These airtaxis are in my opinion just another gimmick. Something in the future, but just around the corner, politicians can point to, which will "solve all traffic problems" thus making public transport investments right now unnecessary or unattractive. Hyperloop, Vegas tunnel, airtaxis. I wonder what will be next. Maybe a monorail?
Like electric cars, electric air taxis aren't for every application, but for specific uses, they have some huge advantages: safer, quieter, more reliable, cheaper to operate, easier to fly. Electric air taxis could open up whole new areas that would've been infeasible before for air ambulance and short commuter flights.
Compare how much more aerial photography and videography we have now with drones compared to when manned helicopters were the only option.
>> safer, quieter, more reliable, cheaper to operate, easier to fly. Electric air taxis could open up whole new areas that would've been infeasible before for air ambulance and short commuter flights
Could be straight from some of those start-ups marketing material. Safety, noise, cost all have to be proofen, right now those are just claims.
> Safety, noise, cost all have to be proofen, right now those are just claims.
True, air taxis don't have decades of real-world use, but the claims are not without basis. Quieter operation has already been verified. Better safety and operating costs are highly likely due to the dramatic reduction in complexity/moving parts (similar to electric cars) and redundancy.
I know a bit about both, helicopters and eVtols. Let's just say that all claims regarding cost, simplicity, redundancy and safety regarding eVtols are just that for now: claims.
Except for politicians and VCs (that each have their very own agenda), airtaxi enthusiasts give me the same vibe as "crypto enthusiasts" (not: the overly sales-y type) - I get and agree that the general, naive value proposition is "great", but it's just not feasible and there's so many lower hanging fruit that could be adressed in the meantime.
And no one seems to address the often brought-up hard questions:
- Look at the (often) questionable security theater at airports and tell me how you'd scale it down to airtaxis?
- The people that for the foreseeable future will be able to afford airtaxis? Celebrities and enterprise C-level persons, not _you_
- Even if "free sky cars that run on zero energy" popped up from nowhere? The average person has a hard time navigating in 2D and can barely leave their hands off their cellphone
Hysterically enough, Berlin's current mayor Kai Wegner (CDU) wants to, again, build a monorail in the city.
This pipedream evergreen is probably inspired as yesterday's modernity fiction accompanying the ideological deconstruction of recently built bike lanes, which may indeed prove euphoric to his senile voter base struggling to recall it as an already tried, and/or failed concept.
Of course, like with the paper reactor, hypoloop and hot air taxi, no politician really gives a shit, if it's a scam or not. It's just the car on a shtick to drag horse and the buggy in aromatic circles towards their post-politics career...
South Korea is really committed to bringing this product to market, they have huge buy-in from the Government and Industry. I did some poking around 4/5 years ago when they started talking about it and the folks I spoke with said it's not just blind ambition, there is a strong will to make it happen. They've made quite a lot of progress, I'm still very skeptical people want to use massive drones to move around, but I think this might end up being one I'm wrong on.
I'm a gyrocopter fan, but their safety record is not fantastic. Among other traits is a significant sensitivity to negative G maneuvers, even mild ones.
Commercial AMEL Instrument rated here. I do hope to get my gyro rating at some point, but the safety statistics are definitely not comparable to fixed wing.
Wouldn’t they be a lot less efficient? This vehicle already does VTOL, and switches to wing flight for cruising, I don’t see how you could beat that.
On safety, the theory doesn’t always match reality, if I recall correctly Gyros are statistically one of the most dangerous recreational aircraft [source needed].
> I’d imagine a small batter pack and motor could even make it vertical takeoff too.
That makes it a helicopter. A gyrocopter has to have an unpowered rotor, which makes it much easier to fly, since there is no reaction force requiring a tail rotor.
Many gyrocopters can clutch the gearbox to the rotor for "jump" takeoff, they ae still classed as gyros because the rotor is unpowered in flight. On the ground the torque is resisted by the wheel brakes.
Probably not as bad as a helicopter? What is probably worse than with a helicopter however is the danger of accidents. The angle of the photo in the press release is weird, but here (https://www.airbus.com/en/innovation/low-carbon-aviation/urb...) the rotors seem to be at about the height of an adult's head.
For a given amount of lift, all things being equal, a single larger diameter propellor will be quieter than several smaller ones at higher speeds, as most of the noise is from turbulence and a function of the difference in velocity between the air accelerated through the rotors and the ‘static’ air surrounding it.
I should have said explicitly, rather the subsuming it in all else being equal, that it’s _very_ different between ‘multicopter’ mode and flying under a wing. The later is, of course, much mor efficient, and the propulsion is correspondingly much quieter.
How much of the noise of a helicopter is from the sonic booms of the rotor tips? I read somewhere it’s a substantial portion but I may be misremembering.
Very little, and rarely, if I understand correctly. The characteristic thwop-thwop noise of many helicopters is from the blade passing through the vortex created by the previous blade. In some circumstances, this might lead to local and intermittent supersonic flow, but it's not typical. I think it also only happens when the vehicle is moving in a particular way, but I don't know how vortices propagate from a rotor blade, so I couldn't say how or when the supersonic flow is most likely to occur.
And airliner engines, the old 737 for example, are even lower. That's why only ground crew approaches the aircraft, and that only after the engines stopped.
Yup, however airliners operate at airports, while this contraption is designed for "urban air mobility", whatever that means. I mean, it has to be something with looser restrictions than heliports, otherwise the niche for this vehicle would be pretty small...
EASA released regulation, and despite whatever companies want you make believe, Airbus being none of those, these aircraft are not allowed to land on a supermarket parking to fly you home. The operate from yet to be defined and built Vertiports (also airports and heliports and pads), for which the basic regulation is there.
Electric engines can be stopped and started quickly and reliably, so they don't need to run while passengers are entered or exiting. This makes the vehicle much quieter and saves battery.
See, Airbus does not have to design from first principle, they can do that from n-th principle. You know, like the difference between clueless amateurs and pros.
As you may have seen, Zipline's new rotors are much quieter due to some ingenious design. I'm not convinced that propellers need to be as loud as they are.
Explain like I’m five: Why do these modern electric helicopters have many small rotors, but traditional helicopters have only one big horizontal rotor? If many small rotors is more efficient, why haven’t non-electric helicopters done it?
Almost certainly because electric motors can be directly coupled to each small rotor. It would be much harder to have individual engines directly mounted to small rotors, requiring additional weight and complexity), and there would be a mechanical complexity and efficiency loss if using a single engine to distribute torque to a number of different rotors through complex gearing and driveshaft mechanisms. Possible probably, but perhaps not lighter or more efficient.
More rotors aren’t more efficient: the more rotor area you have, the more efficient.
Whether you achieve that with 4 small rotors or 1 big rotor is immaterial.
The reason eVTOLs use many small rotors is because an eVTOLs only operate in vertical mode for a short period of takeoff and landing. They aim to be normal fixed wing aircraft for most of the flight!
A helicopter like big rotor would be inefficient- adding weight and drag during forward flight. Helicopters on the other hand, spend the entire flight in vertical mode, for which a big rotor is most efficient.
this stems from newtons second law, but is neglecting second order effects like interference
The modern electric multirotor drones (e.g., quad-, hexa-, octo-copters) are the result of computer controls allowing a configuration that is so unstable that no human could fly it to be actually implemented as aircraft that are much more agile, reliable, robust, and easier to fly (onboard or remotely) than helicopters. They also have a smaller footprint than a helicopter.
Integrating multirotor technology into a fixed-wing aircraft in a VTOL configuration allows for the small takeoff/landing footprint of a helicopter with the flight efficiency of a fixed-wing aircraft.
Not a helicopter, nor an expert in them, but modern electrical engines are significantly more efficient than traditional ICE motors. Also, the scalability of existing small-form quadcopters (etc) means it's much easier for companies to start from the ground up with that sort of tech, rather than developing a complicated rotor/contra rotor set up.
Basically, it would have been very difficult to go the contemporary route in decades gone by, whilst it doesn't quite make as much sense for the usage scenarios to go the traditional route.
My lay understanding is that more rotors are more efficient, but also more unstable due to a concept known as disc loading (the ratio of weight vs swept area of the blades). I'd guess the main reason we don't see more than two rotors on traditional helicopters is partly due to the complexity of transmitting power to multiple locations from a single engine (or having multiple engines), and partly because making such a system responsive enough for stable flight is hard. Electric motors neatly solve both problems.
? Why do these modern electric helicopters have many small rotors, but traditional helicopters have only one big horizontal rotor? If many small rotors is more efficient
so that it can easily maneuver around skyscrappers while beating city traffic and picking their customers
You can rotate them in such a way to use the lifting surfaces (wings) for efficiency during ranged flight while preserving VTOL capabilities. They're more redundant versions of the Osprey.
This looks similar to aircraft from Joby Aviation. I wonder if this will crush their market opportunity now that a much bigger company is playing in the space? How can Joby compete against Airbus?
If there is a market, I am not convinced yet, I think they can. Because one OEM is not enough, there is place for at least a second one. Boeing has nothing, nor does any other major aerospace OEM. Which leaves a slot for Joby, potentially. Maybe someone else, Autoflight maybe. They are Chinese, meaning endless money for the time being, have a decent team and progress steadily and very quietly.
Personally, I'll count out all the other contenders.
Getting an aircraft certified and then scaling up manufacturing is extraordinarily difficult. The most likely exit plan for Joby and other eVTOL start-ups has always been to demonstrate technical viability and then get acquired by Airbus or one of the other big aerospace companies for the IP.
Or automotive, the large aerospace OEMs could do it themselves. Bad news for those start-ups is the push to EVs really heated up by now, automotive OEMs have their hands full.
Those IP acquisitions are tricky so. The IP has to be really advanced and good, say A220 good, and even then the question remains if the price will even close to the total funding those companies got.
Because it’s not a helicopter! It’s a fixed wing aircraft, making it very much not a helicopter.
It would also be reasonable to rename an aircraft class if it was significantly different from other aircraft. For example, an electric, vertical takeoff fixed wing aircraft that doesn’t require a pilot could be reasonably different from airplanes and helicopters to warrant a new name.
It appears to me that they did something clever and the wings and tail section look like they are shaped to generate lift if the vehicle is moving forward fast enough. There are two rotors at the back that blow backward rather than downward.
So possible a vertical take off multi-rotor that can then transition to more efficient (and quieter) plane like operation once up to speed.
Is it clear if it uses the rotors in flight for lift or for forward movement? I think it would be wrong to call it a helicopter if the only time the rotors provided active lift was during take off / landing. There are fighter aircraft which fire thrusters downwards to achieve VTOL, but calling them rockets would be funny.
Apache helicopters have a fixed wing. Granted their primary purpose is arms deployment, but it is shaped like a wing and everything, so it must provide _some_ lift (albeit small).
There's a general fascination with VTOLs in the tech scene for a while, especially as the Next Big Thing for on-demand ride hailing, but I also wouldn't be surprised if part of it is a legal distinction to avoid some of the rules for helicopters to adhere to like Uber calling themselves a limo company instead of a taxi company etc.
Because all those eVTOL start-ups used air taxi as a sales pitch, selling their proposed designes as helicopters woupd have resulted in about 0 funding.
More ways to pointlessly waste energy to benefit a few when there is a climate crisis that demands more energy efficiency, such as via terrestrial mass transportation.
I don't think air taxis in cities will be particularly beneficial to society, but I think the underlying technology will be very beneficial.
It's like the Tesla Roadster. A toy for rich people. But it helped kick-start the EV revolution. Which didn't just give us electric cars, but eventually also electric buses which are just a godsend for cities IMO. (I had an almost auditory whiplash when I visited Taipei because the new electric buses looks like exactly like the old ICE buses, and the ICE buses they have there are SO loud in a city that's already too loud.. and then this EV bus just passes by completely silently.. but I digress.. way too much)
We have a lot of very small airports here in Norway which are underutilized. Sometimes you end up taking a plane to a larger regional airport only to take a 2 hour bus ride to a town.. that has an airport..
Electric aircrafts will unlock the potential of these airports, since the planes will be cheaper to operate and much more silent (the airports could be close to the town center), and I'm quite sure it'll be significantly more energy efficient than traveling to these cities today. Electric planes can be very energy efficient per passenger km. So if a train is not an option they could beat all other modes in efficiency.
Good point, and also kicked off electric semi-trucks and pickup trucks:
> Medium- and heavy-duty vehicles account for less than 5% of the vehicles on the road but produce over 20% of the emissions from the transportation sector, which currently accounts for more than one-third of U.S. green-house gas emissions.
Most of the Amazon Prime trucks in my area (Hillsboro, OR (Portland Metro) are now electric Rivian, and those things are running probably 20+ hours a day.
