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Old 9th October 2023, 05:38 PM   #1
Gord_in_Toronto
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Electric Planes

I seem to remember this being discussed in another hread but it probably deserves one of its own anyway.

It looks as if the reality of planes powered by electric motors (and thus mostly batteries) is getting closer. Here is one example of such progress:

Future of Aviation? NASA and U.S. Air Force Testing Joby’s Electric Vertical Takeoff and Landing (eVTOL) Aircraft

You can follow along the progress here:
ADVANCED AIR MOBILITY REALITY INDEX

IMHO there's probably another leap in battery technology required before EPs become mainstream but promoters are promoting really hard.
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Old 10th October 2023, 02:08 AM   #2
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Well, electrically powered aircraft are already a reality, in the form of drones. Multirotor drone lay-outs are quite scalable, control software is already well developed, so we shall no doubt soon see them as short range VTOL craft, capable of carrying passengers and smaller loads.

Otherwise, for both rotor and fixed wing configurations, range and weight/load ratio is a big hurdle. So I agree that energy storage (I avoid the term 'battery' on purpose) is a main issue.

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Old 10th October 2023, 03:55 AM   #3
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Well, we already have electric training aircraft here in NZ, the Pipistrel Alpha Electro run by ElectricAIr Flight School

https://www.electricair.nz/

They are very cheap to run. Typical price for flying lessons in, say, a Piper Tomahawk, a Piper Cherokee or a Cessna 172 runs at about NZ$250 to $275 per hr. ElectricAir are charging about 190 per hr

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I AGREE
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Old 10th October 2023, 06:56 AM   #4
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Originally Posted by MRC_Hans View Post
Well, electrically powered aircraft are already a reality, in the form of drones. Multirotor drone lay-outs are quite scalable, control software is already well developed, so we shall no doubt soon see them as short range VTOL craft, capable of carrying passengers and smaller loads.
Carrying passengers is not so easy. The larger you scale a multirotor, the harder you stress the rotor components, meaning that reliability becomes more difficult. Yeah, we are able to scale them to large sizes, but what happens if a rotor fails? For a small drone, that's not such a big deal. Even for larger drones, that's still OK as long as you don't hit anyone on the ground. You can tolerate failure rates that no passenger aircraft could ever last with. But you can't tolerate failure rates with passengers that you could with small cargo. We aren't close to having an established safety record for copter drones capable of carrying passengers that would make this commercially feasible. It's not an impossible task, but it's a really, really big one, and it's probably going to take a long time (as in decade+) to solve.

Quote:
Otherwise, for both rotor and fixed wing configurations, range and weight/load ratio is a big hurdle. So I agree that energy storage (I avoid the term 'battery' on purpose) is a main issue.
It's either a battery or a fuel cell. Nothing else is going to give you electricity directly, and a hybrid engine plane isn't an electric plane.
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Old 10th October 2023, 07:11 AM   #5
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One thing I realized, looking at drone use in Ukraine, is that larger payloads means larger batteries, and unlike fuel tanks batteries don't get lighter over the duration of the flight. It seems that above a certain payload size, the dead weight of depleted batteries tends to offset the benefit of an electric drone, and you're better off going back to ICE.

Also, VTOL is ridiculously energy-expensive, compared to other forms of powered flight. It's a niche application, for when you are putting a very high premium on being able to land and take off from anywhere, without a runway. Military applications, of course, where winning is more important than mere fuel efficiency. Ostentatious executives, who have money to burn. Etc.
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Old 10th October 2023, 09:58 AM   #6
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As a follow-up to my notes above about human safety. For planes (electric or not), you can survive an engine failure by gliding to the ground. Helicopters can actually do something similar with autorotation. Not as simple a maneuver, but helicopter pilots train for it. But it requires being able to adjust the pitch of the blades.

Quad copters and the like have fixed pitch blades. They adjust lift by changing rotation speed of the blades. But that also means that you cannot do autorotation. And they can't glide either. Basically, if you have an engine failure in a quad copter style design, you're going to crash. With passengers, that means engine failures are not really survivable events. There's no way in hell that gets widespread adoption.

And if you want to add blade pitch capability, then there's really little point in using a quad copter style design rather than a traditional helicopter.
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Old 10th October 2023, 11:30 AM   #7
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This looks interesting. https://www.eviation.com/

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Old 10th October 2023, 12:03 PM   #8
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Originally Posted by Ranb View Post
This looks interesting. https://www.eviation.com/

Ranb
Why does it have an air intake for its motors? Does it really need that much cooling?
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Old 10th October 2023, 12:26 PM   #9
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Originally Posted by Ranb View Post
This looks interesting. https://www.eviation.com/

Ranb

Which brings up a point.

The vast, and I mean VAST majority of airliner flights are short range commuter flights with small passenger numbers. They have the greatest impact on the environment as regards emissions, so much so that some countries are banning them. But electric aircraft could fill replace many conventional fuel-powered aircraft on short-haul flights and there are technical reasons why that could be a good thing.

One of the greatest impacts on the life of an aircraft is not, as you might expect, the number of flight hours, but the number of "pressurization cycles". Each cycle involves a takeoff, a pressurization sequence and a landing. Aircraft on short-haul services undergo a lot of pressurization cycles, but the reason they need to do this is because the engines are more efficient at higher altitudes, so they need to fly higher to be at their most economical.

However, electric aircraft have no such constraint. There are no efficiency gains to be had by flying at 20,000 ft instead of 2,000 feet so - in fact, it is probably more efficient for electric aircraft to fly lower. Consequently, there is no need for a pressurization system. Short haul electric aircraft could fly much lower, meaning no need to waste battery power climbing to high altitudes. I can easily see a small commuter airliner like the one shown in RanB's link flying a 500km flight from one airport to another at 1,000 ft AGL instead of the usual 20,000 ft by something like a Citation or a Gulfstream.
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Old 10th October 2023, 12:34 PM   #10
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Originally Posted by smartcooky View Post
Aircraft on short-haul services undergo a lot of pressurization cycles, but the reason they need to do this is because the engines are more efficient at higher altitudes, so they need to fly higher to be at their most economical.

However, electric aircraft have no such constraint. There are no efficiency gains to be had by flying at 20,000 ft instead of 2,000 feet
That's not quite true. The engine efficiency might not change, but drag efficiency does. Drag at 20,000 feet is a lot lower than at 2,000 feet.

Quote:
in fact, it is probably more efficient for electric aircraft to fly lower.
Only if you also go slower. Which has significant downsides in terms of what people want.

The overall balance might still allow for economic short range electric flights, but I don't think the case is as obvious as you suggest.
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Old 10th October 2023, 12:41 PM   #11
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Originally Posted by Ziggurat View Post
Why does it have an air intake for its motors? Does it really need that much cooling?
Yes. They are the air intakes of the motors' Thermal Management Systems (TMS). Electric and Hybrid-Electric Aircraft propulsion systems rely on high-power electrical equipment, electric motors, voltage/current converters, power electronics and batteries. These items dissipate heat at a much higher rate than conventional propulsion aircraft systems.

The Eviation Alice uses a though-flow ventilation system for the the TMS - you can see the exit holes at the rear of the engine nacelles.
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Old 10th October 2023, 01:03 PM   #12
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Originally Posted by Ziggurat View Post
That's not quite true. The engine efficiency might not change, but drag efficiency does. Drag at 20,000 feet is a lot lower than at 2,000 feet.
True, but it is a much smaller part of the equation. Over 80% of the efficiency gains from flying at altitude come from greater engine efficiency

Flying at altitude might give you better drag efficiency, but you have to get there first. Most of those gains are eaten up by the losses incurred in using battery power. It costs more power to climb than it does to fly level, and in the case I am making, short haul, very little of the flight time is spent at high altitude.

Originally Posted by Ziggurat View Post
Only if you also go slower. Which has significant downsides in terms of what people want.
The Eviation Alice has a cruising speed of 481 km/hr. The type of aircraft it would be competing against are

ATR72 - 510 km/h
Cessna Skycourier - 389 km/h
Piper PA31 Navajo - 383 km/h

That's not a lot of difference
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Old 10th October 2023, 01:11 PM   #13
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Originally Posted by Ranb View Post
This looks interesting. https://www.eviation.com/

Ranb
Originally Posted by Ziggurat View Post
Why does it have an air intake for its motors? Does it really need that much cooling?
Originally Posted by smartcooky View Post
Yes. They are the air intakes of the motors' Thermal Management Systems (TMS). Electric and Hybrid-Electric Aircraft propulsion systems rely on high-power electrical equipment, electric motors, voltage/current converters, power electronics and batteries. These items dissipate heat at a much higher rate than conventional propulsion aircraft systems.

The Eviation Alice uses a though-flow ventilation system for the the TMS - you can see the exit holes at the rear of the engine nacelles.
Huh. I assumed it was just the usual turboprop intake. Use electrical power to suck in the air, compress it, then use the compression to drive the propeller.
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Old 10th October 2023, 01:17 PM   #14
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Originally Posted by theprestige View Post
Huh. I assumed it was just the usual turboprop intake. Use electrical power to suck in the air, compress it, then use the compression to drive the propeller.
No, the motors are not turboprops, they are electric motors.

(fast forward to 3:16 if the link doesn't take you there automatically)

ETA: https://youtu.be/ZCTQiuHAFSQ?t=196
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Old 10th October 2023, 01:29 PM   #15
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Originally Posted by smartcooky View Post
No, the motors are not turboprops, they are electric motors.

(fast forward to 3:16 if the link doesn't take you there automatically)

ETA: https://youtu.be/ZCTQiuHAFSQ?t=196
Huh. I assumed that the "turbo" in "turboprop" came from adding energy by compressing the air and then using that energy to drive something. And that electricity rather than combustible fuel could be used to add energy in the compression step. I.e., one could use an electric motor to drive a turboprop.
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Old 10th October 2023, 01:30 PM   #16
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Originally Posted by Ziggurat View Post
Carrying passengers is not so easy. The larger you scale a multirotor, the harder you stress the rotor components, meaning that reliability becomes more difficult. Yeah, we are able to scale them to large sizes, but what happens if a rotor fails? For a small drone, that's not such a big deal. Even for larger drones, that's still OK as long as you don't hit anyone on the ground. You can tolerate failure rates that no passenger aircraft could ever last with. But you can't tolerate failure rates with passengers that you could with small cargo. We aren't close to having an established safety record for copter drones capable of carrying passengers that would make this commercially feasible. It's not an impossible task, but it's a really, really big one, and it's probably going to take a long time (as in decade+) to solve.



It's either a battery or a fuel cell. Nothing else is going to give you electricity directly, and a hybrid engine plane isn't an electric plane.
The inability to perform an autorotor landing is a problem for a quad/hex/whatever number -rotor drone-style craft, when manned. Or perhaps it can be dimensioned to land with one engine out. Electric motors are potentially far more reliable than fuel engines.

So far, battery or fuel cell, yes.

There are also hydrogen-burning engines, but off topic.

Hans
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Old 10th October 2023, 03:01 PM   #17
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Originally Posted by theprestige View Post
Huh. I assumed that the "turbo" in "turboprop" came from adding energy by compressing the air and then using that energy to drive something. And that electricity rather than combustible fuel could be used to add energy in the compression step. I.e., one could use an electric motor to drive a turboprop.
Nope. The "turbo" comes from "turbine" - a turboprop is essentially a turbine engine that drives a propeller instead of using jet thrust for propulsion.

https://aerospaceweb.org/question/pr...n/q0135b.shtml

Both turboprops and turbofans use the same fuel... usually Jet A1 (sometimes called AvTur in the military) which is essentially high-quality aviation grade kerosene.
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Old 10th October 2023, 04:10 PM   #18
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Originally Posted by smartcooky View Post
Nope. The "turbo" comes from "turbine" - a turboprop is essentially a turbine engine that drives a propeller instead of using jet thrust for propulsion.

https://aerospaceweb.org/question/pr...n/q0135b.shtml

Both turboprops and turbofans use the same fuel... usually Jet A1 (sometimes called AvTur in the military) which is essentially high-quality aviation grade kerosene.
Yes, the energy in the compressed air is used to spin the turbine. I know all this. I had just sort of assumed that the compression stage could be electrically driven.
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Old 10th October 2023, 05:38 PM   #19
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Originally Posted by theprestige View Post
Yes, the energy in the compressed air is used to spin the turbine. I know all this. I had just sort of assumed that the compression stage could be electrically driven.
Ah I see.

The consensus on the Aviation Stack Exchange is that it would not be a very good idea

"Are there Hybrid Electric-Combustion Turbine Engines where only the compressor is electric driven?"

https://aviation.stackexchange.com/q...e-compressor-i
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Old 10th October 2023, 05:40 PM   #20
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Originally Posted by smartcooky View Post
Ah I see.

The consensus on the Aviation Stack Exchange is that it would not be a very good idea

"Are there Hybrid Electric-Combustion Turbine Engines where only the compressor is electric driven?"

https://aviation.stackexchange.com/q...e-compressor-i
Why would only the compressor be electric driven?
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Old 10th October 2023, 08:57 PM   #21
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Originally Posted by theprestige View Post
Why would only the compressor be electric driven?
I don't know? You're telling the story

Originally Posted by theprestige View Post
Huh. I assumed that the "turbo" in "turboprop" came from adding energy by compressing the air and then using that energy to drive something. And that electricity rather than combustible fuel could be used to add energy in the compression step. I.e., one could use an electric motor to drive a turboprop.
I really can't see how that would work. The energy density of even the highest energy-density batteries would not be great enough to do what you are asking. The losses would be huge.

I really do not understand what you are arguing about here.

The example linked to by RanB is an electric aircraft called the "Eviation Alice". It uses two, rear-fuselage mounted, 100% battery operated electric motors that directly drive propellers for propulsion. In air inlet ports in the nacelles (that Ziggurat asked about) are to allow air inflow for the Thermal Management System (because these motors work very hard, and get very hot).



Front view of the starboard engine with its nacelle removed. The TMS heat-sink is
visible inside the air inlet.
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Old 10th October 2023, 11:00 PM   #22
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Originally Posted by theprestige View Post
Why would only the compressor be electric driven?
Why would you want a compressor if you don't have the combustion part? The energy is generated in the combustion stage, and then you use some of it to drive the turbine, which drives the compressor. In an electric plane all that is replaced by an electric motor that simply drives the propeller.

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Old 11th October 2023, 07:13 AM   #23
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Originally Posted by theprestige View Post
Yes, the energy in the compressed air is used to spin the turbine. I know all this. I had just sort of assumed that the compression stage could be electrically driven.
When you compress air, you store some energy in it, but it also heats up, and some of that heat transfers, so you lose some of that energy. So if all you're doing is compressing air, you're getting out less than you put in when you let it expand again. In order to get more out, you need combustion. The combustion is what gives you the net energy output.

But if you're doing combustion, there's no reason to add electricity to the equation in a jet engine. Making it hybrid by adding an electric generator to the output and using that electricity to do the initial compression just adds two conversions (mechanical to electrical and electrical back to mechanical) between the output and the compression, which is going to add weight and inefficiency. There's absolutely no point to doing that rather than just powering the compression straight from the combustion output.

Now you might ask, if we don't do that for jets, why would we do that for cars? Why are hybrid car engines more efficient than straight combustion engine cars? And the answer is that car engines don't operate like turbine plane engines. A turbine plane engine (be it jet, turbofan, or turboprop) spends most of its time operating near its peak efficiency, under fairly constant load. That's the way you design it, so that normal flight conditions match peak engine efficiency.

But cars don't do that. You're operating cars under wildly different engine outputs on a regular basis, so it's not possible to keep a combustion-only car operating at peak efficiency. If you're driving in the city, you may spend a lot of time burning fuel at zero efficiency as you idle at a stop light. A hybrid car engine doesn't have the electric motor take over part of the engine cycle, it substitutes for the entire engine cycle. It allows you to only run the combustion engine only at peak efficiency, and use the electric motor for the rest. You do lose some energy in the conversion process, but because most driving involves so much inefficient engine use that you can eliminate, there's still a net gain to be had. But if you were to run at peak engine efficiency constantly, a hybrid car would actually lose out compared to a combustion only engine.
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Old 12th October 2023, 12:09 AM   #24
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Under development...

Heart Aerospace EC-30
A full-size four-engine 30 seat short-range airliner. Its expected to have a fully electric range of 200km, which can be extended to 400km on hybrid power. If payload is cut to 25 people, range rises to 800km, all with normal safety reserves. Those ranges are likely to improve as battery technology advances.



It also it will also have two turbine powered APU's that run on sustainable aviation fuel (to supply extra electrical power) which would only be used in an emergency, or in the case of an aircraft needing to divert to an alternate airfield out of its normal range.

United Airlines has ordered a number of EC-30s* for their short haul services (conditional on it meeting safety, business and operating requirements). Air Canada have ordered 30, and they and Saab have invested in the project. Nordic airlines Braathens Regional Airlines (BRA), Icelandair and SAS have given letters of intent to buy. In New Zealand, Sounds Air has expressed interest in buying some for their Picton to Wellington run. Its just 71 km across the Cook Straight and would be ideally suited - it could make the return run with 25 passengers without recharging.

*The EC-30 is expected to enter service in 2028
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Old 12th October 2023, 01:12 AM   #25
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I think we should go back to the energy source for planes Richard Feynman nearly got a patent for.

nuclear
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Old 12th October 2023, 02:41 AM   #26
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Originally Posted by smartcooky View Post
Under development...

Heart Aerospace EC-30
A full-size four-engine 30 seat short-range airliner. Its expected to have a fully electric range of 200km, which can be extended to 400km on hybrid power. If payload is cut to 25 people, range rises to 800km, all with normal safety reserves. Those ranges are likely to improve as battery technology advances.

https://www.dropbox.com/scl/fi/p1c5q...89kp0n20&raw=1

It also it will also have two turbine powered APU's that run on sustainable aviation fuel (to supply extra electrical power) which would only be used in an emergency, or in the case of an aircraft needing to divert to an alternate airfield out of its normal range.

United Airlines has ordered a number of EC-30s* for their short haul services (conditional on it meeting safety, business and operating requirements). Air Canada have ordered 30, and they and Saab have invested in the project. Nordic airlines Braathens Regional Airlines (BRA), Icelandair and SAS have given letters of intent to buy. In New Zealand, Sounds Air has expressed interest in buying some for their Picton to Wellington run. Its just 71 km across the Cook Straight and would be ideally suited - it could make the return run with 25 passengers without recharging.

*The EC-30 is expected to enter service in 2028
The APU's certainly solve the problem of emergency range, but of course at the cost of extra weight and complexity. I think that project looks very promising but we must see how it pans out in practice. My guess is that economy will be a problem; commercial air transportation is a fiercely competitive business, and I fear such a project will need some form of government subsidiaries. ETA: A clear problem is that such a short range will be under heavy competition from modern train technology, which will be safer, cheaper, and in many instances, faster.

Still, very interesting.

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Old 12th October 2023, 03:04 AM   #27
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Do they recharge the batteries in place, or swap in fresh ones?
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Old 12th October 2023, 03:17 AM   #28
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Originally Posted by zooterkin View Post
Do they recharge the batteries in place, or swap in fresh ones?
And can you refuel them in Flight?
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Old 12th October 2023, 06:15 AM   #29
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Originally Posted by The Great Zaganza View Post
And can you refuel them in Flight?
It seems that they plan for APUs (Additional Power Units) using conventional motors, which will probably produce charge for the batteries, if the plane for some reason needs to divert outside its normal range.

Another possibility is for the APU to drive the propeller directly, which is more efficient, but requires a bigger motor.

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Old 12th October 2023, 07:51 AM   #30
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I saw a video recently about airships such as dirigibles. It's a very old idea and one that has mostly been shelved as impractical and obsolete but some people have ideas to bring them back for I guess hauling cargo mostly. Not sure it can ever really be a practical mode of transport though. Maybe for a few niche cases. The electric angle is that there would be a lot of surface area on the outsides of these balloons where you could have thin solar panels to generate electricity.

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Old 12th October 2023, 08:22 AM   #31
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Originally Posted by The Great Zaganza View Post
I think we should go back to the energy source for planes Richard Feynman nearly got a patent for.

nuclear
The closest any nuclear powered flight design ever came to reality... wasn't really suitable for carrying passengers.
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Old 12th October 2023, 08:24 AM   #32
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Originally Posted by smartcooky View Post
Under development...

Heart Aerospace EC-30
A full-size four-engine 30 seat short-range airliner. Its expected to have a fully electric range of 200km, which can be extended to 400km on hybrid power. If payload is cut to 25 people, range rises to 800km, all with normal safety reserves. Those ranges are likely to improve as battery technology advances.

https://www.dropbox.com/scl/fi/p1c5q...89kp0n20&raw=1

It also it will also have two turbine powered APU's that run on sustainable aviation fuel (to supply extra electrical power) which would only be used in an emergency, or in the case of an aircraft needing to divert to an alternate airfield out of its normal range.

United Airlines has ordered a number of EC-30s* for their short haul services (conditional on it meeting safety, business and operating requirements). Air Canada have ordered 30, and they and Saab have invested in the project. Nordic airlines Braathens Regional Airlines (BRA), Icelandair and SAS have given letters of intent to buy. In New Zealand, Sounds Air has expressed interest in buying some for their Picton to Wellington run. Its just 71 km across the Cook Straight and would be ideally suited - it could make the return run with 25 passengers without recharging.

*The EC-30 is expected to enter service in 2028
I'm straggling to think of any short haul flights in Canada that are under 200km. Only Montreal to Ottawa come to mind.
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Old 12th October 2023, 09:17 AM   #33
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Originally Posted by smartcooky View Post
Under development...

Heart Aerospace EC-30
A full-size four-engine 30 seat short-range airliner. Its expected to have a fully electric range of 200km, which can be extended to 400km on hybrid power. If payload is cut to 25 people, range rises to 800km, all with normal safety reserves. Those ranges are likely to improve as battery technology advances.

Those are some strange-looking figures. Seventeen percent of the passengers use fifty percent of the power? With 5 people can it fly 4000km?
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Old 12th October 2023, 10:01 AM   #34
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Originally Posted by Myriad View Post
Those are some strange-looking figures. Seventeen percent of the passengers use fifty percent of the power? With 5 people can it fly 4000km?
I don't think that means that if you just board fewer people, the plane can fly that much farther. I think it means that they have an alternate configuration with larger fuel tanks but fewer passengers.

But all of this is still just projections. As far as I can tell, they don't even have an operating prototype yet. I've seen plenty of electric vehicle plans fail to pan out, I wouldn't be surprised if this one fails too.
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Old 12th October 2023, 10:19 AM   #35
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Originally Posted by Gord_in_Toronto View Post
I'm straggling to think of any short haul flights in Canada that are under 200km. Only Montreal to Ottawa come to mind.
If you add cross-border flights you get Vancouver to Seattle and Toronto to Buffalo or Rochester. I'm sure there's some smaller airport routes, but yeah, doesn't seem like there's actually very many routes at that range.
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Old 12th October 2023, 10:44 AM   #36
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Originally Posted by Ziggurat View Post
I don't think that means that if you just board fewer people, the plane can fly that much farther. I think it means that they have an alternate configuration with larger fuel tanks but fewer passengers.

But all of this is still just projections. As far as I can tell, they don't even have an operating prototype yet. I've seen plenty of electric vehicle plans fail to pan out, I wouldn't be surprised if this one fails too.
This. Goes for any plane, really: If you carry less payload, you can carry more fuel.

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Old 12th October 2023, 10:48 AM   #37
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Originally Posted by Ziggurat View Post
If you add cross-border flights you get Vancouver to Seattle and Toronto to Buffalo or Rochester. I'm sure there's some smaller airport routes, but yeah, doesn't seem like there's actually very many routes at that range.
Well, Canada is a big place. Europe would be more interesting for this. Still, I bet electric trains could out-compete it hands down. We are looking for somewhere with poor surface infrastructure.

But yes. 200 km is .... ridiculous. If they can't improve on that, forget it.

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Old 12th October 2023, 02:06 PM   #38
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Originally Posted by smartcooky View Post
True, but it is a much smaller part of the equation. Over 80% of the efficiency gains from flying at altitude come from greater engine efficiency

Flying at altitude might give you better drag efficiency, but you have to get there first. Most of those gains are eaten up by the losses incurred in using battery power. It costs more power to climb than it does to fly level, and in the case I am making, short haul, very little of the flight time is spent at high altitude.



The Eviation Alice has a cruising speed of 481 km/hr. The type of aircraft it would be competing against are

ATR72 - 510 km/h
Cessna Skycourier - 389 km/h
Piper PA31 Navajo - 383 km/h

That's not a lot of difference
Also means not needing to worry about pressurization. Not sure what the cost saving there are though.

2 of the planes you listed though, all have much large cabins. I cannot see the Eviation being used for regional/feeder airline routes. It'll be for executives, and celebrities. And a Piper Navajo costs much less than this plane will.
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Old 12th October 2023, 02:47 PM   #39
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Originally Posted by lobosrul5 View Post
I cannot see the Eviation being used for regional/feeder airline routes. It'll be for executives, and celebrities.
That's hard for me to imagine. If you're rich and you want a private plane, why would you buy one with such a pathetically short range? You can't get anywhere with that. And if you're only flying it occasionally, it's not like any fuel savings are going to be important. The only real advantage this plane seems likely to have is lower operating costs, but you need to fly a lot to make those operating costs exceed a higher purchase cost. And longer ranges are only unnecessary if you're always going to be flying short routes. So regional routes seems like the only use case scenario I can see.
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Old 12th October 2023, 03:38 PM   #40
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Originally Posted by Ziggurat View Post
That's hard for me to imagine. If you're rich and you want a private plane, why would you buy one with such a pathetically short range? You can't get anywhere with that. And if you're only flying it occasionally, it's not like any fuel savings are going to be important. The only real advantage this plane seems likely to have is lower operating costs, but you need to fly a lot to make those operating costs exceed a higher purchase cost. And longer ranges are only unnecessary if you're always going to be flying short routes. So regional routes seems like the only use case scenario I can see.
Yeah... good point. I mean some celebrities might buy one like the buy a Prius, doesn't mean they always drive a Prius.

It looks like DHL has ordered some and a regional airline that does island hopping in the Caribbean, plus a charter co. And thats about it. 8 passengers*, and 290 miles is not good enough for all but a few edge cases. Sight seeing maybe?

When I think of feeder aircraft, I'm thinking like ~40ish people. Thats the smallest one I've evern been in myself.

*considering a cabin of 9 will have 1 flight attendant.

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