The typical electric aircraft company is stuffed with cash on one end (e.g., “Joby Aviation raises $1.6 billion in SPAC merger at $6.6 billion valuation”) while huge promises come out the other end. So far there is little evidence of delivery on the promises that were made years ago, much less on the more recently made promises. Example promise: Joby now says that they’ll be operated eVTOL air taxis in 2024; they tout the fact that they got an air carrier certificate using, apparently, a Cirrus, as evidence that they are progressing toward this goal.
Generally speaking, the electric aircraft folks who showed up to Oshkosh 2022 had the same promises that they were making at Oshkosh 2018, e.g., “we’ll be certified and flying commercially in three years.” It doesn’t seem as though any progress has been made. The batteries are the same as in 2018. The computers and software that enable autonomy and/or idiot-proof human piloting are functionally the same as in 2018. The overall aircraft architectures are the same as in 2018. What these folks are doing with their $billions is a mystery. Let’s keep in mind that the U.S. involvement in World War II spanned the same time period: four years. Admittedly the percentage of GDP devoted to improving aircraft technology was larger, but the changes from 1941 to 1945 were dramatic indeed (B-17 to pressurized B-29, for example; development of the Lockheed P-80 jet fighter).
One area where it seems as though electric-powered aviation has a good chance of near-term success is carrying cargo, e.g., for “last mile” deliveries or going out to islands. What vehicle is already big enough to carry 200 lbs. of cargo and doesn’t need a runway? A single-seat helicopter! These have always been niche products since there aren’t a lot of folks who want to build and fly their own one-seat helicopter that is even trickier to fly than a Robinson R22. But what if the cabin is turned into a cargo compartment and the flying is handed over to a computer with the fast reflexes required to make this kind of machine safe? The folks behind the Mosquito helicopter, in partnership with a Canadian company, are doing just this:
At least for the moment, the heavy lifting will be done by a conventional gasoline-powered engine. Since Oshkosh is more about the human experience of aviation, including building one’s own aircraft, the biggest companies in drone cargo weren’t there, but the event reminded me to check in with Amazon. A June 2022 press release says “We are working with the Federal Aviation Administration (FAA) and local officials in Lockeford [California] to obtain permission to conduct these deliveries and will continue with that collaboration into the future.” So it could happen next week, next year, or next decade!
Readers: What’s your best guess as to when it will be possible to get an aerial Uber in at least 5 U.S. cities? And your best guess as to when it will be possible to get packages delivered by drone to your suburban house in at least 5 U.S. metro areas? Given the technical and regulatory challenges, I’m going to say 2028 for the Ubers and 2026 for the delivery-to-house drones. I think there will be regular drone-based delivery services to at least 5 remote areas of Canada, however, by 2024 (smaller population means it will be easier to get everyone to agree).
Related:
- NASA at Oshkosh (thinking about how to ensure that these autonomous vehicles are airworthy on a continuing basis)
I’m going with never and never. We’ll be lucky if the lights stay on and clean(ish) tap water flows.
Evtol money furnaces will never produce anything remotely close to working.
Aerial Uber, not going to happen unless we get significant improvement in battery technology. Electric cars work well because on the average energy required is low, i.e. around 15 kW to 20 kW per 100 km, this is for an electric car that can transport 4 people. A single person e-VTOL would require around 30 kW/100 km for cruise and another 10kW for the power hungry takeoff and landing (which can also overheat the batteries from the large current draw) for each trip. A simple back of the envelope calculation will show that with current battery technology, electric VTOLs are not feasible. There could be some limited applications for electric fixed wing aircraft that require short flight times (< 45 min) with in the range of a local airport such as flight training.
@Toucan Sam, @Philg What about the diesel engines? Like the Austro AE 300 used by Diamond Aircraft? The DA42, DA50 RG and DA62 look really good on the specification sheet, what do the DA42 owners think of their aircraft?
https://www.diamondaircraft.com
Aerial drone delivery will become common in remote areas by 2025 and will be banned in 2026 when one of these drones has a malfunction and kills the person watching the delivery of a package in their driveway.
Aviation progress in the 1940s and into the 50s and 60s was dramatic, not only because of the funding, but because the technology was climbing up the s-curve at the time, fundamental understandings of aerospace technology were discovered and applied. GA development peaked in the 1970s. The last major development in passenger aircraft was the high bypass turbo fan jet engine, first applied to passenger jet aircraft in the 60s and 70s. Now we are at the top of the s-curve, progress in aerospace will be slow and expensive.
Technology development in all areas, including electronics and computers is slowing down, most of the development today is slow, expensive and incremental. It is madness to believe that technology will always be climbing on an infinite s-curve, all most all of the major technology in use today was developed from the 1870s to the 1970s. It will take major breakthroughs in the fundamental sciences and technology to jump on a fast growth curve again.
@the menace from the north. The problem with the Diesel engines are basically they are too heavy. Diamond Aircraft is really the only company that ever made this work. For a while Cessna was only going to sell a diesel powered 182 but nobody bought them so they moved back to the lycomasarus. The breakthrough will be a very small jet engine or turboprop. Diesel is basically the same thing as jet fuel.
@Toucan Sam
Turboprop engines unfortunately are too thirsty for small a/c. For example, Piper PA-46 (aka M-series) is essentially the same airframe which can have 350 hp Lycoming piston engine (M350) or 500 hp Pratt-Whitney turbine (M500). M350 flies at 213 kt (max cruise), M500 at 260 kt. The other side of that is that M350 has range of 1343 nm (IFR reserve) and takes 120 gal of 100LL, while M500 has range of 1000 nm with 170 gal of Jet-A. The payload with full fuel is 558 lbs for M350 vs 490 lbs for M500.
For most actual GA a/c users additional speed is not that important – but the higher operating costs and reduced range are a big deal.
Jet engines are even less suitable for small a/c. In fact, the current trend in air liner engines is to increase bypass ratio to the point of the engines becoming kinda turboprops with ducted props. The experimental turbofans with open fan are actually more efficient, but require different airframe design, so they’re not common yet. And they do look weird: https://blog.geaviation.com/product/why-the-time-for-open-fan-is-now/
@Toucan Sam, The IO-360 weighs 294 lbs and the AE-300 weighs 410 lbs, a difference of 116 lbs. Does the 116 lbs make such a big difference in a small airplane, given the increases in efficiency and range?
Usually the flying car startups & spaceflight startups come around during the last days of a boom cycle, but now the stonk market is already down 13%, halfway to the bottom of the typical crash, the flying car startups have been around for 10 years, & the boom continues.
This stuff is all vapor ware. Too many edge cases to solve for and battery tech just can’t cut it.
What I don’t get is why Joby isn’t bolting a pt6 to one of their units. Charge a smaller battery pack. Drive motors with that electricity. If these multi engine drone like choppers are not better than current rotorcraft what’s the point of them? Assuming they are – burn some fossils and get some payload and range.
Given existing aviation companies inability to certify evolutionary designs I am not holding my breath on new architecture seeing light of certified day.
Anthony: You raise a good point with the generator idea. Actually it doesn’t need to be even 1/10th as reliable as the PT6. If the batteries hold 10-20 minutes of power, after the generator fails the machine can simply do a normal landing.
These guys https://www.alakai.com/ are trying to build a hydrogen fuel celled evtol. Funny thing is if they get the fuel cell figured out that is worth billions powering all sorts of things and the flying machine, even working perfectly, is comparatively worthless.
Physics is a bitch. Specific energy directly translates into range and payload capability of aircraft. Unless we have a serious break-through in battery tech (10x at least!) the electric a/c will stay thoroughly uncompetitive as passenger transport (specific energy of gasoline is 46 MJ/kg, lithium batteries are at about 1 MJ/kg). Even with electric engines being lighter there’s still no comparison.
These are some “hard hitting” questions to ponder. Sitting here on a Boeing 737-800 on Sunday, September 11th, inbound to Sarasota, FL, I continue to be in awe of the engineering that it takes to deliver 170 people through the air. For the adoption of this type of travel via eVTOL for an aerial Uber, even at a local scale, is 10 years away on my casino scale.
I arrive at the 10 year number due to the fact that Uber level pricing for a small plane is still not a reality. Prior to boarding this Southwest Jet, I looked to charter a Cirrus Vision Jet from KGAI to SRQ, but yet at $16,000 with a necessary stop in North Carolina, the economics are not there for a form of travel that has been around for many years. If Jet Travel is still not available to the masses on an Uber model, I do not expect anything locally to appear in an eVTOL space.
For the second part of the assignment, on my guess for drone delivery, I see that as a five year time horizon. This is a function of the fact that the payload capability and flight time need to increase in order to have a return on investment for the drone delivery.
Why not use large piezoelectrics? In the wings and/or rotor blades, for example, to charge batteries that drive electric motors and supplement the dinosaur-juice-burning engine(s)? Unlike some readers of this blog, I think hybrid vehicles (at least the terrestrial, 2-D world-bound ones) can really work.
Large piezoelectrics in wings? How is that going to work? Second law of thermodynamics says that “You can’t get something from nothing”.
Diamond Aircraft is experimenting with hybrid and electric aircraft.
https://www.diamondaircraft.com/en/service/electric-aircraft/
The thing that amazes me is that these ideas are so enticing that they have grabbed the imagination of investors for well over half a century – people willing to invest year after year after year in a promise that may or may not ever be fulfilled. I don’t know too much about the beginning of the aircraft industry, but I imagine it was much the same. After the Wright Brothers flew there were hundreds of companies that popped up out of nowhere. Some became the manufacturers of today like Boeing, Lockheed/Martin and Northrop/Grumman. Others faded away either because their ideas were unsatisfactory or they were simply money making schemes.
When I think of futuristic aircraft many names come to mind, giants like Clarence “Kelly” Johnson and Burt Rutan. Johnson, an aircraft corporation engineer, was the first team leader of the Lockheed Skunk Works instrumental in the development of the U-2, the SR-71 and F-104 Starfighter, amazing engineering masterpieces. Then there are people who have been luring investors for fifty years and wound up broke and largely discredited like Paul Moller.
I hope it is Burt Rutan that people who attend Oshkosh desire or pretend to be. Moller, much to my chagrin, in my opinion appears to be a pretender, who took investors’ money for over fifty years to ‘almost’ develop a flying car. Do they ever talk about him at Oshkosh as a ‘cautionary tale’?
I’m sure some of the people at Oshkosh are the real deal and aspire to be the next Burt Rutan. I am also sure that others are looking for a big paycheck and will be there just as long as the money flows in their direction. Skepticism is warranted but the idea is still enticing. Also there have been advancements in technologies and materials that make the idea seem more and more possible. Neodymium magnets have allowed the manufacture of extremely powerful and relatively light weight motors. Lithium batteries are great for fantasizing about electric aircraft, but currently lack the energy density necessary for a viable flying vehicle.
I don’t have a good answer to your questions about how long it will take.
> eVTOL air taxis in 2024
I thought assisted suicide was illegal?
If power for takeoff is a problem, how about tethered take-off? Cable delivers power for the first few 100m of altitude gain, and then gets dropped…. Package deliveries would then be by parachute (maybe with active control) to avoid takeoff-landing penalty.