-Finally- an honest assessment of electric airplanes

[Bell206]

not a fule burning generator making electricity in flight.

Ha. Before you start discussing your lifetime on something, you may want to catch up on the latest electric propulsion upgrades or at least watch the video I posted for you above. There's a thing called a fuel cell that produces electricity without a generator or even a battery. The technology has been around for well over 43 years. The video shows an aircraft with one electric engine powered by a hydrogen fuel cell. There's also a non-petroleum based jet fuel out there called SAF. It too has been flying in different mixtures but United has already used a 100% SAF on revenue flights. So even if they do use a generator to produce the electricity it doesn't use any "silly" fuel as you describe. You really need to get out more.

 

[Piper Dreaming]

Ha. Before you start discussing your lifetime on something, you may want to catch up on the latest electric propulsion upgrades or at least watch the video I posted for you above. There's a thing called a fuel cell that produces electricity without a generator or even a battery. The technology has been around for well over 43 years. The video shows an aircraft with one electric engine powered by a hydrogen fuel cell. There's also a non-petroleum based jet fuel out there called SAF. It too has been flying in different mixtures but United has already used a 100% SAF on revenue flights. So even if they do use a generator to produce the electricity it doesn't use any "silly" fuel as you describe. You really need to get out more.

Then its still using fuel, so not really electric.

My electric car has nowhere near the real world range it is advertised to.
Realistically the range is 60% of what they claim.

Don't get me wrong, I would love a good plane that I can taxi up beside my house, plug into the wall ,and 24 hours later take off in it and fly 500NM under any conditions.
But I'll be dead before I can call up cessna or whoever and order one.
And when that day does come in say 700 years, the price will be outrageous I'm sure.

 

[Bell206]

Then its still using fuel, so not really electric.

So since your battery requires a fuel to recharge it, doesn't that make your battery "not really electric"?? Either way the fuel cell is still driving an electric motor just like your battery. Too much.

 

[Dan Thomas]

Well, I was alluding to the fact that flying cars don't exist yet due to reasons other than technology. Your average driver is bad enough. 40k deaths per year in the US by people struggling to navigate two dimensions of movement. No way that blurring the lines between aviation and driving makes logical sense at this point.

That doesn't stop people from making and selling and misusing personal watercraft (jetskis) or ATVs or any other recreational equipment that regularly kills people. Common sense is not very common, and the stupid sorts of accidents we see prove it. Even in the fixed-wing GA world there are far too many avoidable accidents. Play stupid games, win stupid prizes.

 

[Cap'n Jack]

Agree. The only drop-in/plug-n-play fuel source I know of that equals or exceeds conventional fuels is SAF. Its the stop gap and once it gets certified for 100% use will change a number of things flying wise at the commercial level.

I think the concept of "range" is the part that has become rather subjective of late. But what if the market accepts a new range requirement? What if the market accepts an eVTOL that is limited by battery technology and commuter aircraft that is limited by hydrogen energy density? There's a lot of money being spent to answer those questions. Time will tell.

I really don’t think hydrogen is the answer, even using fuel calls, unless you make it more energy dense. Like attaching the hydrogen to a carbon atom! Methanol fuel cells will give you decent range. When you add passengers and other cargo, there isn’t a lot of space for a hydrogen tank.

 

[3393RP]

There are some interesting developments with high energy densities and fast charging in the lab. They would work fine for a C-182 or smaller. But they need to leave the lab and get into production.

OXIS is right there. What? They're bankrupt? Oh.

Lyten made a breakthrough announcement in 2021 and claimed EV battery production was imminent. Excuse me? They're still making batteries in the mAh capacity range? Oh.

 

[3393RP]

I wouldn't take that bet unless you plan to die in the next 10 years. ZeroAvia flew a Dornier 228 with a hydrogen/electric engine about 5 months ago and Universal Hydrogen flew a De Havilland Dash 8 with their electric engine about 3 months ago. Throw in MIT's 1 megawatt electric aircraft engine is off the drawing board and in the build stage, I think there will a few more commuter size aircraft flying in the near future.

Where's the hydrogen coming from? Electrolysis and SMR use more energy than they produce.

Here's what the publication European Scientist has to say about it:

Of course, as it is supposed to be a solution to the energy transition, the production of hydrogen energy must be made from renewable energies. However, since biomass and hydropower are under increasing attack by environmental movements, it is clear that the EU’s target of almost 100% of decarbonised energy for 2050 will be based on wind and solar energy, despite their variable, unpredictable, and intermittent re-inhibiting nature.

This makes today, but also tomorrow the green hydrogen solution impossible in an open and competitive world. This is also a no-brainer for Germany. Recently in an article entitled ‘CO2 must become more expensive,’ the Frankfurter Allgemeine Zeitung reported that the German Minister of Research, Anja Karliczek, and the CEO of Siemens Energy, Christian Bruch, acknowledge that the deployment of green hydrogen technology will depend on regulation and legislation, and ‘not so much on scientists’.

https://www.europeanscientist.com/e...om-natural-gas-and-not-by-water-electrolysis/

 

[Bell206]

Where's the hydrogen coming from?

No idea. However, I think if you check, none of the alternative energy sources can be supplied or finished at rates to replace all fossil-based sources. And this is known at the development levels from my limited experiences with these new technologies. What piqued my interest was the speed at which innovation turns into flying aircraft that has been happening. Haven’t seen this level since the AGATE programs in the 90s and similarly also includes a number of global auto OEMs entering the aviation side as well. Had this part of the industry been at this level when I retired 9 years ago I might have made it a 2nd career… then again probably not.

I really don’t think hydrogen is the answer, even using fuel calls,

While I think you may be right from a chemical standpoint, hydrogen propulsion is where all the main development and money is. From what I've seen within the small circles I assist, the near-term goals for the hydrogen developers appear to be attainable with existing equipment. For example, the target useable ranges for the current H2 fuel cell flying turboprops are 300mi/500km initially with pax or cargo and 700mi/1000km by 2030. Regardless, these ranges fit more into the ongoing AAM/UAM concept than current air travel infrastructure which I think is the key in my opinion.

 

[Dan Thomas]

This is also a no-brainer for Germany. Recently in an article entitled ‘CO2 must become more expensive,’ the Frankfurter Allgemeine Zeitung reported that the German Minister of Research, Anja Karliczek, and the CEO of Siemens Energy, Christian Bruch, acknowledge that the deployment of green hydrogen technology will depend on regulation and legislation, and ‘not so much on scientists’.

Couple of things there:

-"No-brainer" is perfectly accurate here. They have none.
-Thinking that regulation and legislation will accomplish what science cannot? Another proof of the lack of intelligence.

 

[Cap'n Jack]

OXIS is right there. What? They're bankrupt? Oh.

Lyten made a breakthrough announcement in 2021 and claimed EV battery production was imminent. Excuse me? They're still making batteries in the mAh capacity range? Oh.

I don't see what point you are attempting to make. You can buy electric cars now than can go 400-600 miles on a single charge now; the original Tesla went ~250 miles on a charge. They are testing a cars now with 700-800 mile range. Battery technology is improving, no matter who makes them!

 

[Dana]

For example, the target useable ranges for the current H2 fuel cell flying turboprops are 300mi/500km initially

???
If it's a turboprop, it burns the fuel directly. A fuel cell uses fuel in an electrochemical reaction to produce electricity, i.e. for an electric motor, not a turboprop.

My understanding, I haven't followed it closely, is that fuel cells still don't have the power density necessary to power an aircraft.

The thing about hydrogen is that is not an energy source- there are no hydrogen wells- but an energy storage and transport medium. And not an efficient one, despite being "green". As @Cap'n Jack pointed out, it really needs to be attached to one or more carbon atoms to have a reasonable energy density.

 

[Cap'n Jack]

No idea. However, I think if you check, none of the alternative energy sources can be supplied or finished at rates to replace all fossil-based sources. And this is known at the development levels from my limited experiences with these new technologies. What piqued my interest was the speed at which innovation turns into flying aircraft that has been happening. Haven’t seen this level since the AGATE programs in the 90s and similarly also includes a number of global auto OEMs entering the aviation side as well. Had this part of the industry been at this level when I retired 9 years ago I might have made it a 2nd career… then again probably not.

While I think you may be right from a chemical standpoint, hydrogen propulsion is where all the main development and money is. From what I've seen within the small circles I assist, the near-term goals for the hydrogen developers appear to be attainable with existing equipment. For example, the target useable ranges for the current H2 fuel cell flying turboprops are 300mi/500km initially with pax or cargo and 700mi/1000km by 2030. Regardless, these ranges fit more into the ongoing AAM/UAM concept than current air travel infrastructure which I think is the key in my opinion.

I hope I'm wrong, but I think those people are a bit optimistic.
Here's a summary of the problem:
https://www.energy.gov/eere/fuelcel... basis, however,based on lower heating values.

 

[Cap'n Jack]

Where's the hydrogen coming from? Electrolysis and SMR use more energy than they produce.

Here's what the publication European Scientist has to say about it:

Of course, as it is supposed to be a solution to the energy transition, the production of hydrogen energy must be made from renewable energies. However, since biomass and hydropower are under increasing attack by environmental movements, it is clear that the EU’s target of almost 100% of decarbonised energy for 2050 will be based on wind and solar energy, despite their variable, unpredictable, and intermittent re-inhibiting nature.

This makes today, but also tomorrow the green hydrogen solution impossible in an open and competitive world. This is also a no-brainer for Germany. Recently in an article entitled ‘CO2 must become more expensive,’ the Frankfurter Allgemeine Zeitung reported that the German Minister of Research, Anja Karliczek, and the CEO of Siemens Energy, Christian Bruch, acknowledge that the deployment of green hydrogen technology will depend on regulation and legislation, and ‘not so much on scientists’.

https://www.europeanscientist.com/e...om-natural-gas-and-not-by-water-electrolysis/

You, and they, are making a basic error. Hydrogen is really a storage medium for the energy harvested through other means, solar, wind, nuclear, hydro, etc. You generate electricity which is used to hydrolyze water and produce hydrogen. This hydrogen could be used in fixed-location fuel cells to generate power for those "variable, unpredictable, and intermittent re-inhibiting" times. Another way of dealing with "variable, unpredictable, and intermittent re-inhibiting" is to build the infrastructure to send energy from places with excess generating capacity (more wind) to those places where the wind isn't blowing. Or use batteries to store the energy to use when it isn't needed. Hydrogen isn't a primary energy source. BTW, batteries need more energy to charge then they release too. You are going to have that problem with any energy storage. Something to do with the laws of thermodynamics

 

[Sundancer]

I vaguely remember a Peter Garrison article about electric airliners? Something like avgas having 15 times more potential energy per pound than batteries? And doesn't the battery in the Tesla wiegh something like half a ton? maybe we've overlooked some material combination that would improve that ratio - but 15 times? Or even 10 times? Someday? Maybe? But I gotta believe big brains are hitting this hard - but physics and chemistry are real.

 

[Cap'n Jack]

I vaguely remember a Peter Garrison article about electric airliners? Something like avgas having 15 times more potential energy per pound than batteries? And doesn't the battery in the Tesla wiegh something like half a ton? maybe we've overlooked some material combination that would improve that ratio - but 15 times? Or even 10 times? Someday? Maybe? But I gotta believe big brains are hitting this hard - but physics and chemistry are real.

Well, whatever batteries were in use at the time Peter wrote the article. I'm pretty sure the "big brains" working on this are chemists and physicists who know what they are doing

 

[Bell206]

If it's a turboprop, it burns the fuel directly.

My bad. I simply referred to the DASH 8 test aircraft as a turboprop... it has a H2 fuel cell powered "electro-prop" on one side and a turboprop on the other side. Post 100 has a video link of its 1st flight several months ago. ZeroAvia flew a Dornier 228 as well with an "electroprop" installed as well. And they are currently prepping their next test aircraft which is a Q400 and will fly in 2024.

I hope I'm wrong, but I think those people are a bit optimistic.

Well, they're flying an aircraft with an H2 powered engine and developed its support system. I think 2025 will be the make or break point. They're slated to be flying with H2 powered twin "electroprops" at that point and provided no bent metal and they make they're 300nm range target it will be a win for them. Regardless, I also think that once SAF receives its 100% use approval it will fast track a different line of airborne electrical generation that will exceed the H2 fuel cell method. Interesting times ahead from my viewpoint.

 

[3393RP]

Couple of things there:

-"No-brainer" is perfectly accurate here. They have none.
-Thinking that regulation and legislation will accomplish what science cannot? Another proof of the lack of intelligence.

I'd say judging from the commenter's titles and position of knowledge, they have plenty of intelligence.

They're simply saying science can't make the production, storage, transport, and utilization of hydrogen economically viable. Unless other sources of energy are artificially restricted by government action, it remains far too expensive for widespread adoption.

Of course, that's going on right now all over the world. Turn on the TV and listen to Joe and Justin

I won't bother pointing out the issues with building infrastructure for the use of hydrogen as a source of energy for vehicles. Imagine an average motorist filling up his fuel cell powered vehicle at a dispensing station with hydrogen pressurized to 5,000 to 10,000 PSI.

.

 

[azblackbird]

I won't bother pointing out the issues with building infrastructure for the use of hydrogen as a source of energy for vehicles. Imagine an average motorist filling up his fuel cell powered vehicle at a dispensing station with hydrogen pressurized to 5,000 to 10,000 PSI.

The greenies haven't a clue of the infrastructure required to refine, transport, compress, and store hydrogen. Currently 98% of hydrogen production is derived from those nasty nasty fossil fuels that they're trying to do away with. Never mind the fact that it would take acres and acres of solar panels or wind turbines just to provide enough product (via the use of electrolysis) for one hydrogen based filling station for a normal 24 hr. day. Welcome to LaLa land.

 

[Dan Thomas]

I won't bother pointing out the issues with building infrastructure for the use of hydrogen as a source of energy for vehicles. Imagine an average motorist filling up his fuel cell powered vehicle at a dispensing station with hydrogen pressurized to 5,000 to 10,000 PSI.

Ever refilled a small oxygen cylinder to 2500 psi? Has to be done slowly and even then it gets hot. Refilling a big hydrogen tank would take a very long time.

 

[Dan Thomas]

https://www.sciencedirect.com/science/article/abs/pii/S0360319917343860

The problems of temperature in filling hydrogen tanks.

 

[Cap'n Jack]

My bad. I simply referred to the DASH 8 test aircraft as a turboprop... it has a H2 fuel cell powered "electro-prop" on one side and a turboprop on the other side. Post 100 has a video link of its 1st flight several months ago. ZeroAvia flew a Dornier 228 as well with an "electroprop" installed as well. And they are currently prepping their next test aircraft which is a Q400 and will fly in 2024.

Well, they're flying an aircraft with an H2 powered engine and developed its support system. I think 2025 will be the make or break point. They're slated to be flying with H2 powered twin "electroprops" at that point and provided no bent metal and they make they're 300nm range target it will be a win for them. Regardless, I also think that once SAF receives its 100% use approval it will fast track a different line of airborne electrical generation that will exceed the H2 fuel cell method. Interesting times ahead from my viewpoint.

Yes, interesting times! I hope they meet their goals, although H2 powered planes have been around for some years, with the majority of the useful space being pressurized tanks.
This one is a fairly sizable UAV:
https://en.wikipedia.org/wiki/Boeing_Phantom_Eye

It's entirely possible that the DASH-8 type plane is the "sweet spot"- large enough to carry a reasonable number of passengers yet still have enough space for hydrogen to make the 300 nm range. Maybe. I wish them well! Unlike a few other posters in this thread, I don't mind being proven wrong!

 

[Cap'n Jack]

I won't bother pointing out the issues with building infrastructure for the use of hydrogen as a source of energy for vehicles. Imagine an average motorist filling up his fuel cell powered vehicle at a dispensing station with hydrogen pressurized to 5,000 to 10,000 PSI.

Ever refilled a small oxygen cylinder to 2500 psi? Has to be done slowly and even then it gets hot. Refilling a big hydrogen tank would take a very long time.

https://www.sciencedirect.com/science/article/abs/pii/S0360319917343860

The problems of temperature in filling hydrogen tanks.

Yet someone is managing to get it done ...see below

My bad. I simply referred to the DASH 8 test aircraft as a turboprop... it has a H2 fuel cell powered "electro-prop" on one side and a turboprop on the other side. Post 100 has a video link of its 1st flight several months ago. ZeroAvia flew a Dornier 228 as well with an "electroprop" installed as well. And they are currently prepping their next test aircraft which is a Q400 and will fly in 2024.

Well, they're flying an aircraft with an H2 powered engine and developed its support system. I think 2025 will be the make or break point. They're slated to be flying with H2 powered twin "electroprops" at that point and provided no bent metal and they make they're 300nm range target it will be a win for them. Regardless, I also think that once SAF receives its 100% use approval it will fast track a different line of airborne electrical generation that will exceed the H2 fuel cell method. Interesting times ahead from my viewpoint.

 

[3393RP]

Yet one experimental entity is managing to get it done ...see below

Rolleyes indeed.

FIFY

Did you really think this through? You are well aware of hydrogen's density. How would enough fuel to transport passengers and cargo be carried on a commuter aircraft the size of a Dash 8 or Q400?

 

[Cap'n Jack]

Rolleyes indeed.

FIFY

Did you really think this through? You are well aware of hydrogen's density. How would enough fuel to transport passengers and cargo be carried on a commuter aircraft the size of a Dash 8 or Q400?

Did you read the earlier posts in this thread? My opinion about hydrogen? I know you didn't. Try reading them. I'm skeptical, but if someone is actually flying a plane partially on hydrogen, I'm pretty sure they are collecting data about how to refuel it, how much hydrogen they can store, and the range they will achieve. They have more real information than you do!

Like I said, I'm skeptical, and like @Bell206 said, they will find out within the next two years whether it is truly feasible. I'm surprised they got to the flying part, otherwise I would have agreed with you. But I'll base my opinions on facts rather then how I wish the world would work.

 

[3393RP]

Did you read the earlier posts in this thread? My opinion about hydrogen? I know you didn't. Try reading them. I'm skeptical, but if someone is actually flying a plane partially on hydrogen, I'm pretty sure they are collecting data about how to refuel it, how much hydrogen they can store, and the range they will achieve. They have more real information than you do!

Like I said, I'm skeptical, and like @Bell206 said, they will find out within the next two years whether it is truly feasible. I'm surprised they got to the flying part, otherwise I would have agreed with you. But I'll base my opinions on facts rather then how I wish the world would work.

I'll refer back to post #3.

 

[Cap'n Jack]

I'll refer back to post #3.

Aside from your selective reading, That's how we make progress

I'm not one to tell someone something is impossible when they seem to be making progress. Maybe it won't work. But the people doing it have more real data than either of us.

 

[Bob Noel]

remember the various versions of Edison talking about inventing/refining the light bulb:

“I have not failed 10,000 times. I have not failed once. I have succeeded in proving that those 10,000 ways will not work."

 

[Salty]

remember the various versions of Edison talking about inventing/refining the light bulb:

“I have not failed 10,000 times. I have not failed once. I have succeeded in proving that those 10,000 ways will not work."

How many decades did he fail before succeeding?

 

[Cap'n Jack]

How many decades did he fail before succeeding?

Why does it matter?

 

[Salty]

Why does it matter?

I’m sorry if you can’t figure that out for yourself. But I think you can.

 

[Bell206]

How would enough fuel to transport passengers and cargo be carried on a commuter aircraft the size of a Dash 8 or Q400?

I don't recall the total hydrogen fuel weight but Universal Hydrogen (UH) has developed mobile gaseous hydrogen tanks that meet the same dimensions as a standard air cargo pod. I cant link at the moment but the intent is to replace the 10 aft seats on their Dash 8, install a cargo door, and load pre-charged hydrogen pods between flights. I believe UH is also modifying an ATR 72 in addition to another Dash 8 to handle the pods. There are also several other players in the market who are on this same path as well.

The most interesting part outside the current speed of system and certification developments is the 300nm target range of these projects. Even outliers like Piaggio, Airbus, P&W, and Hyundai are quoting these same ranges which fits more into the Advanced Air Mobility (AAM) concepts than developing a "green" replacement aircraft for the current spoke-hub system. So when you include eVTOLs into the mix (UAM) and develop a useable regional component like a H2 Dash 8 (RAM), the dots start to line up for the final part of Next Gen and similar international programs.

The ironic thing is all this innovation and AAM will probably be the saving grace for keeping the current compliment private Part 91 puddle jumpers in the air and viable. As the rotor turns we say on my side the fence.

 

[Cap'n Jack]

I’m sorry if you can’t figure that out for yourself. But I think you can.

I’m sorry that your post doesn’t make sense.

Edison succeeded in making a practical lightbulb and an initial infrastructure to support them. How long he took is immaterial.

 

[Salty]

I’m sorry that your post doesn’t make sense.

Edison succeeded in making a practical lightbulb and an initial infrastructure to support them. How long he took is immaterial.

If he continued to fail and didn’t accomplish anything else because he was still trying when he died, his effort would be in no way impressive.

Or to say it another way, I’ll bet there were many things he worked on that he abandoned because he learned enough to realize it wasn’t going to work.

I am not impressed by massive efforts that lead to minuscule results.

 

[Cap'n Jack]

I am not impressed by massive efforts that lead to minuscule results.

The lightbulb was a miniscule result?
In the mid to late 1800's, there were many people working on an electric filament light. A workable electric light was made during the Napoleonic wars- it is still used today. It is called the arc lamp. If you were around back then, you would saying the incandescent filament light bulb would never happen, waste of effort. Yet here we are!

I have news for you- nearly all engineers and scientists abandon efforts when they see something isn't going to work they will put it aside. They may work on those projects again when new information comes to light. It happens to me. Sometimes advances are incremental.

 

[Jim K]

This goes here:
https://www.avweb.com/aviation-news/nasa-axes-x-57-maxwell-before-first-flight

 

[Dan Thomas]

How about some honest assessment of the incandescent bulb?

Here's a brief excerpt from Wiki:



And it goes on from there, to Edison in 1879 and a bit more. https://en.wikipedia.org/wiki/Incandescent_light_bulb

Now, the first known attempts were in 1761. It took over 100 years to make the thing work well enough to market it.

Much of the stuff we have now took similarly long times to develop after the initial invention, and battery technology is no different. If we think that by 2025 or 2030 we will have commercially viable electric airplanes, we're daydreaming. The lithium-ion battery traces its ancestry back to 1967. The nickel-cadmium? 1899. It took nearly 100 years for the NiCad to appear in my cordless tools. It took nearly 40 years to get the Li-Ion to commercial viability. The aluminum-air battery, one of those things that lead journalists to get all excited about imminent electric transportation, was first proposed in 1962. People have been fooling with it ever since.

There were many failed attempts at powered flight long before the Wrights demonstrated that it could be done.

This stuff takes time.

 

[skyking3286]

Some of the comments by folks on battery science reminds me of reading 1960 Popular Mechanics or Popular Science. A lot of dream vaporware. The question to be asked is like aviation in 1920-1950: What do you do when 90% of the data and theory has been already discovered? Comparing the Wrights to what happened afterward seems to ignore that how often aviation ignores its own past and how the journey to the future isn't a straight line of pure progress. That air and electricity can't be made to flow where they don't want to flow without things that are too heavy, too complex or too costly.

Waiting for some future development isn't going to change things 40%. It might 10%. That 10% of this imagined new unproved, undiscovered idea isn't going to change things very much. Lipos were a jump. Doing a similar jump with different chemicals is going to be very difficult and the cost benefit ratio is going to have to work.

So sure, they pushed the envelope with new ideas, but what direction? Only to prove that the good ideas were already in practice - and they pushed the envelope to the point of showing where the edges and failures were. The fans of the ALICE. the VTOL commuters and the newest electric planes are going to be looking like those 1960 Popular Science covers in history. All it takes is money - investors who don't do the homework and people willing to throw those new dollars into a dark hole.

Thank you Tecnam for walking to the edge of the cliff and deciding that was close enough to the edge - and walking back.

 

[Dan Thomas]

Waiting for some future development isn't going to change things 40%. It might 10%. That 10% of this imagined new unproved, undiscovered idea isn't going to change things very much. Lipos were a jump. Doing a similar jump with different chemicals is going to be very difficult and the cost benefit ratio is going to have to work.

The Wrights were able to fly because they built an engine that was lighter than any other. That's what was needed: a lighter power source. But even then, the airplane barely flew, didn't fly far, was almost uncontrollable. But it qualified as the first (known) powered flight.

That engine had a very short life, too.

One other thing they did was build and use a wind tunnel. That taught them much that helped them avoid wasting time on stuff that obviously wouldn't work. These days it seems that wind tunnels have been replaced by fancy computer-generated images supposedly proving that the proposed machine will fly. The laws of physics are not consulted, and they have a habit of punishing those that ignore them.