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The electric airplane is another myth. There is no known battery technology, or one on the horizon, that can provide a large enough power/weight to make them practical.

The investors are getting bilked.




> There is no known battery technology, or one on the horizon, that can provide a large enough power/weight to make them practical.

Small aircraft are already there. I'm looking into starting my pilots license this year, the local flight school recently acquired an Elektra Trainer [1], that apparently has 2.5 hours worth of flight time [2].

Big transoceanic widebodies obviously will be fossil fuel based for a long time to come, but I think a lot of the GA market and bush pilot/island hoppers can and will be done by electric planes sooner than later - alone because the noise and lead emissions are all but gone, and I think that in a few years, when experiences on failure modes are a bit richer, electric planes will also be cheaper to maintain - similar to cars, there are less parts involved in the first place that can break down.

[1] https://de.wikipedia.org/wiki/Elektra_Trainer

[2] https://www.br.de/nachrichten/bayern/elektrisch-fliegen-in-l...


It appears to be an ultra-light.


It is, because it's easier to get started with certification and experience in ultralights than in full-size planes. It won't be long until we see bush capable Cessnas, I think.


They use electric seaplanes at Harbour Air for regional flights across the Georgia Strait between Vancouver, Seattle, and Victoria. Electric makes a lot of sense for short-range flights.


No, the eBeaver has never flown a commercial flight. Harbour Air is aiming for certification in 2026. Additionally, it only holds four passengers and is more a proof of concept than anything else. It is a cool effort but battery technology needs to come a long way first.


Firstly: I'm a fan of Harbour Air's work and their electrification. Have flown that airline.

Retrofitting electrical flight to a 1950s airframe will be, in the long run, not a great use of the technology.

Those planes were designed around having a single heavy powerplant up front driving the propeller, and fuel largely distributed along the center of gravity (in the wings) so as not to adversely alter flight characteristics over the trip. The electrified Beaver stores its batteries in the fuselage; of course there is no change in mass/CG over the flight with electric, but all that fuel tank space in the wings is going to waste. The fact that these are floatplanes make charging/battery replacement tasks at the dock challenging and restrict options.

A clean sheet design, with multiple distributed smaller motors and more options for battery placement, will be a significant improvement.

https://harbourair.com/going-electric/?tab=Specification


Storing the weight in the wings significantly reduces the stress in the wings over storing it in the fuselage.

Makes me wonder about their design tradeoffs.


Beta Technologies is already shuttling cargo between bases/depots for the US military with their eVTOL aircraft.

Demonstrated range of over 300 nautical miles. Significantly higher reliability than helicopters previously used for the same task, and much cheaper.


Silly idea, but if the power is needed for takeoff then the aircraft could be plugged in with a cable up until it reaches cruising altitude.

It sounds ridiculous but I’ve been in aircraft that take off while attached to a cable thousands of feet in length — a winch launched glider!


The risk assessments are a teeny bit different.

Edit: although maybe there's a good idea: catapult or winch launch for electric aircraft would massively reduce the power and energy storage requirements to be carried onboard.


Look at all the effort that goes into launching an airplane with a catapult on an aircraft carrier.

There are other issues - like you cannot abort a catapult in progress.


Being constrained to a ship makes things harder though. If it was simply very long (runway length), I reckon an abort would be fine. There are probably a lot of different ways to do it.

But yeah, much harder than a regular runway. Probably not economical.


Considering how thick fast charging cables for cars are, I don't think it will fly, literally. We could make the cables thinner with high enough voltage I guess. But then we would actually need two wires with proper separation, because unlike with trains, you obviously can't use the ground for the return path. Loose high voltage wires may be a safety problem too.

By comparison glider launch wires are quite thin and light.


> The electric airplane is another myth.

Strong disagree. Short range eVTOL craft will blow open the market for all kinds of use cases.


I've heard that story for 40 years. Invest in it if you like. I'll pass.


eVOTL only started making sense when we got the battery power density and computer flight control systems available now.


They're great for trainers. Short hops with immediate control, low maintenance and operating cost, and you can save the magneto/ignition/etc workload for a different lesson series.


I can see that. Although managing the engine is a major part of learning to fly.


So, make electric airplanes the initial license, reduce the amount of hours to get it, and have an entire course on monomotors before pilots can deal with combustion airplanes.


Exactly. Flying the airplane is the first 90% of flying, managing the engine is the other 90%. So it helps to set one aside while you work on the other.


I feel there is an unaddressed market for a hybrid gas/electric or diesel/electric powerplant.

Size the battery for takeoff/climbing/go-around/diversion use-cases. Size the fossil-fuel engine for cruising power, which should improve efficiency. During takeoff and climbing power, the two motors work together. During cruise and descent, the electric motor regenerates the battery. I imagine that for general aviation, you would maintain one propshaft and not even bother with a clutch pack, since the gas engine is needed in all phases of flight, and freewheeling an electric motor is simple. Perhaps have the fossil-fuel engine keyed to the shaft with a shearing pin, so that if the engine seizes, the electric motor still turns the prop.

This has the advantage that you now have two independent motors, which could eventually help with ETOPS rating, but would initially improve safety/reliability for general aviation.

Yes, you are still fossil-fuel dependent, but you burn much less of it, first by offsetting some takeoff energy to the electrical grid, and secondly by reducing reserve power in the fossil fuel engine to improve efficiency.


Really? The Beta Alia CX300 just completed a coast to coast journey (Vermont - Santa Monica). Range of about 338 miles using 200kwh of completely unremarkable ~150wh/kg batteries. With 500wh/kg batteries being announced from multiple manufacturers now, that range should improve pretty quickly.

> There is no known battery technology, or one on the horizon,

The planes and batteries are getting there.


You're assuming these investors actually believe it, and not that they can sell it to a greater fool.

VC will invest in snake oil if they think they'll get out at a profit.


The plane, of course, flies anyway becuase planes don't care what humans think is impossible

/j


I didn't say it was impossible. I said there was no known technology that would make it work.


> to make them practical.

..practical to replace commercial airliners, sure. There have been plenty of slow electric planes.

In the future, net-zero air travel can only be done by producing jet fuel in a carbon neutral way.


I thought they might make sense for trainer aircraft that flight schools would use.





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