Electric Airplanes: The Elusive Promise

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I read a quote the other day that said agnostics are just atheists who don’t want to be called atheists. Rings true for me, I suppose, but I need to retool the definition away from applying agnosticism to religion and apply it to airplanes. I further will add the word hopeful to my agnosticism and that describes my attitude toward electric airplanes at the moment.

That’s what propelled me to interview my KITPLANES colleague Paul Dye for this week’s video. I think it’s worth 25 minutes of your time to watch. He has just completed an experimental project to install an electric motor in a Xenos motorglider kit. That airplane is otherwise powered by an AeroVee, a Volkswagen conversion, or a couple of other hydrocarbon choices.

As detailed in the video, the motor came from a Zero electric motorcycle, as did the battery and electronics. What got my attention is that Paul told me his initial flight data and some quick reduction suggests that if such a thing were installed in an airplane like my J-3, 30 to 45 minutes of flight would be possible. Really? I have no intention of doing such a conversion, but those numbers are the sweet spot for a Cub, since few of us fly them much longer than that on a typical flight. I wasn’t thinking of emissions or cost of operation but of a shard of market potential based on capability.

Unfortunately, reality intrudes for everything electric, including cars, but especially motorcycles and airplanes. When we discussed the numbers for the Zero/Xenos pairing, it looked to me to be the perfect duty cycle. Fly it to say, 3000 feet, pick up some thermals or ridge lift, and have a ball for a few pennies worth of energy. What’s not to like? As it always does, endurance—lack of it, that is—tarnishes the momentary joy.

Paul lives in an area unsuitable for soaring, thermaling or otherwise. Typically, a motorglider like Diamond’s HK36 or a Stemme S12 could be flown directly to a better area for green air and if that required refueling, no problem. Just land at any airport and top off. But the eXenos lacks the range do that practically, at least out west, and because 220-volt charging current is likely unavailable along the way. It’s not available in my hangar, either, for my imaginary eCub. To be fair, this may change in our emerging all-electric future, but it’s not there now.

The sailplane pilot’s solution to this is quickly detachable wings so the entire airplane can be loaded into one of those long trailers and driven where soaring conditions are good. This is a standard weekend for sailplane pilots. But the Xenos doesn’t have quick-detach wings so it’s a prisoner of the place where it was built. EAA wanted to display the airplane at AirVenture, but Paul said they’d have to send a tractor trailer to retrieve it.

Still, despite its immediate practicality, the Xenos project is the essence of experimental aviation and is more cutting-edge than the vast majority of projects. I wonder if Zero ever thought anyone would be creative enough to repurpose the guts of its motorcycle for an airplane and therein lies another problem. The company wants nothing to do with supporting it. So when the battery pack finally cycles out, will another be available? It may be a moot point because the airplane may not fly enough to reach that point and, in any case, it can always be converted to a gasoline engine.

The Xenos is by no means the only electric experimental airplane out there, but there aren’t a lot just as there aren’t a lot of electric LSAs, with Pipistrel leading the market. I’ll pause and define a lot: Pipistrel has trickled enough electric trainers into the world, 17 in 2022, and a few dozen before that, to make a legitimate claim of having fleet experience.

One barrier to experimentation in electric aircraft is the battery systems. Brushless motors—light, powerful ones—are becoming everyday technology, but building a safe, reliable battery pack takes expertise. The battery management systems that dole out the power and oversee charging require careful logic to keep them from overheating or, worst case, igniting. It’s nothing like plumbing two tanks to an O-320. The attraction of the Zero powertrain is that they’ve already figured all that out, including the instrumentation.

And speaking of Zero, even though I’m a hopeful agnostic, I’m not a customer for an electric motorcycle. Yet. I like to run around the mountains for 300 miles a day and the Zero won’t do that, despite its impressive torque. Same for the Tesla cars. A friend recently chided me for buying a new ICE car instead of a Tesla. But the Tesla was $10,000 more and it won’t do the job of trailering my non-electric motorcycle to the mountains in a single day. Lack of range further tanked by towing would make it a full day plus a little change sort of trip. Nonetheless, I’m an admirer of Tesla’s cars and the practical technology built into them. They have a meaningful share (about 2 percent) of the automotive market.

I would have said electric airplanes are unlikely to achieve the same. Except—and this surprised me—they already have. Scanning GAMA’s figures for airplanes I take to be trainers, I came up with about 450 in 2022. It could be higher or lower because I can’t determine how many 172s and Piper Archers are bought for non-training purposes. So if the 450 is a fair guess, Pipistrel’s electrics already have 3.7 percent. Given the tenderness and limitations of these aircraft, that’s not a bad showing.

Some flight schools are making them work, but it requires too much compromising in how the airplanes can be used to be broadly practical. Yet. And if all this is being done solely in the name of emissions reductions, I think broad use is still over the horizon. What we’re seeing now is early adopter buying. I’ll concede that operating costs may swing in favor of electrics across a narrow band of the training program, but I’m not sure the savings are worth it overall. I remain open-minded.

And also hopeful. I’ve never been one to heap scorn on electric airplanes—or cars or motorcycles—for their considerable shortcomings. I’m just not a buyer yet. We should all be happy to see experimentation and development in electric aviation because for every dozen dead ends, there’s a true breakthrough in aircraft propulsion that stumbles us toward an uncertain future. And we should all cheer that.   

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67 COMMENTS

  1. I share your ambivalent feelings about the future of electric flight. Years ago there was a TV show on PBS entitled “Connections”, which looked into the history of some of the modern devices that we take for granted today. The main thread through all of the shows was that any major inventions like the light bulb, air conditioning and even airplanes came about when all of the technologies involved were either discovered or invented. Up to that point, even though people could conceive of the device, the technology did not exist to make it happen. It seems that electric aircraft are at that point today. The electric motors are ready, the power distribution and control systems are well developed, but those damn batteries are just not ready for prime time. And knowing a little about chemistry, I wonder if the current lithium based batteries will ever reach that critical mass. Experts maintain that battery capacity is increasing about 5-7 percent each year – nothing like Moore’s law on computer power. At that rate, a suitable battery is more than a decade away, and I doubt that the current pace can even be maintained. The problem is twofold; power density and weight. It may be okay for a car to lug around a half ton of batteries to get you maybe 300 miles of range, but our current avgas engines can get me over twice the range on a quarter of the weight in fuel. Without some major breakthrough in power storage density, that is a hurdle I don’t see us crossing any time soon. Don’t get me wrong, I would love to ditch my archaic IO-360 and all its fiddling and mess for a clean, emission free electric motor. I’m waiting for someone to announce they have found a major source of unobtainium before I start my engine conversion.

    • George Bye promised me an electric quick swap conversion for my 172 over a decade ago at Airventure … I’m STILL waiting for it !! Erik Lindberg briefed our EAA chapter on how his eVTOL people movers were gonna darken the skies in urban areas and SO far, it hasn’t happened. As you say, John, it’s one thing to try to make that idea work in a car where you mostly aren’t fighting gravity over and above the motive needs; an entirely different proposition in an airplane. The first time an airplane goes down in flames because the battery pack decided to self-immolate OR an airplane flown by some student pilot runs out of electrons and couldn’t make it back to the airport, the tune will start changing. Just because the ‘ normal’ mission in PB’s cub isn’t an hour doesn’t mean that there couldn’t be times when the other 2-3 hours of fuel in the tank doesn’t save his bacon. Heck … he might fly into that “black hole W of Venice and need the fuel to find the peninsula?

      Myself, I’m a corvette guy. The new eVette sounds mighty interesting UNTIL I think about how complicated all those systems are. I’ve already read articles about people having problems with Teslas and having a helluva time finding a dealer / mechanic who knows how to change batteries in his flashlight without electrocuting himself or using electrical tape. One guy in St George, UT had to have his car towed to Las Vegas because the systems wouldn’t let him open his charging port door. GEESH !! And reliability of ANY system is directly proportional to the parts count / complexity of said system.

      I’m not an agnostic, I’m an unclean disbeliever. I’ll go a step further … MY position on eAirplanes parallels this notion:

      msn.com/en-us/news/world/net-zero-is-a-trojan-horse-for-the-total-destruction-of-western-society/ar-AA19eKvr?

      Just today, I read where research on battery chemistry is yielding some positive inroads. Swell … but until we’re not using lithium or other hard to get/mine materials, at some point we’re gonna run out of the rare materials to make the darned batteries, too.

      Now then … I’m going flying … my trusty O-320 awaits me …

      • Like you, Larry, I read a couple articles each week about the new innovations and discoveries in battery technology. Some of that research is going into finding more common materials that would yield “safer” batteries that are more tolerant of everyday use and abuse. But the simple fact is that lithium is the material on the periodic table with the highest chemical potential, thus the one most likely to produce the most power per pound of electrolyte. Yes, a safer battery is nice, but one still has to remember that E-car battery packs operate at voltages from 400 to 900 volts – enough to electrocute you, or to start a fire if shorted or grounded to the wrong place. Substituting electrons for carbon molecules does not necessarily make the system any safer. Be nice to that O-320. It will be with you for quite a while to come.

        • The volunteer fire dept in the town I summer at in WI has strict instructions to the fire fighters. “IF an EV catches fire, get the occupants out and let the vehicle burn.”

          I read something about research on zinc anodes today. I don’t doubt that — ultimately — some breakthru might be achieved but the current design of batteries … FUHGETABOUTIT !!

        • John
          I agree with you. That annoying chemistry and physics always rears its ugly head. I do think there will be moderate incremental advances in battery chemistry but probably not enough to make e-aircraft practical in the near future.

    • Let’s think it thru
      How much endurance do you expect left after landing?
      Allowing for all contingencies I would say 20 minutes so your 45min becomes a do-able 25 min. Not enough.

  2. A comment regarding Paul Bertorelli’s article about Paul Dye installing an electric motor in a Xenos motor glider. At one point in the article Mr. Bertorelli says “Paul (Dye) lives in an area unsuitable for soaring, thermaling or otherwise.” As a glider pilot myself, living in Reno, NV, I happen to know that Paul Dye lives between Reno and Minden, NV. This area happens to be one of the MOST SUITABLE areas for soaring (thermaling or otherwise) in the world. I have personally had thermal flights in my glider to more than 17,000 feet MSL on many occasions and have flown a distance of 460 statute miles (which is not really much in these parts) using thermals. Just 3 weeks ago, a glider pilot flying out of Minden, NV, made a flight of 1,301 statute miles using mountain wave.

    • On the macro scale, you’re absolutely right James – we live in an incredible soaring soaring area! Unfortunately, on the micro scale, the area right around Dayton Valley Airport is a dead zone for low-performance sailplanes. The Xenos is about 26-1, so not a great soaring machine, and we have to climb significantly to get “over the hill” to Minden to pick up ridge or thermal lift. We get lots of “land outs” at our airport every year due to folks who just couldn’t quite get out of (or over) our valley to the good lift. We’ll get the eXenos out of the valley when we reach that point in the test program, but we’re still staying close to the nest right now. The rough gouge is that it takes about 10% of the battery power to climb 1,000’, so planning some reserve, that gives about 7,000’ of climbing to find lift.

      • Hey Paul, you are absolutely right. I was only looking at the big picture. I know from flying gliders cross country in this area for the past 40+ years that the area around Dayton (and from there over to Silver Springs) is a “sink hole”. When the wind blows out to the west, southwest on a summer afternoon (as it often does) the area from Dayton to Silver Springs is like a venturi that wipes out the lift. One needs to jump the gap from Virginia City to Raw Peak and vice versa. FYI: it has been a long time, but I have also landed a glider at your nice airport:)! Safe flying to you!

  3. The Pipistrel with current battery technology might not be the answer to all training needs but being able to fly training patterns with negligible fuel cost and emissions is quite something. Battery technology is going to improve. When the first electric airplane flew in the early 1970s, it did so with lead-acid car batteries and had about 10 minutes endurance. When I was young, NiCd with their “memory effect” were a nuisance but the only thing we had. There’s better to come. If we need it and there is a market, research will eventually bring about better products. I don’t believe in all that e-powered air taxi stuff, less so for the electric aspect than for the pracicalties of sending hundreds of pilotless vehicles operated by competing companies around urban skies.

  4. Christ! The myopia expressed in both the article and comments is just the same nonsense spouted about electric (road) vehicles 10 years ago and, for that matter, about trains in the mid-nineteenth century “ONG!! Traveling at 40 mph will kill you!!!” Remember?
    Certainly practical battery electric aircraft capable of long distance are unlikely to be available for the foreseeable future (other than dirigibles, of course) but aircraft such as the Eviation Alice and Pipistrel Velis/Alpha Electro prove you are all wrong as these aircraft exist now and fill at least 2 very important niches in aviation; training and short haul commuter roles, the latter of which makes up 50% of the USA aviation passenger miles. Just like electric cars, it will not take long for the competition to hot up and battery chemistries with almost twice the energy density are already in electric cars being launched onto the automotive market as we speak. In an aircraft context these will permit solid 500nm range at ~300mph, not up to kerosene-powered jet aircraft but nevertheless a very significant step toward ending aviation’s reliance on fossil fuels and cleaning up the environment.

    “Let it burn”. Well, yes, if it makes no difference to anything/one else quite right… or do what every competent electric vehicle workshop does in the real world and dunk the crashed vehicle in a 2′ deep tank of water. Anyway, just how many carbon fuelled-aircraft survive a post-crash fire? Newer battery chemistries offer far greater safety than conventional aircraft fuels.

    It is simply exasperating to hear intelligent technically minded people witter on about this sort of tripe all over again. *LOOK AROUND YOU* – EVs are quite literally taking over the planet – and about flipping time!

    • Did you actually read the article? “I’m a hopeful agnostic, I’m not a customer for an electric motorcycle. Yet.” and the rest of the article cheers electric development, but also states the reality that it isn’t there yet for airplanes. Read that last paragraph. It’s hardly myopic to point out that the tech just isn’t there yet for this application. It’s barely there for automobiles.

      There was an electric fad back in the 1970’s and early 80’s, based on lead-acid batteries though. I knew someone that had an electric, and they would get it out once in a while to drive into town. It was an oddity then, and kind of weird when I was pedaling my bicycle and this quiet vehicle passed me. Yes, an electric could pass a bicycle back then, just not a gasoline-powered vehicle. 40 years of development and now we have some pretty decent electrics, even if they aren’t as convenient as gasoline powered vehicles. I saw a Tesla towing a decent-sized camper the other day. I remember thinking, ‘He has the torque to do it. I wonder what his range is pulling that.” I bet he had to do some careful planning! But it’s progress until we figure out a new Tom Swift invention that makes spinning a propeller for movement old news. (Did I just date myself? I guess so.)

      • I have a friend that recently bought one of the Ford Lightning pickup trucks. Very nice vehicle, and insane acceleration. But, if he tows something up to the tongue weight limitation, his range is about half of the empty truck distance. That is not unlike a gasoline or diesel truck doing the same, but planning for the frequent charging stops and the time involved at each, it doesn’t exactly encourage mainstream adopters. Electric vehicles are making huge strides, and new innovations are coming all the time, but there are still major hurdles to overcome if we plan to meet the government’s goals of all electric by 2040 or so. And that is just for cars. Adding electric aviation to that mix adds yet another layer of complexity.

  5. The motors are getting more efficient and, more, reliable than heavy old ones with brushes and bearings that needed constant watching.
    Control systems for motors have come on leaps and bounds, and with AI driving software development, will probably see another leap forward.
    That leaves the batteries, or other power source — fuel cells anyone? They work in space but not on land — which always seems strange.
    For the batteries and systems, the Zoe, the €5 billion development cost little car from Renault (going for a little car was a huge strategic mistake,) went from 90km effective range to 240km between 2013 and 2017, through advances in battery technology and putting more batteries into the thing.
    Since then it has stuck, although new “dry” batteries being promised by Saft and others might change the game again in 2024.
    So progress is slow, and even slower when applied to aircraft. What is not slow is the change in public opinion.
    People used to laugh at drivers of diesel trucks who “roll coal”, when they pass people they think are not like them. Now they call the cops.
    Not long before the cops are called every time people hear aircraft, especially noisy ones being used for fun and looking down on the neighbours….

  6. Very simple for me. I get nervous when I only have 1 hr. fuel remaining in my Lake amphibian so hardly interested in an aircraft that that has 1/2 hr range to start with. I used to ferry aircraft to Europe and Australia with up to 20 hrs of fuel; that is comfortable.

  7. Going out on a limb here, but I believe once the initial issues are addressed and electrics come into a little more common usage. we will see that electrics are suitable for some operations and not for others, just as turbines are more suited for some ops and pistons are more suited to others. It’s likely optimized roles will make operators of the various modes of powering aircraft totally happy. But that will not stop the acolytes of electric flight from continuing their harangue. I have talked to two individuals who engineered and flew their own electric powered homebuilts and neither assumed they could speak for all pilots, nor the entire industry of Flight. I did some prelim investigation & study about installing a FES system on my glider, either the commercially available “official” FES or if I could engineer a comparable system on my own. The cost would be more than what I have in the glider now, so, No. Most of the “early adopters” whom I encounter claiming to represent The Future Of Aviation thru electric power and that the rest are Olds, Dinosaurs, etc. do not fly anything large enough and powerful enough to carry a person, if they fly anything at all. The attitude of “You all will have to accept what I have accepted” is a control trip and that attitude has been enough for me to practice the tool of Avoidance when it comes to the electric trend as it exists right now.

  8. * Electric motors and affiliated electronics: No problem, we’re there.
    * Storage capacity for the sparks: . . . A -very- long ways to go.

  9. We cannot equate electric cars to aviation. The batteries weigh too much and there is no regenerative braking. But there are a few things aircraft has that cars do not. So far, these have been ignored because the focus has been on what EV.s are doing on the ground. The solution is very simple and coming very soon at an affordable price.

  10. We’ll keep reading that stuff about electric cars and planes though. I mostly just scan that news though, unless it seems plausible. I’ve flown an electric plane, but wasn’t impressed. I was impressed with the accelerations of the Tesla, but not the rest of it.

    As for me I’m not an agnostic or an athethis, but a Believer and a sinner.

    Just not a believer in buying an electric airplane yet!

    Warm Regards to Ya’ll, You too Paul.

    Tiger

  11. I believe electric motors are a good way to power the transportation sector. Unfortunately they’re hamstrung by batteries that have many limitations that are well known. One that seems particularly relevant in aviation is the loss of energy on very cold days. Also, I’d be hard pressed to trust an aircraft that is almost bingo fuel before it’s even airborne. Sure it can go 140 miles? Over three decades of flying my final destination was almost always viable. A few times it wasn’t but the Arrow’s long range made it easy to get to an alternate.

    I just hope government does not begin to push electric aircraft on us as they are doing with cars i.e. California will ban ICE’S at a certain year. Someone here mentioned electric planes are not ready for primetime and likely will not until a new source of energy comes online.

    • I’m not sure a ban on ICE vehicles by a state will hold up to the 10th amendment. Will be interesting to see.

      • The 10th amendment is a restriction on the federal government. How would an individual state’s actions run afoul of it?

  12. The new technology adoption curve for electric car is rapidly moving out of the “zealot/early adopter” phase into the :has early adopter” phase. This argument reminds me of the adoption of solar power augmentation for homes phase which is now a widely adopted. The one disconcerting vein I see is that, as we run at breakneck speed destroying the ability of this planet to support humans, more people are not willing to take even small steps to slow down the impact on the planet–the only places so far that can support human existence. Over the last five years I h ave changed from two diesel vehicles (truck & car) to electric replacements which are charged at home (mostly) by the solar system I put in over 20 years ago (still going strong). Aviation, particularly general aviation has not changes all that much since my 1947 PA-12 was built. Only slight improvements in efficiency along the way. We still do not know how long the current crop of Li-on batteries will be useful but, they all are recyclable & a very high percentage of the materials can be used in the next generation of Li-on batteries. Mot so much with gas. Current car (including the electric ones) will likely be used for 200,000 miles. That is somewhat more than my old ’55 Chevy could have made it, short of major rebuilding processes along the way. Efficient electric airplanes are coming & my Supercruiser will eventually be a museum piece along with my 6mpg DGA-15P. The only thing that is constant is change.

  13. I see little mention of the hybrid. Yes, weight will be a factor, but gas/electric hybrid cars were one of the successful transition points between ICE and fully-electric automobiles. Takeoff and climb with both and cruise with electricity.

  14. Slightly amused about the comments and one particular commenter asking another if the article was actually read… I remember quite well the flood of (at times nasty) comments received upon haplessly penning my E-Everything vs. Common Sense article, which triggered certain individuals to come out with their bazookas in order to progressively educate the un-knowing. I was young, I needed the money…

    Quite a few years have passed, albeit I was never truly a die-hard anti-climate- rescue- blasphemer, nor anything else than politically independent, I still see no really groundbreaking development, other than a change in how we have lost our ability to accept different opinions.

    Unpopular opinion: E-Everything is bound to fail. We cannot develop stuff quickly enough to adjust for the inflationary use of politics in forcing all these changes upon everyone.

    Has progress in E-Mobility been made? Absolutely. I spent time at AERO marveling on the newest of the new stuff. I won’t even try to outrun that amazing 700hp Tesla on the German Autobahn, yet I cruise by him when he spends 25 minutes at the charging station… Are we anywhere close to seeing General or Business Aviation aircraft being powered by electricity? What abou flight schools? What about Air Taxi? What about Part 91/135 Charter? Wake up!

    When it comes to propulsion systems in use, we are squarely back in the 50’s. Lets not talk about the 25 year old saga of replacing AVgas 100LL.

    We got very very fancy airframes and shiny cockpits for sure, but the thing that moves the fan on the front is a technical dinosaur. I am one of the poor souls who love the smell of burned AVgas (probably brain damage, who knows?) however our Last Generation isn’t amused and they are refusing to inhale it and their ideas of the future of aviation is nowhere in the psychological vicinity of (y)our worst nightmares.

  15. Lots of comments, but the really big problem is recharging the battery at the destination, or at the home airport.
    Motors and controllers are now available to power a Cessna 172 or PA24, with 150 to 200 HP.
    Even if a breakthrough battery is developed that weighs the 300 lb that 50 gallons of avgas weighs. it will have to supply about 550 kWhrs of power for about 5 hours of flight.
    That will require a Tesla style ‘supercharger’ of 250 kw to be able recharge the battery in 2+ hours.
    Most hangars have 120 volts, and 20 amps service, [ 2.4 kw], so it would take over 9 days to recharge.

    What Airport will pay to have this high capacity charger , [ or 2-3 of them] , installed ?
    A 250 kw unit will need a 480 volts, 500 amp connection to the local distribution lines.
    I doubt that most airports have the access to the needed capacity without a major power distribution upgrade.
    BTW, most high capacity DC chargers here in CA are charging about $0.50 per kWhr, so that 550 kWhr battery recharge will cost $275 today, vs the $ 325 for 50 gallons of avgas.

    So, I’m sure that we’ll be burning avgas for a very long time…

    • We musta been ‘pecking away’ at the same time, Jim? And, we agree … again. 🙂 I had no idea they were charging THAT much for electrons out there!

      • PG&E is charging us a residential rate of $0.32 /kWhr, for the 1st 360 kwhr, then $0.40 for over that.
        So, it’s common to have a $200 electric bill, with no a/c or heating running.
        With the 100 Deg. summer days, the a/c can add another $100 to the bill.

        • Those numbers astounded me, Jim … so I dove into it. I’m paying ~$.12 in both FL and WI just for the juice; only a bit more all in ($ / KwH). I happened to have a bill for a friend who has solar on the roof in LA and see they have numerous time-of-day rates ranging from $.09 to $.20 but the DELIVERY charges seemed excessive. You musta divided your total bill by per KwH used ??? Is that so ? BTW: Their solar installation made their bill FREE !! But that system wasn’t cheap.

    • Another option is hydrogen fuel cells to overcome the battery penalty or Plug Power’s fuel cell powered battery charging stations if battery weight reduction makes the advances needed?

  16. It’s one thing to carry around > 1,000 lbs of batteries in a Tesla … quite another to try to convince me that it’s OK in an airplane OR that Moore’s Law as applied to batteries will make their energy density an order of magnitude better any time soon to make it practical. Beyond energy density is charging time (although replaceable battery packs could fix that), ability of the grid to absorb the growth in electrical demand, amount of the raw materials on the earth to build enough batteries, ability to build enough batteries, ability to recycle old batteries (I don’t believe we’re there yet), range anxiety, impact of cold temperatures on efficiency and more. These are all very real impediments to implementing a radical changeover to electric power for motive force. Unless and until a ‘system of systems’ approach and five, ten and longer plans are put into place, this idea of electric propulsion being feasible in aviation (beyond special purpose) is nuts. You wouldn’t power a DJI drone with a 327 ICE any more than you’d power an A380 with electric power. Each has a place. From MY perspective, until we start building small nuclear reactors and modernize the grid … everyone is just flapping their jaws.

    At my small airport in WI, they’re filling in ALL of the empty land with PV solar collectors. Swell … but what about night time? What about how much raw materials needed to make all those collectors and install them? I see cars up there SO rusted away from road salt that I wonder how they stay in one piece. No one will ever be able to convince me that it’ll be possible to keep that salt out of the motors and electronics. There’s a Tesla super charging station at the Menards shopping center in Oshkosh; I never saw it in use until maybe two years ago. So I walk over and talk to the users to see what I’d hear. One of ’em was from Oshkosh so I asked him what does he do when its -25 deg F in winter … he looks me right in the eye and says, “I can work from home.” Another was mad because he had to tell his car where he was going and the car then tells him how to do it. THERE’s your problem. Moving back to airplanes, there are greater issues to solve and we ain’t anywhere near ready. THAT was Paul’s premise.

    My point here is that we haven’t solved all the allied logistical issues in any major changeover to make however many ground vehicles (forge about airplanes for a moment) exist on the planet to electric and we don’t have long range planning for it either. Merely waving your ‘magic twanger’ (froggie) (google it) and mandating a date certain for the adoption of electric vehicles is MAD! MAD!

    I have enough ICE vehicles to last my remaining time on the right side of the grass … and I ain’t parting with my 7.5L 460 Ford truck EVER. Those who think this electric everything notion is a good idea … knock yourself out … I’ll wave when I go by. And when the stores in Kalyfornya are empty because there are no diesel 18 wheelers to deliver … I’ll laugh.

  17. Specifics aside – my experience is that most GA aircraft have about 4 hours usable range. Unless and until Electric aircraft can match that they’ll never be a commonly accepted replacement. The buy/don’t buy decision needs to become based on the standard considerations that most buyers currently look at. Currently the buy decision is almost always politically or tech zealot based. We all want it to be practical, but as most married men know, wanting something doesn’t make it so.

    Sorry Paul, but 45 minutes range isn’t even close to being safe – much less practical. I’m one of those who even VFR has to land with at least an hour left. I’m not about to give up that safety margin to look like I’m cool and hip.

    Someone IS going to invent a new energy storage concept that will revolutionize everything – someday. Time limited legislation is stupid bordering on irresponsible. Innovation cannot be created by legislation. It comes when it comes – and it will come. But it ain’t here yet and it doesn’t look like it’s going to be ready anytime soon.

  18. I’m an atheist concerning all sort of electric vehicles (aside trains – they do not need to carry batteries to moove them), just for the reason that so soon science and industry has not, yet, be able to comply with the energy/power and weight needed for them. May be science and industry, based in some form of nuclear extraction of that “triangle” should in a (for me long) future achieve that. If I will be alive then, may be I’ll turn from atheist to agnostic. Until then …🤔🤔🤔

  19. From Business Insider:

    “Billionaire Bill Gates, one of the world’s foremost investors in sustainable technology and owner of a $40 million Bombardier BD-700 Global Express, pushed back on the characterization that private jet travel is incompatible with climate activism, noting that he purchases direct air capture carbon offsets that “far exceeds” his family’s carbon footprint.

    The National Business Aviation Association, a trade group that represents the private aviation industry, has pledged to to achieve net-zero CO2 emissions by 2050 through initiatives such as increasing fuel efficiency, supporting green tech such as sustainable aviation fuel, and purchasing carbon offsets.”

    Hallelujah … all we here have to do is purchase some carbon offsets and suddenly our CO2 spewing GA airplanes, et al, are OK and we don’t need batteries. Now if planting a tree (which eats CO2) to get a carbon offset works, what’s gonna happen when we do away with all the CO2 emissions and trees start going hungry ??

  20. Ultimately electric airplanes will prevail where the economic case make sense. Flight training is an obvious place to start. A short duty cycle with a majority of the flights are out and return are tailor made for a flight school.

    As was noted above the elephant in the room is batteries. The motor and motor control systems are done. The trick is to find the sweet spot for battery weight vs capacity vs cost. Are we there yet, hard to say, but worst case is we are definitely close, especially for flight training.

    The flying club I belong to in Canada puts 1000 hours a year on their C172’s. That’s 10 oil changes, 2 500hr Mag inspections, plus lots of other engine bits and pieces. Every 3 years they will spend close to $50K CAD to overhaul the engine. Each hour of flying will cost $ 70 for fuel.

    An electric airplane will cost less than $4 an hour for power and requires almost no power train maintenance. So the 64K question is how long will the battery pack last and how much will it cost to replace. FWIW the numbers I am hearing is 2000 cycles and 20 K USD to replace. If those numbers are true the total operating costs for an electric airplane at a busy school will be very competitive.

    Unlike the EVTOL fantasy land, I think there is a future for conventional airplanes powered by electric motors fed from a battery for some applications. I almost certainly won’t ever be buying an electric airplane for myself, but it is probable that I will be instructing in one in the not too distant future.

    • You need to watch Paul Bertorelli’s excellent video analysis of the Pipistrel Velis electro done a year and a half ago, David:

      youtube.com/watch?v=QiNtLBLveeM

    • David, one aspect of convincing a flight school or FBO to install charging systems is the long-term prospect of not having to fool with Avgas or Kerosene any more. Maintaining charging stations or swapping batteries has to be much more attractive than the constant process of ordering, delivery, storage and dispensing of highly flammable liquid fuels. The problem there is that one would have to do both for the time until the fleet changes, which could be a long time.

  21. “According to the report from Allied Market Research, the electric aircraft industry generated $8.5 billion worldwide in 2021, and is anticipated to reach $23.5 billion by 2031, with a compound annual growth rate of 10.9 percent from 2022 to 2031.” (From an article seen in Flying mag).

    Sorry, boys … I don’t believe these numbers. And I’d like to know from whence they came.

  22. In spite of all the teeth-gnashing going on here, I get the impression that most of us would willingly switch to an electric powered aircraft IF (and that’s a really big if) the power storage device (batteries, or whatever) could give us a good approximation of what we currently have. Electric powered airplanes have so many advantages in terms of low emissions and minimal maintenance compared with the current Lycoming or Continental fuel burners. Electric flight will come, but gradually, and basic flight instruction will likely be the first step. As for large kerosene burners, I would more likely bet on the scale up of sustainable fuels with a low carbon footprint long before electric flight. Governments like to impose goals or deadlines to motivate people (or force them, depending on your viewpoint) to prepare for and make big changes. How real those deadlines might be is debatable. However, for those of us of a certain age (including me), a timeline into the 2040s is beyond our probable lifespan, so convincing us to change is a tough sell. The ultimate future of general aviation is probably electric, but it will be up to our children and grandchildren to make it happen.

  23. I’d consider an electric if it had at least the same range and speed and useful load at the same or better price than a proper ICE engine powered aircraft. Not likely to occur in my lifetime, if ever,

    Its a shame too.

    Electric would probably (not proven yet but probably) be easier/cheaper to maintain, and perhaps have lower operational cost as well. A little less noise (most noise is from the prop) would be a nice bonus. I don’t give a rat’s arse about CO2 so that’s not a concern for me one way or the other.

    In any event I’m sure God willing I’ll continue to fly the Maule and the Bonanza until I’m too old to enjoy either.

  24. To add to my prior posts:

    It would need to be recharged as fast as an airplane can be refueled, and recharging would have to be as prevalent as fuel pumps are now. They would also need to solve the problem of batteries bursting into flames unprovoked. Again, not likely.

  25. Well, e-aircraft power sources are still in diapers, no doubt. Give it another 50 to 100 years and electrical flight trainers may break 120 minute flight time durations. Where’s Nikola when you need him?

    e-Agnostic

  26. I don’t think electric aircraft will ever be practical outside of certain specialist use cases, at least not with a radical breakthrough in energy storage.

    But those use cases are quite good ones – e.g. self-launching motor gliders where you don’t need too much energy storage (and it’s a mistake to make ANY glider, motor or pure, that can’t be easily disassembled: that’s what’s really wrong with the Xenos and why I would never have one – even with a gasoline motor, pilots sometimes screw up and have to land in a field)

    Glider tow planes are another excellent use case. I fly the tow plane at my glider club, and it would make things easier and faster not having to baby an O-320 and burn excess fuel to preserve its lifetime – an electric tow plane could get the glider up to 2000′ or 3000′ then simply shut off the power altogether and glide back unpowered to the club airfield with the air brakes out, nose pointed earthwards, reducing cycle time. No worrying about the fragile heat limits of an aircooled Lycoming. Especially paired with swappable battery packs so you can be charging one while towing with the other in a busy glider club.

  27. There’s another ‘gorilla’ in the equation that no one has thus far addressed … the aging pilot population (who mostly possess the financial wherewithal) and the dismal completion rate of student starts. Opposite ends of the proverbial pilot ages. Any time I go to pilot safety meetings or EAA meetings, it looks like they let the people in the nearby senior citizen facility out for the night. These people just want to easily fly at reasonable cost, reasonable range and a modicum of safety. The current changeover to glass panels seems to be their major draw. Like William above (and me), few are gonna be flying long enough to ever invest in any of these electric flying contraptions … and thats what they are … lets stop kidding ourselves. So any company — lets pick Pipistrel, e.g. — that builds an electric airplane that either isn’t significantly cheaper to acquire and/or provides airplane like range performance is doing you know what into the wind … they won’t sell enough of ’em to get economies of scale ergo profit margins. Profit is what makes a company successful. So even if some magic order of magnitude increase in performance in battery technology occurs, unless they can produce reasonable airplanes at a price that makes it pallatable to the pilots of the day … ain’t gonna work. Electric sourced aviaion power has a long uphill road ahead of it. Today, if you want a new 172, you’d have a long wait for it with strings attached.

  28. I gather that all those electric trainers and VTOLs taxis are flying in California and Florida. The battery “expected” range in the electric car I own, fizzles out by 45% when the OAT goes below -5 degrees C. Never mind the actual efficiency while driving. I would be hard pressed to throw in a de-icing system if a designed an aircraft and get my hope for a flight above 9000’. Yes I have hope but in the mean time the battery systems will have to be rethought. Forget lithium. Graphite, lots of graphite is required. 1 kg/1kW power is required for lowly cars. This thing I drive required 56 kg of graphite to build the battery. The only graphite mine in North America is situated in Quebec. Most of them are situated in China. Talk about strategic reserves. In order to supply all cars today with an electrical battery something like 385 new graphite mines will have to be dug down.

  29. “… The one disconcerting vein I see is that, as we run at breakneck speed destroying the ability of this planet to support humans, more people are not willing to take even small steps to slow down the impact on the planet …”

    If this is supposed to be my motivation for hoping for and looking forward to the unicorn of practical EV flight for myself, then count me as an aggressive atheist. And if this is what you truly believe at the core of your being, stop flying now.

  30. I do wonder what the compelling reason for electric airplanes is. Yes, lead is a pollutant and should be eliminated but so are the emissions from coal and gas fired electrical generation plants. Solar plants are only operational 17% of the time and wind is only operational 37% of the time. Alternative energy sources are not a viable option. Our State decided to eliminate coal fired power plants and that is resulting in blackouts this summer as there is not enough power generation capacity. Where is all this electricity going to come from? Carbon dioxide is not a pollutant and does not contribute global warming. So why the move to electric? Here is one reason. If electricity is provided by a central grid then it is controllable by a central authority which can limit and eliminate activities.

    • Hi Dana, you touch on an interesting point, the lead in avgas. The reason we still have lead in the avgas is the same reason we’re not going to see many electric light aircraft, and it has nothing to do with batteries. It’s because the the GA fleet looks like the car population of Cuba: mechanical dinosaurs, long past their design lives and notoriously unreliable, still operating because they are lovingly and intensively maintained – and rarely used. There’s no market for new light aircraft because the private pilot population is declining at about the same rate as the population of aircraft manufactured between 1950 and 1980. (As Larry S noted, EAA meetings look like senior citizen outings.) With no market, there’s no mass production, which means new planes are labor-intensive to build and extraordinarily expensive – which further kills demand.

      If new planes were selling at the rates they did back in the 1970s, we’d all be flying planes certificated for UL94 or something like it and there would be no lead in the fuel. The few remaining dinosaurs, maintained by vintage enthusiasts, would operate at a ~5% power reduction to accept the lower octane. But there are no new planes. And, with no new planes, we’ll see no electric planes either, even if we had the batteries.

      You were a bit off on your figures for solar plants, which produce energy for 28%-35% of the time. However, all the new ones charge large batteries, which allow them to continue to deliver energy into the evening, until demand falls off well after sunset. I don’t know what state you’re in, but the grid problems in Texas were not simply due to renewables not generating; the fallback – fossil plant – capacity didn’t work when it was needed. So, neither worked, and that’s obviously an issue. The limitations of renewables are well understood and are gradually being addressed; what happened to the fossil plants, I don’t know.

      Why move to electric? Because – IF YOU HAVE A WAY TO STORE THE ENERGY – it’s better. Lower maintenance, simpler to operate, much cheaper, reliability of a gas turbine (just think how often we worry about engine failure – and with good reason), ability to redesign the airframe for better performance and much lower noise because the powerplant and the propulsor don’t have to be in the same place. And not dependent on foreign oil (remember, fracking mostly produces natural gas, not oil). That’s a lot of advantages. Energy storage is THE problem, both in terms of feasibility and cost.

      Interesting point about the central authority. Of course, coal-fired powerplants are highly centralized. One of the major trends in renewables is distributed generation, which is the exact opposite: generate your own power, put it in your own batteries (and if your roof isn’t big enough, you team up with the neighbors). The batteries, of course, are still a work in progress, and they’re hard and they may never be good enough to power airliners and we all know it. Small planes, yes, they’ll get good enough for those – but on the trends of recent decades there won’t be any private pilots left by then: when the current crop of EAA Senior Citizens retires, that will be the end of it.

      And, yes, carbon dioxide does contribute to global warming (which is the correct term). Wish it weren’t so, but it does.

      • Global warming contributes to carbon dioxide levels. Basic Ksp values (and history) tell us that.

        As far as cost of electricity being lower than gas, that will only last until they start making EVs pay use taxes like they should.

  31. Good point, Martin.

    Even if the battery energy density problem is solved … there is THIS:

    msn.com/en-us/money/markets/the-wind-and-solar-power-myth-has-finally-been-exposed/ar-AA1aZrIs?

    and even if small nuclear reactors were to come online, the GRID isn’t up to the task either.

    • These comments make me laugh.

      Most people don’t know this, but in New York city in 1900, a third of the vehicles on the streets were electric. They owned the market and people loved them. As gasoline vehicles made inroads, the naysayers said there would never be sufficient infrastructure to fuel the things and carrying flammable fuel around in a tank was insanity.

      Same logic applies to “the grid not being up to the task.” What, you think it’s standing still and will never improve? That’s like sitting on a dune at Kitty Hawk and being sure that infernal flying machine could never actually carry people.

      • Paul,
        As an electrical engineer, pilot and aircraft owner, I see the limits of the battery technology, with no current path to 20x higher capacity batteries.
        A little history;
        The Baker Electric was produced from 1899 to 1915, when it closed, with gasoline cars far exceeded the speed and range. [ Baker was 25 mph max and about 20 mile range].
        Standard Oil in 1870 sold kerosene for home lighting, since distributed electricity did not yet exist.
        They had a ‘waste’ product that was too flammable to use….gasoline, which had no use until Henry Ford developed a low cost car around 1903 and at 1/2 the price of a Baker.
        Prior to both of these, horses provided the city transportation, with TONS of manure daily deposited on the streets [ !!]

        Electric drive systems are now highly developed, in part due to the sophisticated electronics to control the high power motors and battery system. What is lacking, is a battery with the energy density close to what gasoline offers.
        I’ll reiterate the ‘800 lb gorilla’; recharging a very high capacity battery, of about 400-500 kWhr.
        A fast DC charger costs about $125,000, and also requires the local electrical distribution lines to handle a 250kw-350 kw added load.
        I doubt that most GA airports will have the available capacity from the local power authority, and the upgrade costs will be very high.

        So, I wait and see what we get over the next 10 years.!
        Happy flying whatever turns the prop..!!

        • Another thought on how much power that 350 kw is.
          The average home has 100 – 200 amps service at 240 volts, which is 24 -48 kw.
          So, one DC fast charger of 350 kw, is more power than 7-14 homes are rated for.
          The distribution lines in my neighborhood are 12 kv and 20 amps line fuses, so 240 kw. If one of my neighbors installs a DC charger it would blow the line fuses and 100 homes would go dark.
          So, recharging that 400-500 kWhr battery is no small task to install the DC charger.

      • My point was … TODAY’s grid simply cannot handle trying to convert hundreds of millions of cars — or a large % of same — to electric. (See Jim H’s analysis which is realistic). Look what happened in TX last year (admittedly, TX is on its own grid). Simply DECLARING that we will all drive electric cars on a timeline certain is ridiculous without attendant increases in capacity of both generating power AND the means to transmit it AND the means to disseminate it (and maybe, the means to afford it all, too?). There is no long range plan for that part of the logistics trail. Beyond that, the same goes for mining and manufacturing sufficient numbers of batteries, having a plan to dispose/reclaim of them AND build vehicles at a price point where people will want to buy them en masse OVER the ICE we use today, as well. There simply is no long range plans to take Care of the allied issues.

        Like Jim H in CA, I’m not only an engineer, pilot, airplane owner and an A&P, too. Do I think electric power might someday replace the ICE? Sure. Do I see it on any time line that is attainable TODAY … absolutely not. And I see other dangers in the notion of going full electric, as well. It incenses me that otherwise intelligent people can’t see these allied issues … all they’ve been brainwashed into thinking is … “Oh boy … I’m saving the planet with my Tesla!” Well … you ain’t. No today and not any time soon. And airplanes … that’s even more laughable. When all the ‘old’ pilots of today go away … the party is over. It’s time to get real and realize that.

        Do I think electric motors aren’t ultimately better than the gas power… yes. It’s the logistics trail plus batteries that’s the problem.

        To Jim H’s point on DC (type 3) chargers, you should see the gigantic transformers and allied equipment adjacent to the Tesla Supercharging station in Oshkosh. Take a look during Airventure. Email me and I’ll take you there. $125K seems cheap to me.

        • I’m tired of people saying CO2 is gonna destroy the planet. CO2 is 0.04% of the atmosphere or about 400 parts per million. Argon in the atmosphere is three times that of CO2. Because of the slight warming of the atmosphere, plants are able to absorb more CO2 due to longer growing seasons. That means MORE food can be grown to feed the rapidly growing world population. The largest greenhouse gas by volume is water vapor at 0.25% of the atmosphere … SIX TIMES that of CO2. It accounts for 97% of the greenhouse warming of the planet.

          And for this they want to spend tens of trillions of dollars … it’s a ruse.
          Source: NASA

          • The world avoided true extinction coming out of the little ice age, when CO2 levels approached 120 ppm. At that level plants die and with them all other animal life…and us.

            The ‘climate crisis’, is politically pushed from the computer models, which all have predicted much higher temps than those actually recorded. They also do not model clouds at all, with all that water vapor.

            There are some climate scientists that propose that we are extending the current warm period by using hydrocarbon fuels, before the Earth drops into another ice age…which have happened a number of times.

  32. There are some fundamental questions that need to be answered instead of arguing that electric airplanes are ‘good’ or ‘bad’.

    1. Are electric vehicles simpler or more complex than equivalent internal combustion versions? (simpler is better)
    2. Is electricity the future of transportation or do we have an unlimited supply of cheap crude oil?
    3. Are there any specific use cases that can be converted to electric propulsion today, given the state of battery technology, that are better than existing options?

    My answers:
    1. I don’t think anyone can argue with any conviction that an electric car is more complex than a gas-powered one. Same goes for airplanes. No cranks, shafts, carburetors, pumps, valves, fluids, etc. Hands down – electric is simpler, and simpler is more reliable. Anyone who likes the hybrid approach must remember that any hybrid-electric vehicle has all the complexities and failure points of both platforms while still being dependent on fossil fuels.

    2. Electricity IS the future of all transportation. There is no other viable means of reliably powering everything we use, from the kitchen, to the workshop, to our vehicles.

    3. While electric airliners don’t make any sense today, the planes Paul mentions, namely the Pipistrel, are perfect use cases – 1 hr flight time for pilot training, with 1 hr recharge time. There are other great use cases, though. An aircraft that has a 1 hr endurance and can carry, say, 1,500lbs of payload, is perfect for short range cargo transport and agricultural spray application.

    That last one is my target and the reason I started my company, Edison Aerospace (https://edison.aero). Think a fixed-wing plane with a 40′ wingspan and a takeoff weight of about 3,000lbs, 1,600lbs of which is payload. Flown remotely by the same pilots that are spraying our crops today, this is the perfect use case for electric power. This aircraft will cost 50% less to operate than a turbine and 75% less to purchase. As an added bonus – it will reduce the current fatalities among Ag pilots from about 10 pilots per year to zero. With 200 gallons on board, actual flight times will be around 15 – 20 minutes before landing and loading spray media and topping off the battery from a ground control station.

    Here is a video of the setup that I am building: https://www.youtube.com/watch?v=1I2XKvIk-0w

    My goal is to replace all AirTractors and Thrush turbines in the US (and Internationally) within 10-15 years. This is a lofty target to hit, but did anyone think 10 years ago that Elon Musk would sell 1.3 million electric, self-driving, cars in 2022? I sure didn’t, but today I drive a Tesla myself.

    The most important thing in considering alternative platforms is to think what specific functions should the platform perform, and at what cost. What do you give up versus what you gain. When I did this analysis around passenger cars, the obvious choice for me was Tesla. And – yes – I’ve taken 2,400 mile road trips in it already. It takes longer to fuel it up than a gas car, but you can’t beat the car driving itself down the freeway at 80mph, which is how I covered about 2,000 of those miles.

    My goal is to make electric airplanes the same obvious choice for commercial Ag aviation operations. I didn’t buy my Tesla because I wanted to help the environment, I bought it because I knew it was cheaper (total cost of ownership), safer, faster, more reliable, and overall ‘better’ than any other car out there. That is the sort of choice I want to present with my electric aircraft. I think that is a reality today, with the current state of battery technology.

    Thanks, Paul, for another great article!

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