Electric R44 Completes First Flight Between Airfields


Tier 1 Engineering announced that it has successfully completed an airport-to-airport flight with its all-electric helicopter design. The aircraft, a modified Robinson R44, flew between California’s Jacqueline Cochran Regional Airport (TRM) and Palm Springs International Airport (PSP) on Saturday. The company is calling the trip “the first helicopter flight between airfields solely by electric power.”

“Progress in the development of all-electric propulsion is similar to other periods of significant advance in aviation,” said Tier 1 Engineering President Glen Dromgoole. “The first aircraft flew short distances, and many people were afraid to ride in the new flying machines. At the start of the Jet Age, there was widespread skepticism about the commercial viability of the turbine engine. Today’s historic flight demonstrates the potential of all-electric rotorcraft and we are thrilled by this achievement.”

Tier 1 Engineering reported that the flight was conducted in collaboration with medical research and development company Lung Biotechnology. The aircraft that flew on Saturday is Tier 1’s third-generation “e-R44,” which the company says was designed to “deliver manufactured organs for transplant” by Lung Biotechnology parent company United Therapeutics. According to Tier 1, the model uses quick-swap battery technology that allows battery packs to be changed in 15 minutes.

Kate O'Connor
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 usual commenters must be too busy enjoying Halloween to make the standard avweb criticisms tonight on this one.

      • I doubted I’d have to look the distance up myself. 😂🤣

        Project appears from the limited info to be a hobby/PR endeavor, but it’s cleverly meeting the stated goal as most every hospital doing organ transplants is bound to be within 21 miles of an airport, and they have helipads.

        Not sure what the carbon ROI will be since they are bound to be putting a lot of work in for a somewhat small application. Still, if they can get 30 to 45 minutes of powered operation, there’s a real market for that.

        • Why do you say there is a real market? This is total redundancy with all the other less complicated? EVTOLs that are being developed that do not have the mechanical complications of a traditional helicopter but can land on the same helipad etc. None of this makes any sense!

  2. Whilst I applaud this demonstration, we all know that the ‘elephant in the room’ is lack of battery capacity. We have long since managed to develop electric motors that are sufficiently powerful and efficient for sustained powered fixed wing and rotary flight, but unless and until we develop much higher capacity batteries then this will simply be a ‘technology demonstrator’. 20 minutes of flight time is simply not enough.

  3. Until there is discovered a technology that can even reasonably compete with the energy density of gasoline or Jet A, this is all so much intellectual onanism, and the engineers know it. It’s equivalent to Woke-ism – posturing to show one’s commitment to solving a problem that does not exist; bending the knee to politicians who wouldn’t know the difference between an engine’s crank and their own.

    This ain’t rocket surgery. A gasoline engine at 15:1 air/fuel ratio (by weight) only needs to carry 1/16 of the weight of the reactants that make power, the rest comes from ambient air, with the exhaust products dumped right back out. Batteries, which have to carry everything required when they take off – and never get any lighter in flight – aren’t within a rifle shot of that kind of energy density and will never be. Until a new technology comes along for energy storage, stop wasting your time.

  4. I see a difference between this project and other evtol/urban mobility projects. This project is taking a proven airframe and electrifying it. There probably already is a market to for helicopters to carry organs. Maybe these helicopters mostly sit around, so a long recharge time is not a problem. They are probably not based at airports, and filling up with gas is inconvenient. Maybe an electric engine will pay for itself in the long run with decreased cost of maintenance. And maybe the short range is not a problem for the places where these helicopters operate.

    Other evtol projects try to do too many things at once: 1. electric 2. multirotor. 3. pilotless. 4. urban mobility. The urban mobility problem is the biggest problem for me. If there was a market for urban mobility, how come it’s not already being filled by R44s or other helicopters? Actually, maybe it is. Some people in New York and Los Angeles fly around in helicopters to go places. But that’s the extent of the market today. Would more people fly in chartered helicopters if it was less expensive? Probably. Not much more though. Too many other barriers to overcome. And where are they going to land to pick me up and drop me off?

    If rich pilot hobbyists have not been able to create a viable electric multirotor to fly around in, then I doubt venture capitalists will be able to. And hobbyists don’t even have to make a profit.

      • The truth is you can’t schedule technical innovation. Your desire for some imagined technology doesn’t mean there’s some amount of finance that can bring it about. For chemical batteries to succeed in aircraft the energy/weight must increase by a factor of roughly 10. All the currency in the world spent on this and I’d bet it fails.

  5. Everyone KNEW building a heavier-than-air self-powered vehicle was impossible. Then, everyone KNEW you could never fly across the Atlantic non-stop. And it would be impossible to fly around the world non-stop. Ok, sure, those were overcome, but we all know it’s impossible to fly humans to the moon and back. Or how about how we knew it would be impossible for a helicopter to fly faster than 250kts?

    Everything is physically impossible until someone proves it’s not. Then it’s obvious it was possible all along.

    This is a tech demonstrator doing exactly what tech demonstratora do: prove something is technically possible. They aren’t supposed to be viable commercial products on their own. They spur refinements to the concept until a viable product is possible. It’s a bit of a chicken vs egg: until it’s shown to be technically possible, the technology for a viable product is never developed.

    • Thank you, Gary B, for saying what seems so incredibly obvious to so many of us (should be all of us, since it was pretty much what the quote that was in the article said!), and still seems to elude all of those who can’t see past the end of the fuel truck hose.

      • Forty-five years ago Bryan Allen flew a human powered airplane across the English Channel. So where are all the human powered airplanes these days. Demonstrating something is really nothing compared with perfecting it and they are at least a long way from that!

        • As a pilot and endurance cyclist I would love to give one a try but have yet to find a pedal plane at the local GA Rent-A-Center.

    • Electrochemical energy storage has very well known and finite physical limits. Lithium, one of the most active metals on the periodic chart is king when it comes to moving ions. There won’t be anything better anytime soon. There is a reason the hundreds of billions of dollars put into battery research yields no results. We understand the physics behind modern rechargeable batteries exceptionally well. Remember, common hydrocarbon fuels contain the same energy they always did. We were never able to make a gasoline that contained twice the energy, despite claims in the 1930’s that we were able to do so. What we did instead was to vastly improve engine efficiency. We don’t have that option with 93-95% efficient electric motors.

    • I await the day that these very same nay-sayers harrumph and hyper-parse their arguments to admit that they lacked the imagination to see that if electric rotorcraft can fill a market niche, they will be developed. After filling that niche, they will be further developed to compete in existing aircraft markets on price, convenience, noise, cleanliness, meeting the inevitable eco-restrictions, or whatever the future may bring.

      I applaud Tier 1 Engineering for their accomplishment, but I saw a single-place electric helicopter at the Composite-FX factory in Florida last Spring and at their booth at Airventure. If that low-budget/high-talent outfit can make a kit-built electric Mosquito experimental helicopter kit out of essentially off-the-shelf components, it won’t be long before commercially viable electric rotorcraft are commonplace.

      In my computer career, an apparently difficult problem was denoted a SMOP: Simple Matter of Programming. This is a SMOE.

    • Two thumbs up for your comment. The first electric cars could barely make 40 miles, now GMC just released an electric truck with a 400 mile range. That said, while electric versions of traditional helicopters will no doubt enter the markets in the future, I think the more modern drone-based designs with high prop redundancy will be the EVTOLs of the future.

      • Not a relevant comparison.

        For a commuter car like a Tesla immense weight is largely irrelevant.

        Significant gains in battery energy density are impossible so a commuter car can largely ignore its weight as it adds more and more heavy batteries to get more range.

        An aircraft is not afforded this luxury.

        Also check on the forums. Teslas don’t often get the mileage advertised. Hot, cold, hills, heater use, AC use, dormant time, terrain, winds, etc. all adversely affect the range. A ‘400 mile’ Tesla is realistically a 300 mile commuter, with reserve.

      • There is a saying in the AC industry, never buy the A model of anything, including a full sized Ford or GM electric pickup. I want to go hunting or fishing up in the Sierras and pull my small trailer. It is a 5 hour drive from the coast and up 9000 feet in elevation. Even if I could get there, where are the charging stations in places like Florence lake or Jackass meadows. If you believe the range hype being promoted by Ford and GM, call me about some beach front property in Nevada.

  6. Thank you Chris C.

    I double majored in physiology and physics at Rutgers.

    The periodic table is a cruel mistress. There are only so many choices that could be made for electrochemical potential difference. The is no miracle technology yet to be discovered, only fine tuning of what already exists.

    The graph of battery ability vs. research expenditure has reached an asymptote.

    • The problem becomes not technology, but COSTS increases exponentially the closer you try to approach the asymptote. Just because battery power density can be improved does not mean they will be cheap/available enough for realistic general use.

  7. It’s encouraging to see so many comments from the aviation community that are sober minded and balanced. So many are rushing headlong into the battery world and make rash comments about EV’s. Since the energy density of rechargeable Li-Ion batteries is 2.1 MJ/L vs. 36 MJ/L for gas it is clear at this time, battery powered vehicles cannot match the overall capability of ICE’s. Our Arrow can travel about 500 miles in any direction carrying about 500 lbs. of fuel. Batteries approximating that ability would weight far more than the aircraft itself. No one can argue that. Gas packs an energy wallop that overcomes less efficient IC motors. Even while powering efficient electric motors, batteries cannot match that and also have a host of other limitations that are well known, susceptible to temp extremes, parasitic drain et. al. The research is encouraging, but I see too many attempting to force electric vehicles before they are ready for prime time. Even for instruction … what is the time an electric 172 can remain in the air with reserves? One student and back to a charger for a few hours? Opinions are flying all over about causes of climate change. Animal husbandry? ICE’s? Even battery operations beginning with the mining of Lithium from the ABC countries encur a carbon penalty. A respected think tank concluded that given the overall factors in BEV production a 1200 kWH BEV and a compact ICE have about the same carbon footprint. So how much overall advantage would an electric training aircraft have over an ICE? I think none at the moment because they cannot match the endurance of an ICE. Someday, I think EV’s will be the primary players when energy sources match electric motors. But not yet.

  8. Another classic “Solution in search of a problem…..”

    EVs were going to be Jetson-like “intercity commuters”–but lacked the range, payload, and places to land. Then the prediction was for swarms of drones–either carrying passengers, or “something important.” Hasn’t happened…..and has been pointed out a number of times–perhaps best by Chris C, William, and Jeremy H.

    It has also been pointed out that the vehicle (the R-22) has existed for years–yet nobody has seen the need of the service.

    If anyone REALLY BELIEVES this will be a “thing”–they should mortgage the farm and invest in the future–if you are right and the physicists are wrong, you can make a killing! That’s the benefit of the Capitalist system.

  9. These reactions generated by the latest EV announcement always remind me of the old joke about new prisoner Dutch’s first day in the exercise yard. As the prisoners mill around, periodically one will yell out a seemingly random number, followed by laughter from others. On inquiry, it is explained to newbie Dutch that everyone has been “in” so long, all have memorized everyone else’s jokes, so to shorten things up, they have assigned each joke a number.

    If we’re really serious about reducing our carbon footprint through bit transmission reduction, perhaps this could be applied to the limited and well-worn number of reactions to EV’s? “They laughed at Orville & Wilber” could be #4, “Physics preclude batteries ever matching petroleum’s energy density” #7, etc.

    Oh, if by some strange quirk of fate you never heard the prisoner joke, Dutch memorizes some jokes and decides to join in, shouting “Thirteen”, one of the jokes he feels is funniest. No one laughs. Later, his cellmate explains “Well, Dutch, some people just can’t tell a joke.”

    • The next day, he called out “97” and the other prisoners roared with laughter – they hadn’t heard that one yet.

  10. If we are going to talk jokes and fairy tales, perhaps “Chicken Little” would be appropriate for those who actually believe in miracles. Recall that Chicken Little ran about, making unfounded claims that “The sky is falling”–causing others to take action to prevent the falling sky from harming them. In reality, there was no evidence of the “falling sky”–life pretty much continued without worry–the predicted catastrophe never happened.

    To continue the fairy tale analogy, perhaps “The boy that cried wolf” would also be appropriate–the boy reported wolf sightings so often that nobody believed him–until a real wolf actually did appear.

    In more modern times, (dating back to about 1600), there have been countless claims that a “perpetual motion machine” was ALSO “just around the corner”–yet the concept has never worked (though some people actually believe in it.

    The internal combustion engine has only been around for about 100 years–before that, there was steam power–or electric power. Electric power has never worked well for portable power (without connection to a generating source) due to the limitations of batteries–and there has been no “magic battery” produced to provide the mobility of internal combustion. But that doesn’t prevent the ever-hopeful from saying “it COULD happen”–though it hasn’t happened in over 100 years.

    The constant hype of “just around the corner” reminds me of the old “carnival barker”–“step right up, Rube……I’ve got this magic elixer that cures what ails you….” Professor Harold Higgens (from “The Music Man”) also exploited those who WANTED TO BELIEVE in what he was sellling……

  11. You could have saved a lot of time by simply typing:

    #17-f (fairy tail variant)

    [And it was Professor Harold Hill who didn’t know the territory. Henry HiggIns tried to cure the cockney.]

    • Since this whole subject is really a cruel joke, the most appropriate metaphor is about the optimistic child who got a pile of manure for Christmas and ran out with a shovel screaming there has to be a pony in here somewhere. Substitute money and the mythical high density low weight battery.

    • OF COURSE you are correct—I conflated my “HH’s”—(Henry Higgins and Harold Hill)—it was “Professor” Harold Hill that tried to scam the local populace into something that was not true—yet another example of someone trying to convince people that WANT something to be true.

  12. >>designed to “deliver manufactured organs for transplant”<<
    That helicopter is going to be landing on the hospital helipad to make the delivery. Then it is going to be sitting on that pad, blocking it from use by other emergencies, until either the battery pack is recharged or a replacement battery is obtained. Organ transplants don't happen every day, even in transplant hospitals, so the likelihood that spare batteries will be staged at every possible hospital helipad is rather slim. The logistics just don't seem to be all that practical.

  13. As if there is a booming untapped market for battery powered organ delivery.

    As if a police car, ambulance, or conventional aircraft can no longer due this obscure task.

  14. The problem with this whole evtol/urban mobility push is it is being driven by political and social considerations rather than economic and technical considerations.