Electric Airplane Developments

[Less Hair]

Batteries are rapidly getting smaller and the capacity increasing.

This has been the hope for the last hundred years.

[Jhieminga]

There was a fleet of thirty electrically driven taxis in Amsterdam around 1910 (out of a total of 240 registered cars). Back then the expectation was that electrically powered vehicles were the future. Look how far we've come since then....

[Less Hair]

The first Porsche: Electric but two tonnes of weight.
https://newsroom.porsche.com/en/prod...ory-18563.html

[Jan Olieslagers]

Batteries are rapidly getting smaller and the capacity increasing.

Which dramatically increases the energy density and with it the danger.

[First_Principal]

Jan Olieslagers Energy density does not necessarily = danger...

However, as most clearly realise, with conventional electric transportation it's the energy density of the supply that's the limiting factor at present.

What brings things into perspective is a comparison of the best portable electric source (let's say a Lithium-ion battery) against a unit of petroleum. If we use Joules per kilogram we find that 1kg of petrol has ~44MJ/kg, a Li-ion battery has ~0.6MJ/kg, give or take. Thus conventional fuel typically contains around 70 times the energy per kilo than electric.

This is offset to some extent by the relative efficiency of converting this energy into power that will propel your 'plane. It's a complex field, but for the purposes of a simple comparison let's assign an efficiency of 90% to electric, and 30% to a combustion motor.

However, while the electric system has much greater efficiency, from a practical perspective it clearly remains overwhelmed by the vastly superior energy density of petroleum.

So, there have been significant advances in (electric) energy storage over the past 20-30 years but, unless there is a 'eureka' moment, I feel it will be quite a long time before it becomes fully viable and comparable to 'conventional' fuel-powered aircraft.

FP.

[Fl1ingfrog]

Yes Jan, but then petroleum products burn and fuel tanks explode. Fatal Carbon Monoxide poisoning is also all too common. First Principal outlines neatly where we are.

The development of electric vehicles is dependant on more than only the battery. As for how rapid things will develop, nothing before has stimulated the need more than the environmental concerns of today.

[The Ancient Geek]

Without major advances in battery technology which is unlikely to happen soon the energy/weight factor makes practical endurance/range aircraft impractical.
Hydrogen is a lot more promising but will need a very expensive refueling infrastructure. There are also questions about carbon neutral production of hydrogen, this would need a lot of green electricity.
There is a lot of work going on to solve the problems, my best guess is that light aircraft will use electric motors powered by hydrogen fuel cells.
All of this is unlikely to happen very quickly for light aircraft which have a service life of 40+ years so there will be no rush to replace these expensive assets with new technology. Avgas will be with us for decades more.

[Pilot DAR]

Avgas will be with us for decades more.

Is true. Though the economy of Avgas may leave us. As the cost of fuel makes flying prohibitive for many pilots, they fly less, which results in reduced pilot currency. In an airline environment, simulators can make up a lot of this, but for GA, we're going to need a modest cost means to keep pilots, particular less experienced pilots, in the air. Electric planes will not fly far or for long, but if they keep GA pilots current, that's something....

[Fl1ingfrog]

Having passed my three score years and ten little to nothing of the past feels that far away. I bought my first mobile in 1992. I say bought but you rarely did because they cost then £2000 or $3000 dollars so you rented on a lengthy contract. The phone was the size of a ladies handbag. the battery would hardly last more than a couple of hours of use so I had four. Each battery was the size of a machine gun cartridge. The telephone did one thing: make and receive telephone calls. Today, my mobile slips into my shirt breast pocket and has the facility of a powerful computer. The battery is tiny and will last all day if not two. There is very little it can't do including being a high definition camera and act as a comprehensive GPS; both for aviation and with road moving charts/maps for navigation. For road use the software can be free with apps such as Waze. All this is for a few hundred pounds.

So, for me, 20 - 30 years ahead is no time at all, its if it was tomorrow. Avgas is already struggling to survive as petrol is required less and and in some parts of the world impossible to buy. It may not be the case that Avgas is only expensive then, in the foreseeable future, but it could prove difficult to obtain irrespective of price. Mineral oils already are only available because of the total loss demand of the food processing industry. Oil producers don't see their future in petroleum products. They would stop making avgas and mineral oils tomorrow if they could.

[Jan Olieslagers]

Avgas will be with us for decades more.

I'm not so sure there. I'll readily agree that "fossil fuels" in general will be available for quite a while - longer than my lifetime, sure enough. But fossil fuels ARE on the way out, and AvGas being a rather rare variety it will be among the first to go. MoGas will stay a bit longer, especially if alcohol-doped; diesel/kerosene much longer, because a lot of commercial transport depends on it.

Energy density does not necessarily = danger

Oh yes, it does. The question is: to what degree is the danger known and addressed and controlled? Surely fossil liquid fuels have their own dangers, and accidents can and do happen, but the risks are known and there are procedures to deal with issues. With batteries, much of that knowledge still needs to be built up. For one example, fire brigades are recently learning that a car with a burning battery can only be extinguished by immersing it in a tub full of water, and such tubs are now being constructed here and there. How to deal with the same condition in your SEE is yet to be determined.

[Maoraigh1]

"Avgas will be with us for decades more."
Who are "us"? There is talk of big oil/gas development by Eastern nation organisations in the Kurile Islands region. Not everyone is going "carbon neutral".

[Fl1ingfrog]

Published in Avweb today;"Diamond Aircraft says the electrified version of its DA40 single will have up to a 90-minute endurance and charge time of 20 minutes. The company announced on Wednesday it has chosen Safran’s ENGINeUS electric motor to power the eDA40. “With Safran we are having an expert partner for electric propulsion systems aboard,” said Liqun (Frank) Zhang, CEO, Diamond Aircraft Industries Austria. “The smart motor’s state-of-the-art technology including smart features paired with a well-advanced certification process is the logical choice for our eDA40. We are looking forward to the first flights scheduled for end 2022.”

Diamond announced the program last October. The aircraft is aimed at the training market and Diamond is predicting a 40 percent decrease in operating costs for flight schools. The 90-minute endurance likely won’t be achieved immediately but will be possible as battery technology evolves. Diamond is predicting certification for the motor by mid-2023 and basic EASA certification of the aircraft in late 2023 or early 2024."

So perhaps we won't be waiting as long some doubters believe

[Less Hair]

There are totally new aspects to think about, battery health one of the most prominent. Like charging software, charging power used and peak power use, battery temperature, environmental temperatures in cruise flight, battery aging. It will take a while until this is good enough for Joe public.

[Jan Olieslagers]

Originally Posted by Less Hair

There are totally new aspects to think about, battery health one of the most prominent. Like charging software, charging power used and peak power use, battery temperature, environmental temperatures in cruise flight, battery aging. It will take a while until this is good enough for Joe public.

Precisely. On the long term, fossil fuels are dead, and batteries are today the only realistic alternative. Still, they are far from being "market-ripe".

So perhaps we won't be waiting as long some doubters believe

To me it seems rather that we will wait longer than some hopers believe. Especially in the very conservative environment of aviation in general, and private aviation in particular.

[Fl1ingfrog]

To me it seems rather that we will wait longer than some hopers believe. Especially in the very conservative environment of aviation in general, and private aviation in particular.

This company thinks differently:

Massachusetts-based commuter airline Cape Air has signed a letter of intent (LOI) with Eviation for the purchase of 75 all-electric Alice aircraft. The terms of the agreement have not been made public. As previously reported by AVweb, Eviation announced in June 2019 that Cape Air would be its first commercial customer for the aircraft, which is still in development.

“Truly sustainable aviation not only reduces the impact of air travel on the environment but also makes business sense,” said Jessica Pruss, Eviation vice president of sales. “We are proud to support Cape Air, a recognized leader in regional air travel, to chart a new path in delivering innovative solutions that benefit airline operators, passengers, communities and society.”

Cape Air currently flies more than 400 flights a day to locations in the Northeast, Midwest, Montana and the Caribbean. According to Eviation, the Alice will have a top cruise speed of 250 knots, maximum payload of 2,500 pounds and single-charge range of 440 NM. The aircraft will seat nine passengers and two crew members and is powered by the magniX magni650 electric propulsion unit. Eviation noted last February amidst a leadership change that it was expecting to fly the Alice for the first time “in the upcoming weeks.”

[Jan Olieslagers]

This company thinks differently:

Excuse me for being unimpressed. A letter of Intent is not an order, not by a long way. How could it? This Alice thing has not yet flown (except as a scale model), to not even mention certification. Baked air has a fine scent, admittedly, still you shouldn't be led by the nose.

[HOVIS]

https://insideevs.com/news/583324/pa...ter-two-fires/
No idea what has caused this but perhaps these quick change aircraft batteries should also be ejectable. 😁

[MungoP]

Today's Telegraph has a piece on the Sherwood E Kub having flown for a thirty-minute flight over Norfolk.. .. smart looking aircraft, except for the upside-down depiction of the Union Jack.:</

[Pilot DAR]

Sherwood E Kub having flown for a thirty-minute flight over Norfolk

Excellent. I believe that the pilot contributes here from time to time, I hope he'll tell us a little about this project when the time is correct for that...

[nomorecatering]

Fossil fuels are not dead. The post globalisation world will see to that. By the time legacy fossil fuels are getting difficult to extract there will be a range of synthetic liquid fuels on the market. Crude oil can be made from algae, or from thin air. Liquid hydrocarbon fuels and internal combustion engines will be around for a very long time.