MAHEPA Flies Hybrid-Electric Panthera


Pipistrel has announced that a hybrid-electric version of its four-seat Panthera has completed the first phase of its flight test campaign as part of Europe’s Modular Approach to Hybrid Electric Propulsion Architecture (MAHEPA) project. According to MAHEPA, the focus of the first flight test phase was powertrain and flight performance. The hybrid-electric Panthera demonstrator has a maximum takeoff weight of 1,315 kg (2,900 pounds), top cruise speed of 177 knots and range of 350 NM.

“In mid-October 2021 the ‘MAHEPA Panthera,’ integrated with the novel, SAF-capable, hybrid-electric powertrain developed during the project, took-off from Cerklje airport, in Slovenia, successfully demonstrating the possibility of local zero-emission flights by performing all-electric take-offs,” Pipistrel said. “Expectations set by prior ground-tests were only confirmed by the powerful, yet quiet performance of the MAHEPA Panthera, which has all the characteristics to become a flying test-bed for future developments in hybrid aviation.”

MAHEPA launched in 2017 with the goal of developing “novel, modular and scalable hybrid-electric powertrains capable of running on alternative fuels or on hydrogen with zero emissions” and is due to wrap up later this week. Project participants include Pipistrel Vertical Solutions, Compact Dynamics, DLR, H2Fly, Politecnico di Milano, TU Delft, the University of Maribor and the University of Ulm. As previously reported by AVweb, MAHEPA also flew its hydrogen-powered HY4 research aircraft for the first time in 2020.

Kate O’Connor works as AVweb's Editor-in-Chief. She is a private pilot, certificated aircraft dispatcher, and graduate of Embry-Riddle Aeronautical University.

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  1. The Panthera is a lovely airplane. Sorry to see this happen to it.

    “Successfully demonstrating the possibility of local zero-emission flights”

    Good to know in Slovenia electricity is made from unicorn farts.

    • Since the solar array in my back yard can charge an EV, may I assume that it is producing unicorn farts?

      I would note that the roof of many a hangar is a better site for a solar array than my backyard. Also, the price of an adequate solar array is probably just a rounding error in the price of a new Panthers.


      • And the reason you paid dearly for those solar panels is that it took huge amounts of “dirty” energy to manufacture them. Then, they may only last 10 years or so barring hailstorms or general deterioration from sun, weather, wind, frost/freeze, rain, thermal cycling, etc.
        Hiding your pollution by exporting it from the site of energy consumption doesn’t make it go away.

        • Ah, so much mis-information.

          1) I don’t know how you define “dearly,” but these panels are on track to pay for them selves in five and one half years, or maybe six. If you were to install solar today, current technology is even cheaper.

          2) While there is some pollution in the manufacturing, it is fairly minor. Certainly way, way less than the manufacturing of a coal burning plant. And operation is infinitely cleaner than operation of the coal plant.

          3) Of course, “they may only last 10 years”. We may be raptured in ten years. Neither is bloody likely. The prediction is that they will degrade one percent per year. Current experience shows less degradation than that. I expect 25 to 30 years easily. Anything past five or six years is pure profit.

          When ever I decide to upgrade, I will just need to replace the panels, the rest of the infrastructure will last well past my lifetime.

          4) I am not hiding my pollution. I well recognize it. It is however, dramatically less than building the coal burner that it replaces. There is a reason that coal burners are being decommissioned at a record rate and no new ones are being built.


    • I live in South Carolina, where our power is mostly nuclear. So around here, that would be “powered by a few ATOMS”. I have solar panels on my house… for my Tesla it’s: “Powered by SUNBEAMS”. Moving to Vermont in a bit, where the power comes from Quebec Hydro. So there it’s “Powered by water falling down a hill”. So my Tesla now, and my airplane someday, are powered by ATOMS, SUNBEAMS, and WATER FALLING DOWN A HILL.

      Oh wait… you seemed to be joking. So what you say as a sarcastic joke is, in reality, is everyday life.

  2. “Local zero-emission flights” … oh, I guess generating the ‘juice’ to charge the batteries being generated elsewhere doesn’t count? OR, maybe it grows on “local” trees? At least in France, 70.6% of their electric power comes from nuclear sources. What a sad story that this isn’t true in the U.S. Here, only 20% of our energy comes from nuclear and 80% from fossil fuels. In California, it’s only 9%.

    At least I’ll give Pipistrel kudos for actually having a flying test article vs. a computer generated pic or video. A refreshing dichotomy from the incessant hollow promises by others.

  3. Glad to see that others are on to the hyperbole of the “Electric Fairy” that manufactures electricity out of thin air! Yes, FRANCE (the country that can’t seem to make a reliable CAR) gets the majority of its electricity from nuclear.

    That isn’t to say there isn’t a place for hybrid power–an engine that provides power to run an electric motor and charge a battery that provides power redundancy in an emergency, or extra power for takeoff and climb.

    • I’d have a helluva lot less problem with a hybrid aircraft design than trying to build a pure electric motor’ed machine running off stored electrical energy. Another cockamamie idea is fueling jet airliners with cooking oil and calling it SAF. What bravo sierra !!!

  4. “Yes, FRANCE (the country that can’t seem to make a reliable CAR) gets the majority of its electricity from nuclear.”

    Quick joke:

    What’s the difference between Heaven and Hell?

    In Heaven the French do the cooking, the British are the police, and the Germans build the cars.

    In Hell the French build the cars, the Germans are the police, and the British do the cooking.

  5. I’ve seen that joke—the earliest mention of it I can find online is 1987– but I’m sure I heard a variation of it in the 70s.

    Added— “The lovers are Greek (or Italian) The bankers are Swiss”

    And like the others, that can be inverted! (Laugh)

    Aviation has more than its share of optimism about “the next big thing”—flying cars, airport runways built on top of freeways, airships, flying boat airliners, the Russian obsession with giant Ground Effect Vehicles, “an airplane in every garage”, Jetson-like city center air taxis, jet packs, one-man personal helicopters, Wankel aircraft engines, and of course “affordable airplanes”…..🤪

  6. It’s a waste of energy, literally and figuratively.

    If we continue to drill aggressively, our fossil fuel reserves remain immense and will last us generations. Furthermore, the US was blessed with great natural resources and can be a world leader in energy production, if only the liberals and their government would either get out of the way or promote drilling and transport and processing.

    All the batteries do is increase weight and reduce range and add to acquisition cost of an already very expensive aircraft.

    Furthermore this whole push for banning fossil fuels is predicated on an artificial agenda.

    I don’t give a rat’s arse about plant food being emitted from my airplane, motorcycles, car, or truck. There is a lot of atmosphere. It can deal with it.

    The day will come, far in the future, where we will run out of fossil fuels, but with wise management that day is not today, or even in the near future.

  7. Q: “How much available engine power do you use in cruise?” A: “All of it”

    Now, being a cheap retired aviator, admittedly my answer is different, but for most folk, the idea is to go fast. The only reason most GA pilots back off by any significant amount from 100% power in cruise is they have engine(s) that cannot be safely operated continuously at full takeoff power.

    This leads me to my question: Exactly what are we trying to accomplish with the hybrid design? OK, it makes some sense in a car, which experiences constant and quite extreme variations in power demand. But we’re talking airplanes here. Does it really pencil out to carry the battery, electric motor, hydrocarbon engine with generator and all the rest simply so we can access a time-limited takeoff (and maybe climb) power boost? What exactly is the advantage of that over just going with our current engines, which can get us off the ground and to altitude with less weight penalty and still be capable of putting it’s max available directly into the prop throughout cruise? I’m not an engineering genius by any means, but intuitively it just doesn’t seem like any efficiency advantages are going to override the penalties being taken on.

    • A similar argument can be made for running lop. Why do you run lop? To burn less fuel. What happens (among many other things) when you run lop? You go slower. What happens when you go slower? It takes longer to get where you want to go. What happens when it takes longer to get to where you want to go? Your bladder and others flying with you start to complain a lot louder.

      I pay a lot to fly faster, why do I want to pay a lot to fly slower. Flying slower means you have to stop sooner, more often which includes more takeoffs and landings which means burning more fuel. So why do I want to pay a whole lot more (all electric, or, hybrid) to go a lot slower and a whole lot shorter distance? None of it makes anything sense to me. Let somebody else think they are saving the world. Not me.

  8. I’m no fan of electric airplanes, but I WOULD be interested in a hybrid to provide redundancy.

    A piston engine can not only provide propulsion, but can charge a battery to drive an electric motor. That motor can be used to provide more thrust for takeoff, OR as backup power in an emergency. It doesn’t take a lot of power once the aircraft is at altitude to sustain altitude or extend the range to find a suitable airport.

    Think of it as “the extra takeoff and climb performance–and extra safety of a twin–without the expense and fuel consumption of two large engines and props–OR the single-engine control issues of a twin.

    As an example–consider an A-36. with a normal 300 hp engine, plus an electric capable of 100 hp. That’s 400 hp for takeoff–what a performer! Lose the engine enroute, and you still have 100 hp “sustainer” (just like a powered glider). It likely won’t take you to your destination, but considering the original Bonanzas had only 185 hp (and THAT was time-limited–165 hp continuous)–100 hp would be equal to 60% power on the original Bonanza, or 35% power on a 285 max continuous hp engine. That may or may not be enough to sustain altitude, but if you are already aloft, that may give you substantially better landing options–even if you only had 30 minutes of extended glide.

    You wouldn’t have the extra drag, weight, and maintenance of the second large piston engine and prop, either–and compared to a Baron on what is essentially the same airplane, wouldn’t have the fuel load, either.

    I’d like to see an engineering evaluation on the concept–it makes MUCH MORE SENSE than a hypothetical battery powered aircraft.

    “Standing by to receive incoming fire!” (laugh)

  9. Well, I see I’m not alone in wondering just exactly what going hybrid in a “typical use” airplane is buying us. Face it, under normal operating conditions (no engine failure) the battery & electric motor part really just gives us some time-limited takeoff power, exactly as was done in the early 185/165 HP Bonanzas Jim cites, but done in a more complex, expensive and inefficient manner. Moreover, that electrical energy has to be replaced from somewhere; either taken from the hydrocarbon engine at cruise, meaning even less speed, or via ground plug-in at destination with all the hassle & time that involves.

    I may be missing something, but to me it’s an exercise whose only point is to show we can do it. And maybe brag about incorporating electricity in the mix, which as everyone knows is always just so green, green, green.

  10. Point is—UNLIKE straight electric, the hybrid provides extra takeoff performance (more fuel efficient than simply installing a bigger engine). It also provides engine-out options without the performance and economic penalties of dragging around an extra engine.

    There is no need to plug in and recharge the batteries between trips—the batteries are recharged and topped off during normal flight—just like the “normal” batteries.

    Problem with the electric “sustainer”? The aircraft could still be flown as a “normal” aircraft—UNLIKE a conventional twin.

    Electric aircraft are far in the future (if indeed the promised “SOMEDAY” ever arrives.) Hybrids can be done TODAY via STC—and in new or older airframes. We can be enjoying the extra performance and redundancy in a relatively short period of time (while most of us are still alive!). And yes, maybe even a little fuel savings!)—“a DIME TODAY vs a DOLLAR in a future that never happens”