EcoPulse Makes First Public Appearance - AVweb

The EcoPulse hybrid-electric distributed propulsion demonstrator made its public debut at the 2023 Paris Air Show this week. Developed by Daher, Safran and Airbus, the demonstrator will be used to “evaluate the operational advantages of integrating hybrid-electric distributed propulsion” particularly as it relates to CO2 emissions and noise levels. For the project, Airbus developed the battery and handled aerodynamic and acoustic integration of the distributed propulsion system while Safran is responsible for the electric propulsion system including a turbogenerator, electric power management system and six integrated electric thrusters. Daher is managing the installation of components and systems, flight testing, airworthiness compliance and analysis coordination.


This is a companion discussion topic for the original entry at https://www.avweb.com/air-shows-events/paris/ecopulse-makes-first-public-appearance

Thank goodness all the “outright” lies about battery powered planes seems to be over; thought the euphemism of “thermal engine” instead of ICE is a bit funny.

Why are so many AVWeb readers so obviously against electric airplanes? Obviously we’re not all going to be flying them in the next five years, but what if that’s what everybody is flying in 20 years? Wouldn’t that be cool?

“AVWeb readers against electric airplanes?”
Hi Brian,
Speaking only for myself: Against premature and optimistic claims of the virtues of electric aircraft. Electric -motor- technology is good and is here now. Electrical energy storage capacity: not so much. I’m eternally hopeful but, unless some miracle happens, lack of useful electrical storage capacity will keep pure elec-tech on the ground. Battery tech: Many years away.
I can make a three hour flight in my Piper Cub and arrive on short final with an hour of reserve energy in the tanks. Many/most fossil fuel aircraft have far better endurance than that.

How much is “so many”? A few out of a large group is nothing and I don’t see that “AVWeb readers are against electric airplanes”. Many aviators, on the other hand, master basic arithmetic skills and the basics of physics and therefore wonder how the dreams of green fanatics can be realized in the real world based on current knowledge. Even more enlightened people know that climate change is the main reason for the variation in carbon dioxide levels and not the other way around. No one knows for sure what the future will bring - whether the Earth will be hot or cool. That is cool.

Looked like it was covered with ice, or the paint was peeling.

Brian, there is only so much product teasing that reasonable people can tolerate from vendors. There is also the issue of prioritizing public money to support business solutions for a non-crisis. THEN there are the truly ugly “demonstrators” here that add weight, drag, complexity, and cost (to an otherwise beautiful aircraft) and tell us that it’s worth it for a few lower dB and a questionably lower emissions profile.

Like 100LL announcements, just because I’m tired of the 4 decades of announcements does NOT mean I’m against a change.

Electric airplanes are a laudable goal, but always “just around the corner”–much like the “search for perpetual motion” of the LAST century.

The physics just aren’t there o produce a useful manned long-range and high-speed electric device. Pure electric power dreams have morphed into “hybrids”–a liquid fueled aircraft with auxiliary electric motors, like this example. One must ask “WHY?” Aircraft have moved from multi-motors to the amazingly efficient single-engine high-speed pressurized aircraft–only to have that concept reversed with the addition of multiple electric motors.

The reality is that NOBODY has produced the “electric dream machine” of high-speed AND long range required for a practical aircraft. AvWeb has done its job of presenting these failed programs–but the tide has turned from optimism on these programs to a collective yawn at the latest offerings.

Let us know when a practical electric airplane is certified.

Mikko, please enlighten me to the evidence showing that “climate change is the main reason for the variation in carbon dioxide levels and not the other way around.” It seems that the ice core, sediment core, tree ring, peat bog and just about any other paleoclimate data set would disagree with your statement. I could be wrong, or maybe I just misunderstand what enlightened means, but if you’re using the classical definition, then I need to be enlightened as to how the past century of research is wrong.

I’m also curious about the basic arithmetic and physics skills you speak of, I’m guessing you mean current engineering challenges. If not, please enlighten me of these as well. Thanks.

Wishful thinking (of Mikko’s 'green fanatics [below]) does NOT turn fantasy into reality, Brian. As Art says, “we” are tired of vaporware and boastful claims that are nothing more than bravo sierra.

Furthermore, there’s no doubt that an electric motor is far more reliable than a reciprocating gas engine BUT … to get the same thrust, the ‘system’ (in toto) will likely be far heavier. Beyond that, there’s no long-term proof that the support electronics – controlling large amounts of power – are up to the task any more than the lack of energy density of current battery technologies.

“Bravo Sierrra” aka “Brown-25”

We’re at Uranus.

It’s basic Chemistry 101. Look up the Ksp of CO2 in water. As temperatures increase, CO2 is released. If you’re not a chemist and don’t have a CRC manual handy, then open 2 soda cans (one hot and one cold) and see the difference in CO2 solubility/release from water.

As it gets warmer, CO2 is less soluble in water and thus is released.
By the way, research is not “wrong” but it’s useless when the dataset is wrong. Ice core, sediment core, tree ring, peat bog, etc, are not thermometers. Using them is “a guess” at best and a source of manipulation at worst.

The reason many AV Web followers are critical of electric aircraft announcements is likely related to the fact pilots as a class are more likely than the average citizen to take a “systems” view of such things. Through training and experience they are aware that successful air travel depends on attention to every link of a complex chain.

Example: A fellow pilot is enthusiastically discussing his preparations for a family vacation revolving around investing in a new plane and flying in it to a beautiful isolated tropical island, only four hours away and well within the five-hour range of the aircraft. He explains all the reasons this will be the best vacation ever. When pressed, he acknowledges there is no airport on the island and published engineering surveys all show there is no suitable terrain for one. Would you not feel motivated to suggest it might be prudent to resolve the missing link before totally committing to the plan?

Mr. Foyt, I’m sorry your memory is short these days. I’ll paste my previous reply to your nonsense about the Ksp and soda can below, but the quick summary is that your example of soda cans, Ksp and CO2 is great for liquids. Thankfully though, we live in an atmosphere that is a gas where the chemistry/physics is different, longer explanation below (from the previous rebuttal against your misunderstandings of the chemistry/physics).

More importantly, ice cores, sediment cores, tree rings and the other data sources are actually very, very good guesses. We can correlate them precisely using known temperatures during the past 100 or so years. They are still guesses (like virtually all of science), but guesses backed by exabytes of data (like virtually all of science). Just like it’s a guess that next week the temperature in Tampa will be higher than the temperature in Ushuaia, also backed by lots of data.

I hope you’re just trolling us scientists with your Chemistry 101 examples, but just in case, here’s the Ksp lesson from last month:

Mr. Foyt, thank you for finally showing that the emperor has no clothes. I was really hoping for some research showing that global warming is the cause of rising CO2. Instead you seem to be confused by the difference between CO2’s properties as a gas, liquid and solid, while interacting with a gas (atmosphere), liquid (ocean/lakes) and solid (I’ll leave other planetary bodies out of this discussion). The Ksp of CO2 in water plays no real role in the atmospheric interaction of CO2 and the photons from the earth and sun, I’ll explain below.

But first, I do like that you included the can of coke though, it’s always a great way of explaining some fundamental physics and chemistry. Unfortunately according to both Henry’s Law which you allude to, and the ideal gas law which plays a greater role when a can is opened, don’t bolster your argument regarding atmospheric CO2.

First off, both a cold can of coke and a warm can of coke release CO2 when opened. I’m assuming by cold we mean refrigerated (not super cooled to near 0K). And by hot I’m assuming warmed in the sun or left by a heater (not superheated to a plasma or something). When you open either can, and release the pressure, via the ideal gas law and Henry’s Law we know that some of the CO2 that dissolved in the liquid immediately boils out due to the reduced pressure (same way blood boils in space despite the very low temperatures). So I’m not sure where you have done experiments showing a cold can of coke will absorb CO2 in normal conditions. In fact to get the liquid coke to absorb CO2, the canning facility has to inject it under rather high pressure which causes the temperature to rise significantly. Anyhow, enough of the coke can, it really has nothing to do with your statement about global warming causing an increase in CO2 (even if we include the oceans, the analogy is so misconstrued as to be dysfunctional).

So, in the atmosphere, CO2 is in it’s gaseous form and with photons, not liquids where Ksp plays a role. So we have to abandon that red herring and instead focus on radiative transfer. Here we just look at CO2 as a molecule, and the earth and sun as sources of radiation (not the bad kind at the really short end of the spectrum to the right, but the longer ones more towards the middle part of the spectrum we call infrared).

It turns out that by looking at the blackbody curves of the sun (roughly 5780K) and the earth (roughly 255K), and using Wien’s Displacement Law, Stefan Boltzman Law along with Planck Function (I include these for the geeks and the curious who want to look them up), we can figure out how those CO2 molecules are effectively transparent at 5780K, but act like a barrier at 255K. So that radiation (aka heat) from the sun makes it through to the surface, but the radiation from earth, is absorbed by the CO2 molecules in the atmosphere (and yes, even more so by other molecules including H2O, the most effective). Because of the physics behind electrons getting excited, the CO2 molecule increases it’s vibration/energy. As explained in other comments, increasing the energy of a molecule is the definition of increased temperature. This radiative transfer process where CO2 is transparent to incoming radiation, but absorbs outgoing radiation is the same process that allows a small glass building in the back yard to be transparent to the incoming radiation from the sun, but opaque to the outgoing radiation from the ground, and we call it a greenhouse.

So as you can see, it is not the Ksp of CO2 in water, or the can of coke, but how the CO2 in the atmosphere and black body radiative transfer physics that demonstrates irrefutably that an increase in CO2 raises the temperature of an gas. Now we can debate if that raised temperature is good or bad, but you cannot debate the physics, and nobody does, at least on this planet with our current knowledge of Newtonian physics.

Now in reality this is a good thing, it is this physics that makes life as we know it possible on the surface of the earth. This radiative transfer has made the planet warm enough to live on. And thankfully because CO2 is a trace gas and doesn’t absorb too much of that earthly radiation, we’re not in a Venus situation where CO2 is the primary gas in the atmosphere and spacecraft melt/die in minutes because it’s really hot, like damn hot.

So, in the end, blackbody physics and CO2 is not the same as aqueous physics and CO2. So Ksp not so relevant, Mie and Rayleigh Scattering very relevant.

  1. We live on a water planet. That’s why the Ksp is the answer to warmer equals more co2.
  2. The atmosphere is not a closed system.
  3. Do your own research on historic data and beware of using tree rings with any order of scientific precision.
    4)Surface warming without atmospheric warming negates the theory that warming occurs first in the atmosphere.

…and it doesn’t take hours to top off the fuel and launch again, if you’re travelling beyond one fill up’s range. Recharging time is another limitting factor.

Thanks for the repost; I was thinking of it when I saw your reply - and I enjoyed the new intro.

“The Ksp of CO2 in water plays no real role in the atmospheric interaction of CO2 and the photons from the earth and sun”

That is of course a true, but think it through. It’s when there is a warming that the oceanic CO2 is released and THEN it will interact at some level with radiation from outside of Earth. Warming releases CO2; cooling sequesters it. Basic chemistry.

Good, once again we see that we can agree on things.

  1. It’s nice to see that you agree that the planet is warming due to more CO2 in the atmosphere. In your case you believe that this is because the oceans are releasing it like a soda can. Again, some pretty basic physics here disputes this, and in fact the oceans are a massive carbon sink where a very large chunk of atmospheric CO2 ends up being stored these days. Of course this likely won’t last forever, so eventually your example may come to be, then things will get even worse (search for: the oceanic sink for anthropogenic CO2 from 1994 to 2007, if you’re curious to learn more).

  2. Agreed, though not sure why you included it. My example pointed this out.

  3. Agreed, I did my own research on historic data, for many, many years whether on ice sheets, forests or lakes. Not sure if you mean all historic data or just tree rings. I personally have only worked on projects involving ice cores, lacustrine cores (mostly pollen stuff), and tree rings, so definitely not an expert on all of them. But if only I had a nickel for every ice core I’ve had to slice, or dendrochronologist I’ve had to help core trees, well I could at least buy a really nice dinner. The ice cores and tree rings in particular are impressive with their correlation as we can look at recent weather observations and see how they match so very well (mostly dealing with O16/018 ratios since you seem to enjoy chemistry) going back over a century. With the sediment cores, again we use chemistry and back it up with pollen record, and low and behold, as it gets warmer or colder according to the chemistry, we wee the pollen of plants that grow in warmer or colder environments. It’s almost as if the data has been tested and tested and tested and just keeps on agreeing.

Again, these sources of historic data have been debated and debated for many decades and are accepted as extremely reliable by the science community.

  1. Okay, maybe we don’t agree on this one. Though I’m not entirely sure what you actually are trying to imply. Every morning when the sun shines the surface of the earth warms before the atmosphere above it, not sure if that’s what you mean, but if so, then I agree. That gets back to my radiative heating stuff above. Though, it seems you have a hypothesis about something, I’m not sure what, without any data to support it. So I’ll stick with my theory that is based on a hypothesis that is backed up by more than a century of research by thousands of researchers producing yottabytes of data demonstrating that we need to encourage people to read more so they can have a better appreciation of science and the world around us.