With electric aircraft manufacturers struggling against limited battery capacity, aerospace giant Raytheon is at least modestly bullish on emerging hybrid electric technology. On Wednesday, the company announced that its venture arm, RTX Ventures, will pour $12 million into a hybrid startup called VerdeGo Aero. VerdeGo is obtaining additional funding from DiamondStream Partners, Seyer Industries and Standish Spring Investments. Avfuel Technology is also participating.
VerdeGo was founded in 2017 by Eric Bartsch, Erik Lindbergh and Pat Anderson. Bartsch has a background in powertrain systems and Anderson is a longtime engineering faculty member at Embry-Riddle University in Daytona Beach. Lindbergh is the grandson of Charles Lindbergh. VerdeGo’s product line will be hybrid electric powerplants driven by fossil fuels that generate sufficient electrical energy to power the distributed electric propulsion being widely utilized in urban air mobility vehicles and E-VTOLs.
“We think it’s going to take longer for batteries to get to be commercially viable. So we really think many of the successful UAMs will turn to hybrid systems. So what VerdeGo is doing is on the upstream part of electric propulsion,” Pat Anderson told AVweb after the announcement on Wednesday. Specifically, that means marrying an off-the-shelf internal combustion engine to a high-output electrical generator. But there’s a twist. VerdeGo is pursuing so-called blended technology, which means the powerplant is fitted with a device that can continually modulate between full electrical power, a blend of electric and direct mechanical power to a prop or full mechanical delivery. In that sense, the systems are both serial and parallel hybrids, depending on the aircraft requirement. Eventually, the thermal power will come from turboshaft or turbofan engines for outputs in the low megawatt ranges.
The company’s developmental product is called the VH3-185 and uses an SMA 305 diesel to drive the generator for a continuous output of 185 kilowatts. It runs on a blend of Jet A and Sustainable Aviation Fuel. Weight of the system? About 650 pounds, less fuel. Depending on the fuel load, that works out to about 2.3 HP/LB, compared to a few tenths for E-VTOLS that rely entirely on batteries. Key design advantages, said Anderson, are longer range and more burst power, since the hybrid system will also have a battery pack which could be recharged in flight and used when needed. By burning SAF, the company says carbon emissions will be significantly reduced.
Although the SMA 305—and the Continental Aerospace Technologies equivalent, the CD 265, are FAR Part 33 engines—the hybrid setup currently has no clear path to certification. But Anderson says discussions are underway with the FAA to get a cert program established. The company has done about 250 hours of endurance tests in a simulated hover state. It hopes to have a flying prototype by 2025. “We’re not sitting around waiting for fundamental chemistry changes to do this. I’m not trying to minimize what we’re doing. It’s a complex systems integration problem. But I see no showstoppers,” Anderson said.
Hybrid aviation powerplants?
The time spent braking or slowing is very limited – essentially during descents and on approaches to land – not a significant portion of most flight profiles. I’m not sure where the advantage is in terms of energy savings.
This may not be too different from the idea of hybrid oval track race cars (where would their advantage be?) My uneducated presumptions aside, seeing that defense giant Raytheon is involved the real promise in this technology may be limited to a significantly reduced heat signature – an oft-needed trait that could be called upon for limited duration when the aircraft (typically a drone) is being targeted. The DOD may be the only customer able to pay for this technology. I’d love to hear more encouraging thoughts on this development.
I see a major advantage, especially for Single Engined aircraft: If the combustion engine should fail… Battery power can get you to a safe landing somewhere.
That’s why God invented twins 😉
Correction needed IMO:
Raytheon is pandering to climate catastrophists goons like POTUS Biden.
Humans cannot cause runaway climate warming, which is not and cannot happen.
Climate has been warming slowly since the end around 1750AD of a cool era, shown by accurate thermometers like weather balloons and satellite sensors, and by tide gages.
Earth was warmer and climate stable in the Medieval Warm Period when Vikings farmed southwest Greenland.
The effect CO2 can have is small, limited by the ‘saturation’ effect of overlap of spectra of carbon dioxide and dihydrogen monoxide vapour, most of the increase has already been realized.
Read Alex Epstein’s book ‘Fossil Future’ for facts of climate and the benefits of fossil fuels and CO2 to humans.
Curious why you say humans can’t cause climate warming. The Earth has been warming at an increasing rate even since the dawn of the Industrial Age and this has accelerated in the last 30-40 years. From the EPA – “Concentrations of the key greenhouse gases have all increased since the Industrial Revolution due to human activities. Carbon dioxide, methane, and nitrous oxide concentrations are now more abundant in the earth’s atmosphere than any time in the last 800,000 years”.
Not sure why you’d believe a known climate denialist like Epstein who’s clearly a shill for the oil industry over the gov’t experts who’ve studied this subject for decades.
Our rational friend here is always a reliable source of tinfoil hat denialism. I think using the word “rational” is meant to be ironic.
The denialists always love to cite the obviously flawed authors like Epstein when it suits their needs, and dismiss anyone that counters their flawed rationale. Confirmation bias is always well-demonstrated in this forum when it comes to any climate change discussion.
The system described here has its pros and cons, but to make a broad statement about climate change being false and the oft-repeated and always easily-disproved “CO2 saturation effect” is just silly. Can’t wait to see your evidence… Of course the same offenders continue to offend, and never respond to scientific critique.
Thanks as always for the chuckle Rational K., and the rest of the peanut gallery.
Tim, speaking of evidence, what are the black body radiation frequencies from Earth and what is the absorption spectra for CO2? After that, why is warming not occuring first and fastest in the atmosphere (per the AGW theory)?
Real science would investigate why the surface is warming at a faster rate than the atmosphere.
Politics aside, I’ll be sure to check out Epstein’s book. In the short term however (our lifetimes), sustainability and survivability remain worthy aspirations. When the big dogs make claims of having skin in the “green” game, I see the primary focus being an optic of their being in the vanguard, and above all their investor’s confidence. Keep cool this summer!
Our tax dollars at work. My late father, an engineer at Douglas and North American Aviation in the 50s and 60s, introduced me first to the great mechanical cartoons of Rube Goldberg, machines that achieved a relatively simple purpose with an inordinate amount of complexity. Hybrid cars have been a big belly-flop, just like E85 cars and battery cars. It is easy to know when a so-called new technology is likely to fail on economic terms – the developers claim its main benefit is to save the planet, from exactly what, they rarely explain with hard facts. Alas, bureaucrats and politicians that award green grants and much of the media are techno-ignoramuses, math- and history-challenged. At least the people behind this effort admit that pure battery propulsion is DOA. The irony is that the power source here is diesel fuel, what greenies despise most. I wish the developers well, but hope they ask themselves if they’d do this without a cent of taxpayer money, but only their own money? (Most of Textron’s income is from government contracts)
I agree with your statements except hybrid cars.
Ever since the original Prius many of them have been very good. Maybe not so much for the driving experience (Porsches and exotics excepted) but they have proven to be safe reliable and efficient.
Much better for the environment than all electric cars. Less expensive to own and operate, much less damage from mining for battery material, much lighter and more versatile.
I think William’s point is valid. Hybrid cars make sense to people with certain commute activities, especially if they do very little long range trips for whatever reason including aircraft ownership.
I agree that government is putting their thumb on the scale in undesirable ways. There could be value added from some policies like primary research and tax advantages, but writing checks is almost always bad.
Lastly, government needs to be more frugal with the rhetoric and stick with truly consensus science laced with caution about how science is never settled. If Congress could collectively find its courage, I’d love to see bipartisan door slamming on scientists stepping out of their lane. Let’s here science from the experts in their disciplines only, and show them the door when they start pushing policies.
What a ridiculously rational post.
I just gets funnier and funnier.
Now “the smart people” are suggesting to lug a 650 pound apu (not counting Jet A fuel weight) for E-VTOLs?
Roughly twice the weight and half the horespower of a PT6A?
Lighter than batteries. The batteries are the fatal flaw in e-aviation.
“The batteries are the fatal flaw in e-aviation”
Same as it ever was.
I think this project just admitted that out loud and officially.
Roughly twice the weight, but roughly the same horsepower (500hp, running on combined diesel and battery).
No you don’t. You don’t get to count power twice.
That 250hp engine is being used for charging and “bursts of power”, not continuous output!
A PT6A in current singles is putting out between 950-1,200 shaft horespower while the helicopter “C” variant puts out over 1,500 hp.
In fairness, the 950+ variants break your weight limits.
But it is indeed the diesel which is used for continuous output, as well as for charging. It is the batteries which provide the “bursts of power” when needed.
A major advantage of this approach is that the battery packs can be made majorly smaller when they don’t need to support cruise operations.
If the diesel is continuous, then it adds complexity and power losses in the transfer. If the diesel is continuous for main power, it’s not “e-VTOL” at all so why the pretence?
Lycoming won’t do it but this would be an ideal use of a Wankel engine. Wankel was a wanker (Nazi) but the engine is well suited for this application.
Really? 650 lbs plus the motor, prop, fuel and batteries? This technology might have value as a ground-based APU where weight is not an issue, but adding multiple sources of power generation and transmission each of which has significant losses in efficiency and increases in weight, does not make much sense. But we all must notice they are paying their woke/virtue signaling dues by dutifully mentioning the BS sustainable fuel aspect. Follow the money as usual and you will see that it is either tax payer or tax write-off funded. Maybe Biden is right, the rich have simply too much money and must be more heavily taxed so they cannot afford this kind of expensive fantasy.
650 pounds includes the weight of the 250hp electric motor which doubles as a generator. Prop and fuel are generally not included in the weight of an engine.
Right, this does NOT include the primary motor and it’s associated hardware. This 650 pounds is a complex “lump” to replace some of teh batteries.
You can hang a prop off the front of it or use it as a turboshaft. It CAN be a primary motor – it all depends on your aircraft design.
In particular, it could lend itself to eVTOLs which transition to fixed wing flight – being able to initially supply ALL power to electric lift props, then engage the prop, feather the electric props, and spend the majority of the flight running directly off the diesel engine[s].
“and spend the majority of the flight running directly off the diesel engine[s].”
So, it’s a Jet A powered aircraft with added weight and complexity. An engineering marvel. Well done.