We should just bury the idea of replacing ground cars with their flying counterparts. Not that it is a bad idea to develop electric VTOL vehicle, on the contrary, but ultimately they are going to replace the existing flying fleet: helicopters and planes.
Moving people around cities is much more safe and efficient using trains, buses, taxis and bicycles. Moving people a bit less wouldn't hurt too, with more vertical development, more remote-working, next-door delivery and mixed-use zoning.
I think you're neglecting to think about moving people around in rural and or remote areas. Where I grew up (eastern NC) the ability to travel as-the-crow-flies would massively cut down on time to get places, many roads take 30-45 miles of driving to go what might be 15 miles in the air.
In that kind of area, there's not the population density to support any kind of mass transit (or even really taxis) and the distances are too far for biking to be practical. Readily available electric VTOL would revolutionize rural America. Not much to worry about in terms of air congestion, either.
Indeed, Alaska has this problem and worse. The region relies heavily on seaplanes and short-take-off-and-landing aircraft for logistics. These eVTOL aircraft would be great in Alaska and especially in places without lakes. Places without a lot of flat area for landing, places like Papua New Guinea, have no good options at all right now, so these VTOL aircraft will be transformative.
It’s not that difficult to learn how to fly a helicopter, you only need 20h with instructor before the first solo flight. While that’s just the beginning it shows getting the basic controls down is not the problem. Thus, these VTOL aircraft are only going to be game changers if they are vastly cheaper, which seems unlikely.
The real issue is unit sales being so low. The R22 is a popular and ‘cheap’ helicopter ranking #8 in total sales, but it’s sold less than 5,000 units worldwide over 40 years.
PS: Fixed wing aircraft are popular because they have a huge range of inherent advantages. VTOL sounds great, but the downsides are enormous.
VTOL share most of those advantages of winged aircraft. The reason eVTOL may well be cheaper is that they have a lot fewer moving parts than a helicopter (and much lower vibration, plus using cheaper, lower-maintenance electric motors instead of turbine engines) and much less (and cheaper) fuel. But it'll take good designs. The Lilium one seems non-optimal compared to the Heaviside.
And don't rule out eSTOL. I think we'll see more of that.
Helicopters have an operating cost per hour an order of magnitude higher than a comparable payload conventional aircraft. The purchase price per payload capacity is also nearly an order of magnitude different. It's not the operator cost that determines the difference in price between helicopters and CTOL.
Helicopters are VTOL, I don’t know what you think it means but it’s just ‘Vertical Take-Off and Landing”. https://en.m.wikipedia.org/wiki/VTOL “This classification can include a variety of types of aircraft including fixed-wing aircraft as well as helicopters and other aircraft with powered rotors, such as cyclogyros/cyclocopters and tiltrotors.”
Similarly, an electric helicopter would qualify as eVTOL. People generally aim for something more efficient in flight, but that’s a separate question.
It's hard to claim they're cheaper when they have a fraction of the range of gas helicopters. It's apples to oranges, the flying cars now are equivalent to electric golf carts in performance.
But they last forever. For instance, there are still lots of single engine Piper Cubs (popular in Alaska for STOL capability) from the 1940s maintained, in use, and for sale:
You're right, they last forever, and so the market for new aircraft is tiny. Really a vicious circle: high costs lead to low volume leads to high costs.
I guess the article is actually about taxis specifically, but if the technology exists, they could definitely be sold as personal vehicles for travel along paths that are very long by road, but very short by air. Making rural less... rural, if that makes sense.
The market is probably there if someone could pull off a 1-2 seat VTOL that had maybe a 60 mile range.
I can't see such a vehicle being any cheaper or requiring fewer licences to operate than a helicopter. And helicopters are already available if travelling 20-30 miles in a straight line is a problem you need to fix.
Helicopters are much harder to fly than any of the flying cars in development. To become licensed for one, you're looking at spending around $20,000 in instruction and flying time. That's why so many helo pilots are ex military. Flying cars also put more emphasis on the noise reduction. Both of these priorities give them greatly reduced performance (speed and range) relative to conventional helicopters.
A helicopter is enormously complex mechanically, hard to operate, and either failure prone (piston engine) or expensive (turbine).
Sure an electric VTOL could be cheaper to operate.
You may be right, but I don't foresee the pilot being allowed to control the vehicle. I imagine governments creating laws before long that would require all drone type cars to use GPS, take off and land from designated areas and would not permit manual control unless you meet some criteria.
In which case unfortunately, again, I can only imagine it would be 100x easier to just automate a helicopter rather than make a "flying car"(whatever that means) and then automate it.
One imagines a similar middlebrow dismissal lobbed at those flying camera drones that started selling for personal use about ten or fifteen years ago... We already had UAVs; why would anyone think multiple tiny electric rotors were better?
I don’t know about the legal or other regulatory logistics cost of operating a helicopter, but the physical maintenance requirements for helicopters are likely far far higher than a potential electric vtol vehicle.
Why? Imagine a vehicle that in practicality performs the exact same job as a helicopter, has the same or actually worse failure modes than helicopters(helicopters can at least autorotate, most proposed "flying cars" can neither glide nor autorotate) and now tell me why would such a vehicle have any lower maintenance requirements? Sure it might use an electric motor instead of an engine, but surely safety would require the exact same maintenance regimen as an actual helicopter. This is not going to be a car that you can bring for an inspection once per year, pay £30, change some oil, cabin air filter and be done. It's going to be as costly as any other air-worthy machine to own, in which case any kind of comparisons to a personal car are frankly out of the window, and anyone who thinks they could build a business around one could build a business right now using existing machines. That's not to say that innovation shouldn't happen, quite the contrary - but the whole talk of "flying cars" for your Joe Shmoe is just a pipe dream.
Just getting rid of metal structural components would be a huge boost, that's why the Cabri G2 has zero life limited parts while the R22 has... many. The state of civil rotorcraft is analogous to that of commercial jets 25 years ago. All metal parts, little to no computerization. This isn't inherent to flying cars vs. conventional helicopter configurations, just due to the extremely risk-averse nature of the rotary-wing industry. Helicopters today are very under-optimized but still work pretty well. Think of how shitty old cars were in mileage and maintenance, but still got the job done, while new cars typically last over 100,000 miles.
Just to be clear, the VTOL in this article appears to be a light-sport aircraft (LSA) with a canard wing configuration. I assume it can glide like a normal LSA, though I won't swear to it. It is not an oversized quad-copter.
That said, if it is an LSA, at least in the US, it would have to meet the normal LSA or E-LSA regulations. Including the service schedule, which is less onerous and non-LSA general aviation, but still far more than a car.
They are mechanically simpler, but aerodynamically and electrically vastly more complex. These designs are only possibly due to modern engineering, otherwise they would have been invented before the helicopter.
The flying car designs I've seen have no true redundancies. They look like they would be dangerously unstable if they tried to run on fewer than all motors.
The Volocopter has 18 rotors (fixed, electric motor, with 1 degree of freedom - doesn’t get much simpler) attached to 9 battery packs, and at least 4 can fail (even more when they are “nicely” distributed) and it's still controllable and landable. And they could still throw in a ballistic rescue parachute.
Unless of course the power supply fails, in which case we're back to the point I brought up earlier - you have neither autorotation nor gliding to fall back on, the vehicle just falls out of the sky like a brick - the parachute would help but I'm not sure how feasible that is.
That’s a really interesting observation. Especially when it seems like all the automakers designs on selling subscriptions to an electric car on-demand fleet seems nonsensical for rural areas.
I mean, does anyone actually think flying vehicles will ever seriously replace ground transport? Flying will always be more expensive energy-wise than rolling along the ground; it will always have more dangerous failure modes; it will always require larger and more complex machinery, and it will always be more vulnerable to weather. I don't see any of this changing 5, 50 or 500 years in the future.
I'm with you in that I seriously doubt the idea can be made practical anytime soon. However, I don't think it's fundamentally flawed.
If the trip is much shorter in the air, it may bring the energy consumption closer to ground travel, but even then if we're talking electric energy, renewables are set to make that so cheap it doesn't matter compared to other factors like convenience (it's already that cheap, and dropping every year.)
Commercial air travel is far safer than most forms of ground transport , so it's at least possible that personal air transport could one day be safer than driving.
The big thing really is the advancements in materials science and energy storage density. I don't think we're there yet. But in the next 50 years, very likely in my opinion.
The one thing that may not be fixable is the noise. But this is primarily important for rural living. Air taxis could pick you up and drop you at the subway station outside the city, where the nose won't be that big of a concern.
This is correct. I find this excerpt sobering when looking at stats for private planes.
"""
Doing the math
In other words, take these comparisons with a grain of salt: In 2013, traffic accidents killed 32,719 people, according to the National Highway Traffic Safety Administration (NHTSA). The fatality rate was 1.1 deaths per 100 million vehicle-miles traveled. Assuming an average vehicle speed of 50 miles per hour (a big assumption), the fatality rate for automobiles translates to 1.1 per every 2 million hours.
Taking the preliminary 2013 fatality rate in general aviation of 1.05 fatalities for every 100,000 hours of flight time and scaling it up to 2 million hours gives a comparison rate of 21 general aviation fatalities per every 2 million hours. This suggests that stepping on a private plane is about 19 times more dangerous than getting into the family sedan.
"""
renewable energy sources combined with electrically driven transportation never meant we would do less travel or use less energy over all. it means what all break through events in power generation and efficiency meant, more of it for more uses and more people.
clean easily obtainable energy is going to lead to an explosion travel and who knows what forms it will take
That would be true if cities didn't adapt to the capabilities of ubiquitous flying vehicles.
Cities that can go vertical rather than horizontal has tons of benefits. It means less environmental impact, less distance for people to travel, more efficient energy usage, and probably a ton more.
Imagine New York City with landing pads not just on every rooftop, but every few stories spiraling around the outside of the building. People could live without ever needing to travel to the ground level.
> Cities that can go vertical rather than horizontal has tons of benefits
While it's a popular image in near-future scifi that doesn't look too costly at details, flying taxis with any current VTOL technology don't plausibly enable this, AFAIK, because while they can fly over cities easily, close proximity to solid vertical surfaces substantially disrupts the stability and effectiveness of VTOL systems.
That's why helipads tend to be either on top of or a distance from buildings now; even with a smaller number of VTOL aircraft, pads aren't at those places because it's the most convenient place for them, but because it's the only safe place.
I think that has less to do with strange aerodynamics and more to do with the deadly whirling blades interacting poorly with the solid vertical surfaces if there happens to be, say, a gust of wind. A ducted-fan based system would be much safer, and could work in a constrained urban environment.
Since we're imagining things, how about a network of skybridges between the skyscrapers, perhaps combined with elevator-like automated people movers? To me, that sounds more viable than flying cars in a dense city.
Curious to know about the environmental impact. Does anything that fly spend more fuel to stay above ground compared to an object that rolls on the ground? Will it cause more global warming if successful and adopted widely?
I'm not sure why autonomous cars won't solve traffic someday.
Traffic causing problems like people blocking intersections, not moving when the light is green, or improperly merging, won't happen anymore.
Cars will be able to talk to each other and set up optimal routes. They'll be able to more efficiently match up users with carpools. I'm sure you can imagine more.
These things won't happen for a long time and definitely not with the first generation of truly autonomous cars. Once every car on the road is self driving though? Things will definitely change.
While autonomous cars might be able to reduce traffic, they cannot eliminate it entirely. There is a limit on the number of cars which can drive down a road in a certain amount of time. If more cars wish to use the road than capacity allows, then there will be traffic.
That can only be solved by increasing capacity, either with more lanes or more roads in the same direction, but this is typically not feasible.
The thing that sinks most of these flying car or flying taxi initiatives is the noise problem. Because airplane engines are so darn loud, all flying cars are forced to operate away from built up areas whether or not they're capable of vertical takeoffs and landings. Which makes them inherently redundant, as you're already having to drive out of the city to get to your flying car - at which point you could just drive slightly further to an airport and get on a conventional plane that boats vastly higher cruising speeds and fuel efficiencies.
If not for the fact that airplanes are noisier than a fox stuck in a trashcan rolling down hill, we'd already have flying taxis of a variety of different forms that take off and land on top of sky scrapers. The youtuber mustard did a recent video exploring one such concept:
Using ducted fans and an electric motor both reduce noise, so time will tell if we've finally achieved a "city acceptable noise level" out of one of these designs at long last.
FWIW, most (if not all) of the big tech companies working on flying cars or UAV are aware of the noise problem and have in-house teams working with research labs & consultant on the problem. Now whether or not they succeed is another issue because it's a hard problem.
There is at least one prominent tech firm that appears to think they can mitigate these issues in a year or so, which is... unrealistic.
Anybody familiar with how the military creates stealth choppers that aren't as noisy? I'm assuming it has to do with blade design, but would these changes be applicable at smaller scale and would it be enough of a sound reduction?
The most promising theory is that the "stealth hawk" used actuated micro flaps on its blades' trailing edges to reduce noise and vibrations. I would put money on this being true. Flapped blades have been studied in academia for over a decade, it's definitely an engineering problem now and has clear benefits.
There's no such thing as "stealth" really, but they can optimize blade shape for noise reduction and put mufflers on engines. Those measures reduce aircraft performance (no free lunch in aviation).
From what I heard 3rd/4th hand/speculation, the "stealth" helicopters are quieter than normal helos but at the cost of efficiency and maneuverability. There are always tradeoffs.
Some first order guesses:
-Have lots of blades on the same rotor so the assembly can turn slower
-Put the tail rotor inside a shroud
-Having a smaller rotor might help, since the spread in air speed across the length will have less variation (less sure if this would help)
-Turbine engines can be pretty loud, I'm guessing the same is true of other powertrain components. Maybe put the loudest stuff on the roof.
Kitty Hawk, Larry Page's pet-project flying car company, claims to be working on the noise problem:
"The lack of noise while in flight is another thing Kitty Hawk is highlighting about its new aircraft. In a video posted on its site, Kitty Hawk notes that a helicopter hovering at 1,500 feet emits about 80 dBA, while Heaviside only puts out 38 dBA."
Heaviside is impressive. One of the most elegant eVTOL aircraft I've seen so far. Looks efficient, taking a lot of cues from sailplanes instead of just slapping together a quadcopter with some wing surfaces (or slapping some clunky lifting pods onto an airplane).
I think it's a feasible design. Hopefully they actually start flying it crewed and scale it up to at least 4 seats. If they can execute, I can believe it'd be significantly cheaper to operate than a helicopter.
The lack of safe landing sites also sinks the flying car initiatives. Only a few skyscrapers have helipads today. Adding them after construction is tremendously expensive. Roofs aren't designed to support the weight and are full of equipment (antennas, HVAC).
A Surefly Octocopter is 1850 pounds; what does a large HVAC unit weigh? Surely a roof that's strong enough to support large HVAC units is strong enough to hold an Octocopter.
The one thing I keep thinking about is turbulence...
Generally, small airplanes are moved around a lot more by wind gusts - which means some people get really motion sick in smaller airplanes. That could be quite a shock for people who are used to bigger airplanes.
Does anyone know how these really small multi-rotor air taxis are with turbulence?
I think there's a point to them, but honestly CTOL electric "thin haul" is more important. There are all these regional/rural airports that are under-utilized. It will be hard for electric aircraft to break into the jumbo jet market for the next couple decades. But conventional take-off, extremely high aspect ratio wing electric vehicles could efficiently and cheaply transport a dozen or more passengers at hundreds of miles per hour at distances of between 50 and 500 miles (a range usually serviced by turboprop planes, which are less efficient and no faster than electric planes) without requiring new chemistries or extreme architectural approaches.
I hope someone takes up the challenge. We've got Eviation's Alice, but most of the other players are focused on these eVTOL aircraft or hybridized jets (the hybrid part is a big challenge in itself and offers only modest efficiency advantages).
It may have been an exaggeration on my friend's part. I've never actually taken the helicopter but he has. Maybe the rate changes based on how in demand it is?
I’ve been thinking about this recently. Would it be fair to say that the engine is the single most expensive part of a combustion-powered aircraft, and that batteries are the single most expensive part of a battery powered aircraft?
If so, I expect this sort of aircraft to become quite viable quite soon; if not, then I would be surprised.
Certification is the single most expensive part of an aircraft.
The more "off-nominal" an aircraft is, the harder, and thus more expensive, it is to certify. Commercial aircraft (which a "flying taxi" would be) are also much more expensive to certify than general aviation aircraft.
Drone-style "air taxi" aircraft are very different from a systems, reliability, and redundancy point of view than fixed wing (can glide) or rotary wing (can autorotate) aircraft. The FAA is comfortable with those types of aircraft. Convincing the FAA that single and multiple failures (e.g. battery failure) won't cause a drone-style aircraft to fall out of the sky is going to be very expensive.
As an example, it took many years and multiple attempts to get the FAA to certify composite aircraft. Ref:
Looking at Wikipedia's entry https://en.wikipedia.org/wiki/Powered_lift I don't see any commercially successful aircraft. There are some military aircraft[1], experimental aircraft, and a some unsuccessful commercial aircraft. None is "drone style" yet.
Being the first to type certify a new style of aircraft is very difficult and expensive, which was my point with the list of composite aircraft. Composite aircraft (in my mind) seems much less of a change than powered lift. Maybe ballistic recovery systems[2] will make powered lift certifiable with a reasonable level of effort. The nice thing about BRS is that it is already flight proven and accepted as an emergency recovery system.
[1] The military is willing to take more risks - helps that the jets have ejection seats. The Osprey had 12 hull-loss accidents with a total of 42 fatalities (no ejection seats and it cannot autorotate). Ref: https://en.wikipedia.org/wiki/Bell_Boeing_V-22_Osprey#Accide...
I hadn’t even thought of certification costs, so thank you. How well/badly would that scale with the number of aircraft with the same design? I assume “certify design X for $X” is a separate cost to “certify aircraft Y of model X for $Y”?
Aircraft manufacturers get a "type certificate" for a given type of aircraft which applies to all of the aircraft of that model that are made. The type certificate is expensive but gets amortized over all the aircraft produced.
Changes (depending on how significant they are) can be covered by a "supplemental type certification" which leverages the underlying type certificate and only has to show that the changes are OK.
Supplemental type certificates are much less expensive and is used to certify different models of a given aircraft (e.g. the 737-800 Max is a STC on a STC on a STC ... all the way back to the original 737 Type Cert[1]).
There are also ongoing maintenance monitoring and updates that go into maintaining an aircraft's "airworthiness certificate". The manufacturer must monitor the fleet of aircraft it produces and produce maintenance instructions over the lifetime of the aircraft, including addressing unexpected fatigue and wear issues.
Only in a narrow bill of materials sense (and mostly in the case of jet aircraft). The real expense is in the processes (such as maintenance) that minimize the likelihood of heavy objects falling out of the sky on people and property.
There are also noise issues associated with scaling up personal air transport.
People do routinely fly personal aircraft in sparsely populated areas like much of Alaska. Scaling that up in somewhere like the northeast US or Bay Area seems... unlikely.
I thought of an alternative idea for travel in somewhere like NYC. If you want to cross at certain points of the river, you may need to wait for public transport or use a bridge...
What if we used a combination of drone technology and powerlines...instead of a drone needing to have its own batteries on board, what if there was a power line suspended across the river that it ran along, similar to a street-car. The drone, let's say it holds 2 or 4 people per trip, would basically be a mini flying-on-a-line taxi. It would travel only along the power-line, thus no navigation or control systems needed, no pilot needed.Presumably it could have a much lighter frame due to no battery needed, and you could power it off the rapidly decarbonizing grid.
The downsides I see now are the safety risks if a part flies off, the noise may be intolerable, and you'd need to construct the lines and hold them up somehow. And obviously, you'd need to engineer the product and face the realities of the physics, which I don't know much about.
I wonder what the big secret idea is. Something visually obvious from the fact that they covered it up. An aerospike electric engine maybe? I guess you wouldn't have the same issues you have with cooling such an exit that you have with chemical propellant.
I'm a government researcher working on this exact thing and even I don't really believe it. That said, there is a tremendous amount of interest from commercial entities, which is what drives my work. I'm probably not allowed to name any specific companies, but there are certainly a large number of companies that believe enough to be investing significant amounts of money into the idea.
Sounds like it will probably be a breakout success then. Most things that are wildly successful have "it's not going to work" opposition. Then it's rationalized after the fact when it does.
The fallacy here is “affirming the consequent”: you are taking a principle (which I'll accept for the sake of argument) of if something is to succeed, then it will have had “it won't work” opposition, observing the presence of the fact described in the “then” clause, and concluding that the “if” clause must be true.
But even if the principle is valid, you can only conclude the then clause (conclusion) from the if clause (premise), not the reverse.
While most breakout successes may be mocked as impossible, most things mocked as impossible do not turn out to be breakout successes.
