Monday, May 20, 2024

Post 46: The Jetsons Are Coming

I like speculating about the miracles (or horrors) of the distant future as much as the next guy. After all, who can resist painting a picture of what life will be like in 2050, or 2070, or even 2100? When it comes to my blog posts, however, I generally try to stay grounded in what is real, or at least likely to be real in the next couple of years. During my career I have witnessed predictions of “the next big thing” burst onto the scene only to fade into oblivion just a few years later.

Still, I have gone out on a limb from time to time to tout a technology that is more than a few years away from prime time. Things like autonomous vehicles, virtual/augmented reality, and the combination of artificial intelligence and robotics – all things that get a lot of press but have yet to reach mainstream adoption.

My timing may have been a couple of years off, but I stand by my predictions of those technologies being urban (and societal) game changers. After all, Waymo is providing over 50,000 paid trips per week in its autonomous robotaxis with virtually no serious accidents. Apple, Sony, Meta and many others are selling virtual reality headsets to gamers all over the world to immerse them in fictional but realistic worlds. And augmented reality glasses are being sold by Apple, Microsoft and Magic Leap to businesses who are looking for ways to increase productivity by layering information on top of the real world. And if you don’t think the AI/robotics combination is for real, check out the Amazon fulfillment centers where 750,000 robots are augmenting – and replacing – human workers. Ubiquity is still a ways off for all of these technologies, but their potential should be obvious to just about everyone.

The Archer Midnight eVTOL

This month I’m going out on a limb again to talk about a technology that has a great deal of promise, but which is probably 5 or 6 (or 10) years away from common usage. The technology is known as Electric Vertical Take-Off and Landing aircraft (or eVTOLs). Those who are less technically inclined sometimes refer to them as electric air taxis, because that is likely to be their first commercial use, but the potential goes beyond that to a variety of transportation needs.

Virtually all of the big names in aviation are pouring money into this suddenly trendy business venture including Boeing, Airbus, Embraer and several major airlines. But much of the innovation has come from smaller companies that seem to be pushing harder for actually getting eVTOL aircraft into production. Companies like Archer [1], Joby [2], Lilium [3] and Wisk [4] are currently getting the bulk of the headlines. Click Here to see an eVTOL in action.

The industry is so new that there isn’t even an agreed upon name for this new class of travel. Advanced Air Mobility (AAM) is probably the leading candidate, but Urban Air Mobility (UAM) is frequently used as well. For the moment, this technology is focused on relatively short, intra-urban trips. A few manufacturers with somewhat longer range capabilities, however, refer to the service they can provide as Regional Air Mobility (RAM). The divided terminology reflects an industry with lots of different players, each with their own vision for the service being provided and the aircraft being produced. Over the next few years, I expect there to be a considerable amount of consolidation but innovation in design is likely to continue.

The title of this blog post references the 1960s cartoon in which the family of George and Jane Jetson had a flying car, among a variety of other futuristic household devices. Although eVTOLs could in theory be used for personal transportation, that is not what I’m going to write about here. Flying cars are much further into the future and may never be widely adopted because of costs and safety issues. But an eVTOL-based air taxi service is both technically and financially feasible, assuming that things continue to progress as expected over the next several years.

Distinguishing an eVTOL From a Helicopter

It may seem like an eVTOL is a solution to a problem that has already been solved. After all, traditional helicopters offer vertical take-off and landing, and already function as air taxis in many major cities. There are, however, several differences in basic design that give eVTOLs a distinct advantage in urban settings.

Multiple motors - greater safety. Helicopters typically have one large rotor for lift and propulsion and a much smaller second rotor for stability. In contrast, eVTOLs typically have many motors for both lift and propulsion – generally 6 to 12 motors, but sometimes 20 or more. The advantage of this configuration is that it does away with the single-point-of-failure problem that has plagued helicopter travel. If an eVTOL motor fails, it can continue safely to its destination using the remaining motors. Multiple rotors (generally with half spinning in opposite directions) provide lift to the aircraft that is distributed across the airframe as well as perfectly counterbalanced, so that no tail rotor is required. The stability that is inherent in this design makes it both safer and easier to fly. Easy enough, in fact, that at least two companies (Wisk and eHang) are testing autonomous eVTOLs where the pilot is replaced by computers.

Electric power – less pollution and less noise. Air travel typically comes under attack from environmentalists because of its reliance on fossil fuels. As noted above, the “e” in eVTOL stands for electric which means there is no direct pollution emitted and total pollution should drop over time as the country’s power sources get greener and greener. It does entail the use of batteries for energy storage which have their own environmental issues, but even that is likely to be lessened over time as battery technology improves. More importantly, in my opinion, is that the combination of electric motors and multiple rotors results in noise levels that are 20 to 40 decibels lower than typical helicopters or piston airplanes. An eVTOL flying overhead is likely to be so quiet that it won’t be heard over the background noise of most cities. That low noise profile will make it easier to locate landing facilities, even near residential areas that are noise sensitive, and to operate during noise sensitive portions of the day (such as early mornings).

Fixed wings and tiltable rotors – greater efficiency. Helicopters rely upon the main rotor for lift at all times. The multiple rotors of an eVTOL provide lift for take-off and landing, but generally are designed to tilt forward to provide lateral propulsion to travel from point to point. Most eVTOLs also have a fixed wing to provide lift during the forward travel segment of each trip. This is a more energy efficient arrangement for the majority of the flight – something which is crucial for battery powered aircraft. Even with this added efficiency, eVTOLs have a much shorter range than a helicopter – in the neighborhood of 100 miles – because batteries are much less efficient at storing energy than fossil fuels. While this is a crucial limitation for many use cases, the urban air taxi role typically does not involve long distances which is why that has been the early focus for this technology.

Electric motors – cost savings. Helicopters are typically powered by what is known as a turboshaft engine. Although they are marvelous feats of engineering, they are expensive to buy, expensive to maintain, and expensive to operate. Electric motors, on the other hand, are much cheaper on all three fronts – even if you have eight of them. Consequently, an eVTOL is projected to be roughly two-thirds the cost to buy and operate compared with a similarly sized helicopter. That cost savings makes a huge difference in the cost per passenger mile which means in turn that the potential market for eVTOL-based air taxi service is substantially greater than the current market for helicopter-based service. A current industry goal for eVTOL taxi service from a downtown “vertiport” to the airport is to be able to match the cost of a luxury ride sharing service (e.g. Uber Black).

With all these advantages it might seem as though helicopters are destined for the trash heap. That isn’t likely to happen in the foreseeable future, however, because eVTOLs cannot match the range and payload of gas-powered helicopters. That means that most military uses, search and rescue operations, police patrols and many other use cases are still going to rely upon traditional helicopters. In the near term at least, eVTOLs are likely to focus on the air taxi role and similar short-trip uses such as sightseeing (e.g.tourism flights over the Grand Canyon).


Contrary to the world of the Jetsons, an eVTOL-based air taxi is not going to pick you up at your house. Air taxis will need special take-off and landing facilities similar to the heliports and helipads used by helicopters today. The industry currently refers to these facilities as “vertiports” although the distinction between a vertiport and a heliport is not entirely clear. The FAA has issued some provisional guidelines, but final regulations are still undefined and may be subject to frequent revisions once they are issued simply because the size, weight and re-charging needs differ substantially from manufacturer to manufacturer.

Since air taxis are not going to replicate the anywhere-to-anywhere service that ride sharing companies like Uber provide, it means that vertiports will need to be located where travel demand is high. Airports are an obvious location because they are a high-volume travel destination and because they are already equipped for handling aircraft take-offs and landings.

In fact, trips from a big city downtown to the nearest airport are likely to be the predominant trip type when eVTOL air taxis first start doing business. The appeal of an eVTOL trip will be particularly high in cities where the airport is poorly served by mass transit and traffic congestion makes driving to the airport a time-consuming task. Think of downtown Manhattan to JFK, LaGuardia, or Newark airports. Or downtown Dallas to DFW. Or San Jose to SFO. United Airlines has reportedly signed a $1 Billion deal with Archer Aviation to use their eVTOLs to shuttle passengers to their airport hubs starting with the Chicago Loop area to O’Hare airport. A trip that might otherwise take 45 minutes to an hour in an Uber is likely to be 8 to 10 minutes in an air taxi – assuming, of course, that you are near a vertiport.

Where will people traveling to the airport start their trip? Existing heliports near commercial centers are an obvious option although some of them might not be able to accommodate the modifications that eVTOL traffic might require. Office building rooftops are sometimes used for heliports and supposedly eVTOL companies are actively scouting these potential locations in major cities. Not every building, however, is going to have the necessary structural strength or the ability to dedicate part or all of the top floor to air taxi operations. Parking garages are another possibility since they have a large footprint and the top level is often underutilized. Unfortunately, a parking garage surrounded by tall buildings might have issues with safe approaches and departures, particularly if swirling winds are common.

In short, dense commercial and mixed-use areas will be the prime locations for vertiports but it will not necessarily be easy to find the ideal site.  As air taxi travel becomes more popular, major commercial districts may build their own vertiport just to make sure that their tenants have access to the eVTOL transportation option.

Regional Air Mobility

Although the vast majority of the AAM industry is focused on relatively short trips within a metropolitan area, Lilium is developing an eVTOL aircraft with broader aspirations.  Their product will have a range of at least 150 miles which means that short intercity trips are also a possibility.  Think New York City to Philadelphia, or Washington, D.C. to Baltimore, or San Diego to Los Angeles.  Click Here to see the Lilium prototype in action.

Again, the selling point is the time savings that will come from both higher speeds and the avoidance of congested streets and highways.  Lilium’s website shows a hypothetical trip from New York to Philly that takes half the time of a trip by car or train at a cost that is competitive with both (roughly $200).

Battery technology is improving rapidly so it is not inconceivable that in a few years the range could expand to 200 or even 250 miles.  That would open up a much larger number of urban pairs that could be served by eVTOL aircraft and potentially change the economics of short hop airline flights.


So far, I have painted a pretty rosy picture of the Advanced Air Mobility industry.  The technology is largely proven, the economic potential seems legitimate, and venture capitalists and major aviation companies are jumping into the field with abandon.  What could possibly go wrong?

Well, plenty. [5] To begin with, none of the eVTOL designs have been certified by the FAA for passenger service. Only a handful are actually doing full-scale test flights with their final motor, airframe, and control system designs. Doing computer simulations and remote control mockup flights are fine, but nothing replaces hours and hours of actual flight time with the final product. Most of the manufacturers will give optimistic assessments of where they stand in the certification process, but aviation history is littered with innovative aircraft that got bogged down chasing certification not just for years, but sometimes for decades. The more exotic the product, the greater the chances for delays, and eVTOLs are about as exotic as aircraft come.

Second, the public has to learn to trust this new approach to transportation enough to use it and to allow vertiports to be built in their cities. I rode in a Waymo autonomous taxi and thought it was both safe and exhilarating. But many of my friends said that they would never trust a computer to drive them around. How are people like that going to feel about a battery-powered air taxi that uses tiny motors with tiny propellers to zip around town? And how are the NIMBYs that oppose anything other than single family homes going to react to a vertiport in their neighborhood and eVTOLs flying over their kids’ schools?

Third, this is a technology that seems almost custom made for cost overruns. Sure, you can say that an eVTOL will cost two-thirds as much as a helicopter, but until you are actually selling them at that price it is all just speculation. Any untested technology is likely to encounter problems at some point in the development process and that can lead to both time delays and unexpected expenses. As far as I can tell, no one in the entire AAM industry is in full scale production or even anything close to that. Scaling up from hand-built prototypes to a production line product is both complicated and expensive.

Impact on Cities

Assuming that the AAM industry can overcome these obstacles and get a certified eVTOL into production, how much of an impact is it likely to have on cities? Probably not very much. It is tempting to think back on the Jetson cartoons where everyone had a flying car and conclude that eVTOLs are the solution to automotive congestion on our roads. Or you might be thinking of eVTOLs as “Ubers that fly” and assume that they will be just as commonplace and carry just as many passengers around the city. Both assumptions are wrong and the total impact on the urban transportation mix is likely to be almost unnoticeable for the foreseeable future.

First of all, this type of air taxi service is only going to be financially feasible in big cities where there is a lot of congestion. It is not going to reach mid-sized midwestern cities until the costs come down considerably. I live in midtown Kansas City and typically an Uber ride to the airport costs around $60 and takes about 40 minutes. Those numbers would have to go up considerably for an air taxi service to make sense. For most cities, eVTOLs are going to be an exotic rarity.

Secondly, even in big cities vertiports are not going to be common enough to support a large number of flights. New York City only has three public heliports, and while there are considerably more private helipads, few of them are likely to be interested in or capable of supporting regular air taxi flights for the general public. I’m sure more vertiports will get built but it won’t be a fast process. Without many vertiports accommodating many air taxi flights throughout the day, the trip totals are simply too small to really make any difference.

Thirdly, the cost of an eVTOL may turn out to be just two-thirds the cost of a helicopter, but that still means that the cost will be several million dollars apiece.  Starting an eVTOL-based air taxi service won’t be like buying a used Camry and becoming an Uber driver.  This is an industry that is going to be funded by serious capitalists with deep pockets.  The roll-out is going to be cautious at a few cherry-picked locations until true demand is fully understood and profitability is a reality not just a projection.  This again means that ridership volume will be too low to have an impact on the overall transportation pattern.

Finally, I’m highly skeptical of the estimates that riding an eVTOL to the airport will be about the same cost as a luxury Uber ride and two-thirds the cost of current helicopter air taxis.  The reason I’m skeptical comes down to simple supply and demand.  For at least the first five to ten years, supply is going to be severely constrained by limited eVTOL aircraft and limited vertiport capacity – and limited supply means high prices.  That means this is going to be a transportation option for the affluent or for businessmen with generous expense accounts, which is too small a segment of the population to make any difference in the streets.  Time is money for some people, but most of us will tough it out and slog through traffic.

At some point, eVTOL supply will be unconstrained and vertiports relatively common but even then I’m guessing that the share of total trips made by air taxis will struggle to get over even one- or two-tenths of one percent.  In my opinion, the early adopters are likely to be major corporations replacing the helicopters they currently use for their executives with eVTOLs so they can look “cutting edge” and environmentally conscious.  Air taxi service will pop up in the cities where traffic congestion is the worst and gradually spread to other locations.  

As range increases with improvements to battery technology, short hop service between nearby cities will also become more common.  The big advantage versus traditional aircraft will not be flying speed or cost, but the ability to go from downtown to downtown rather than from airport to airport.  Still, an air taxi ride will be the exception, not the rule.


It will be interesting to watch the Advanced Air Mobility industry over the next several years as they wind their way through the FAA certification process and start providing rides to the public.  My guess is that you might see a few pilot projects in two or three years, but I doubt that a fully certified, day-in-day-out eVTOL taxi service will be running in less than 4 or 5 years.  I would not be surprised if regular service started first in other countries where the certification process is not as rigorous.  

The bottom line, however, is that while this is a fascinating technology, it is not likely to be more than a niche player in the urban transportation mix.  There are some interesting partnership possibilities – with commercial airlines at one end and ride share companies like Uber and Lyft at the other – that could help the industry get off the ground (sorry for the pun).  It could be that someday your trip to another city will be a package deal that includes an Uber from your home to the nearest vertiport, an eVTOL air taxi to the airport, and a commercial flight to your destination.  Whether prices ever come down enough to make that commonplace is the unknown.  In my opinion, replicating the mobility of the Jetsons is a long way off.


1. Archer Aviation;

2. Joby Aviation;

3. Lilium GmbH;

4. Wisk Aero LLC;

5. Robin Lineberger, et al; “Change is in the air”; Deloitte Insights, 2019;

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