come up on this site there is a flood of negative comments directed at something no one is suggesting.

No one is expecting or predicting an electric 737 replacement anytime soon, but electric powered GA planes and commercial service on short routes served by small prop planes today is clearly within reach.
 
kalvado
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 1:54 pm

Aliqiout wrote:
Everytime electric airplanes come up on this site there is a flood of negative comments directed at something no one is suggesting.

No one is expecting or predicting an electric 737 replacement anytime soon, but electric powered GA planes and commercial service on short routes served by small prop planes today is clearly within reach.

Question is how short route can it be.
Climb to FL300 takes 30 Wh/kg (kg of aircraft weight) as mgh. No drag or efficiency coefficients. 50 Wh/kg is likely realistically optimistic. and that is not per kg of battery, that is kg of aircraft weight.
Glide ratio for modern aircraft is about 20, so add as much for every 200 km of range
You have to be pretty optimistic to start doing further math.
 
JonesNL
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 2:16 pm

kalvado wrote:
Aliqiout wrote:
Everytime electric airplanes come up on this site there is a flood of negative comments directed at something no one is suggesting.

No one is expecting or predicting an electric 737 replacement anytime soon, but electric powered GA planes and commercial service on short routes served by small prop planes today is clearly within reach.

Question is how short route can it be.
Climb to FL300 takes 30 Wh/kg (kg of aircraft weight) as mgh. No drag or efficiency coefficients. 50 Wh/kg is likely realistically optimistic. and that is not per kg of battery, that is kg of aircraft weight.
Glide ratio for modern aircraft is about 20, so add as much for every 200 km of range
You have to be pretty optimistic to start doing further math.


If we assume (I know big assumption) 2 decades of tripling in battery density. We arrive at around 2700Wh/kg. Assuming a MTOW of 50ton you would need 925kg of batteries for climb to FL300 according to your 50Wh/kg number. Half the advancements in battery density and the weight is 1850kg. Sounds already quite viable, although it becomes less and less interesting for longer flights...
 
Noshow
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 2:25 pm

Let's assume we can harvest something like tidal energy or heat from inner earth to generate "green" liquid fuel like green kerosene, hydrogen or liquid hydrogen. Wouldn't this be way better, especially for aviation use? Even sunlight and air have been converted to fuel on some small experimental level.

Behind all the current green movement, that is honest by most people, I suspect a massive influence of industrial stake holders like nuclear power companies, mining companies and big financial investors. This is what keeps me from believing in this "fast and simple" push to immediate action campaign that gets promoted 24/7 with all this fear psychology. We are just not there. There is no use in spending all the tax money now - a lot is about industry wanting a lot of tax funding - only to find out in 15 years we should have waited just a little more.
Again I support improvements and to be open minded but we must remain realistic.

Coming back to the topic. Rolls-Royce should built the Ultrafan. This is the way to go for science, industry and the environment.
 
TheSonntag
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 2:46 pm

We will need electric and hydrogen propulsion in General Aviation. It is nothing less than a scandal that new GA planes still need leaded avgas.
 
sccutler
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 2:59 pm

Generally speaking, projects like this are for either (1) grant harvesting, or (2) virtue-signaling.

The relative merit of using public funds for stuff like this is a debate for another day, but we've about jumped the shark on the diversion of public resources (read, taxpayer funds, now and into the future ad infinitum by way of both future commitments and [mostly] evisceration of the value of money saved through engineered inflation), anyway. Suffice to say, opening the taxpayer funds tap will not materially affect the pace of battery development.

The virtue-signaling aspect is well enough understood, at this point, to not require further review.

But the bottom-line is that, as it stands today, there is no legitimate use for battery power in aviation, other than (1) extremely local training, and (2) unmanned surveillance / delivery use. And that last one is still troubling to those who choose to apply a little synapse time - "last-mile" delivery will virtually always be an order of magnitude more efficient through ground-based infrastructure (where, it should be noted, the economics of battery power work very well already, without the concomitant and inherent safety issues); and as for surveillance - who among us feels like we need greater intrusion from an inquisitive government?

There will be edge cases for electrically-powered commercial transport, but they will involve things like short-segment island hoppers or terrain-bypass. Odds are, they'll never be self-supporting, even then. If someone builds an electrically-powered A220 (or equivalent), it will be for the "feels," not the "dos."

And, when (really needs to be "if," but let's all be optimists, 'K?) battery technology reaches sufficient technical development to be safely used for viable commercial transport, the airframes and powerplants will be engineered to do it, and they will not be direct adaptations of dino-powered commercial transports. My $0.02 says it's going to be a hybrid arrangement, something that allows the use of electric propulsive devices (motors), the simplicity of which is most appealing, with a means of chemically-based energy storage and conversion to electrons. After all, batteries are nothing more than devices that use chemical state change for storage of energy, anyway. Fix that system (make it compact, safe and effective), and we're there.

Paging Dr. Brown - Dr. Emmett Brown - please send us some Mr. Fusion Energy Reactors!
 
kalvado
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Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 3:28 pm

JonesNL wrote:
kalvado wrote:
Aliqiout wrote:
Everytime electric airplanes come up on this site there is a flood of negative comments directed at something no one is suggesting.

No one is expecting or predicting an electric 737 replacement anytime soon, but electric powered GA planes and commercial service on short routes served by small prop planes today is clearly within reach.

Question is how short route can it be.
Climb to FL300 takes 30 Wh/kg (kg of aircraft weight) as mgh. No drag or efficiency coefficients. 50 Wh/kg is likely realistically optimistic. and that is not per kg of battery, that is kg of aircraft weight.
Glide ratio for modern aircraft is about 20, so add as much for every 200 km of range
You have to be pretty optimistic to start doing further math.


If we assume (I know big assumption) 2 decades of tripling in battery density. We arrive at around 2700Wh/kg. Assuming a MTOW of 50ton you would need 925kg of batteries for climb to FL300 according to your 50Wh/kg number. Half the advancements in battery density and the weight is 1850kg. Sounds already quite viable, although it becomes less and less interesting for longer flights...

You may safely assume that 9x will not happen.
While goals are ambitious, reality is more moderate. Here is a bit wider version of your chart:
Image
4x over 3 decades, while picking lowest hanging fruit.
 
JonesNL
Posts: 545
Joined: Tue Aug 06, 2019 2:40 pm

Re: All-electric aircraft from Rolls-Royce completes maiden flight in Britain

Fri Nov 26, 2021 4:00 pm

kalvado wrote:
JonesNL wrote:
kalvado wrote:
Question is how short route can it be.
Climb to FL300 takes 30 Wh/kg (kg of aircraft weight) as mgh. No drag or efficiency coefficients. 50 Wh/kg is likely realistically optimistic. and that is not per kg of battery, that is kg of aircraft weight.
Glide ratio for modern aircraft is about 20, so add as much for every 200 km of range
You have to be pretty optimistic to start doing further math.


If we assume (I know big assumption) 2 decades of tripling in battery density. We arrive at around 2700Wh/kg. Assuming a MTOW of 50ton you would need 925kg of batteries for climb to FL300 according to your 50Wh/kg number. Half the advancements in battery density and the weight is 1850kg. Sounds already quite viable, although it becomes less and less interesting for longer flights...

You may safely assume that 9x will not happen.
While goals are ambitious, reality is more moderate. Here is a bit wider version of your chart:
Image
4x over 3 decades, while picking lowest hanging fruit.


Yes and no. The real development and investment in battery tech for transportation started in 2010 and really took off the last 2 years. I think you would have a nice picture for context if you could overlay a chart with investment in R&D in Battery tech. Would be surprised if there is not correlation in the investment and the trend of energy density development. 4x in 3 decades would be rather disappointing and really low ROI on the R&D part...

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