Tecnam Aircraft announced on Tuesday that it has successfully flown its P2010 H3PS hybrid demonstrator aircraft. According to the company, the flight, which took place on Dec. 21, 2021, is the first for a general aviation aircraft with a parallel hybrid configuration. A collaboration between Tecnam, Rotax and Rolls-Royce, the P2010 H3PS is powered by a 104-kW Rotax 915 IS engine coupled with a 30-kW Rolls-Royce electric motor.
“Though H3PS is not intended for market purposes, our successful flight tests demonstrate that [a] hybrid powertrain, with [a] combustion engine coupled with an electric motor, can bear the same useful load of the traditional 180hp combustion engine,” said Tecnam R&D director Fabio Russo.
The H3PS “High Power High Scalability Aircraft Hybrid Powertrain” project was launched in 2018 with the goal of developing a parallel hybrid powertrain suitable for the Tecnam P2010 and “same-category” aircraft that would not affect the payload and overall performance. For H3PS, Tecnam coordinated airframe and system integration, Rotax handled the design and integration of combustion engine and electric motor and Rolls-Royce managed the electric motor and power storage. The project was funded through the European Union Horizon 2020 research and innovation program.
It isn’t clear … are they saying that the weight of the smaller Rotax 915iS plus electric motor and battery pack are the same as a 180hp combustion engine? And nowhere are they saying anything about performance comparisons or a projected side-by-side cost comparison (I get that this is a proof of concept with one flight). I’d have to know more about this. I don’t see how it’s possible but if they pulled it off … GREAT! But one flight and they’re already saving the planet with their creation … give me a break, please. At least there were a few snippets of actual hardware among the computer generated stuff, though.
Rolls-Royce does a better job of explaining the project; go to
on their rolls-royce (not rolls-roycemotorcars) web site. The Rotax always powers the prop, The electric motor mounts behind the engine with a direct drive to crankshaft and has three modes: starting the engine, supplying additional torque for take-off or climbs, and charging the battery pack. The battery pack can be kept small since it only sees intermittent use. The goal is to meet or exceed the same overall payload and performance figures. Be interesting to see how it goes.
This sounds like a trade off. I too would like to see a comparison. If you can cut the engine weight in half or double the Hp with the same weight, then you have an improvement. Or if the the fuel efficiency is doubled without adding weight, then you have something. The best solution is to fly with minimal batteries and the fuel is used to keep the batteries at full charge. An electric motor with a variable pitch prop can aid the efficiency greatly. Otherwise, a fixed pitch is like driving a car with a one speed transmission!
Let’s not forget that the vast majority of electric cars do just fine with one speed transmissions (including direct drive). And drones – both large and small – do fine with fixed pitch props.
A significant benefit of variable pitch props is that they allow constant engine RPM in order to keep the engine in its fairly narrow optimal power band. An electric motor develops full torque at any speed – a constant speed prop just isn’t needed.
>>An electric motor develops full torque at any speed
No, an electric motor develops full torque at zero speed. As speed increases, the torque of an electric motor decreases. It’s not linear, so a good amount of torque is available at most normal operating speeds, but if you unload an electric motor and give it juice, it will develop internal “resistance” of sorts (counter-EMF) as the speed picks up, which means the available output torque is less at the top end.
Fair enough. I was thinking in terms of lower speeds. Thanks for the correction.
Actually an electric motor loses torque as speed increases. If not, it would be capable of infinite power, since power = torque x rpm ! What happens is that a back EMF builds up as rpm increases, opposing the voltage supplying the motor windings. At a certain point enough torque is lost where the load and torque are in equilibrium.
A simple illustration is a battery powered drill. If you overload the drill and slow down the rpm, it over heats and draws more amps (which is like the fuel in a gas tank). Modern drills have higher volts so the batteries last longer per charge. Or, think of letting water out of a water tower. High volts is a small opening and the water travels at high speed. Amps is like a river, very slow but very high volume of current. Multiple electric motors do distribute the volume more efficiently as long as the weight remains low. All electric devices have a sweet spot. Batteries need to remain in that spot.
Gosh, they seem really proud of their low buzz job of the factory.
They must be Seattle Seahawk fans 🙂
I’d like to understand the powertrain layout better. Is the combustion engine connected to the propeller? If so, must the electric motor rotate the unpowered engine in addition to the prop when operating in electric mode?
If you look at the rolls royce website they have both the electric motor and the engine attached to the prop shaft. Think having a really high power starter motor that can be used to add power when needed. According to rolls you can operate the aircraft on either the gas motor, the electric motor or both at the same time. essentially it is compensating for the lower ground level output of the rotax engine without having to build an engine with significantly higher displacement.
If you are going to have a hybrid, aren’t you better off using the battery power on little electric motors across the wings? Then, you fold those up and run on a small turbo diesel at altitude?
Another thought. Couldn’t we get a legal protection for car manufacturers who sell their hybrid components to aircraft manufacturers? Perhaps force a high amount of insurance, which they already have, on the aircraft manufacturer?
I’m not throwing shade at Tecnam for their R&D here. Kudos for experimenting with a combination of solutions. It’s just if you are going that route, it seems to me there are better combos.
the main reason to put the electric motors across the wing is so that you can use a wing optimized for cruse flight. this would normally significantly increase the stall speed however the electric motors along the wings are used to keep the airflow attached at higher angles of attack. The motors along the wing are shutdown in cruise. Nasa is trying this with the X-57 which was supposed to fly in 2017 but has been delayed to this year. The issue I have with this design is that if you have a total power failure you will have to land at a really high speed to keep from stalling. I still haven’t seen what their plan is for that eventuality.
I think a combination of redundancy and BRS is the solution for battery failure.
There’s also great efficiency to be had in a diesel and wing highly optimized for cruise flight in a given range. It might make for unusual performance in climb and decent, but the payoff might be worth it.
Okay, now we have two motors to deal with instead of one. None of this makes any sense except to show that straight battery power in aircraft is just a pipe dream.
So when you use the electric motor only, all frictional losses in the reciprocating engine disappear.? You may have to lock open all the valves also.
After all the verbiage prior to his post, Dale very succinctly says it all !
This is another of those “yeah, that’s nice, but what is the objective we’re working toward?” type of stories.
They say this arrangement allows the aircraft to get off the ground and climb satisfactorily with a smaller combustion engine than would normally be fitted. Then at cruise altitude you can shut down the electric, divert some combustion power to recharge, and toddle along on what’s left. OK, but is toddling along on minimal power really what aircraft users want to do? Won’t they be happier with what we have now, a combustion engine powerful enough to take off & climb satisfactorily that then reallocates that takeoff-climb power to go fast, carrying what was the battery-electric system weight in fuel for range?
Im not saying you are wrong. Presumably, there would be a larger market for lower cost of operation?
At any rate, we know what aircraft users want, and there’s not enough of them to make building airplanes profitable. The market for what the typical owner of today wants is very small and shrinking. The cost of flying in the same old planes gets higher every year. The places to land them get fewer.
Tecnam, and others, realize we need more options. I keep thinking there ought to be engines that bring new tech without switching from internal combustion, but the reality is there really haven’t been any developed that have really won market share (excepting perhaps tiny Rotax engines). At the same time, lots of money and energy is chasing electric and hybrids.
There’s plenty of blame to go around, but the reality is that even nuclear seems more likely than a new fuel burner coming in the next few decades.