Autonomous Vehicle Will flying taxis make self-driving cars obsolete?
While mobility experts focus on autonomous vehicles (AVs) and the potential they have to alter our transportation habits, another phenomenon is threatening to supersede even these modern innovations: flying taxis. At present, the market for urban air mobility (UAM) is anticipated to be worth USD$300 billion by 2030 and USD$1.5 trillion by 2040.
Like in the movie Blade Runner, these gliding, floating transport vehicles could potentially save the average commuter minutes or even hours otherwise spent stuck in traffic and/or subject to road accidents and detours. The possibility of being able to navigate through the skies in three-dimensional space is tantalizing, but whether it comes to fruition in the near-term future depends on a number of factors.
It's obvious when you're on the road—traffic, noise, and pollution lead to the thought that if you only had a flying car, you could literally leave congestion behind and just fly away to your destination.
As it turns out, you're not the only one to have this fantasy; ever since the dawn of aviation, the idea of personal transport as unlimited as the heaven has captivated both travelers and inventors alike. However, over time, airplanes rapidly advanced in both complexity and cost while the price and convenience of automobiles became ever more palatable to the everyday commuter. While the concept of a flying car has been with us for decades, it wasn't until recently that established aerospace firms, as well as nimble startups, realized that these mechanized contraptions were worthwhile to revisit.
These days, when one thinks of a flying vehicle, one is likelier to imagine something more akin to a helicopter than an airplane. As miniature flying drones became more stable and aerodynamic, different companies began exploring larger versions that were capable of carrying more and more weight.
Eventually, it was conceived that such machines could carry passengers just as easily as cargo or cumbersome electronic equipment. As tests showed, maneuverability and power requirements were very manageable, and it was speculated that the mass manufacture of such vehicles could bring down unit prices to an affordable range.
After about 2010, the idea of fleets of flying taxis seemed less and less fantastic and more like an inevitability. Fully functioning prototypes were built and tested. Companies were formed, and existing aviation enterprises began to see a market materializing. For large established ridesharing firms, the writing was on the wall; flying taxis would need to be more than just considered for the future; they needed to be aggressively pursued and incorporated into these ventures' portfolios.
At present, the market for urban air mobility (UAM) is anticipated to be worth USD$300 billion by 2030 and USD$1.5 trillion by 2040. As companies begin to operate fleets of flying taxis, it's expected that air mobility would cut into business for ground-based mobility services, particularly in congested urban environments on fixed routes, say, from a city airport to a major downtown office or transportation hub.
In theory, full autonomy (pilotless operation) of a flying taxi would be less complex than navigation on roads where surrounding and oncoming traffic on the latter could be dense. On roads, potential obstacles can rapidly inject themselves into the path of an AV's trajectory, whereas this would be unlikely in the sky, at least initially. But this supposition assumes that skies would not ultimately be thick with other flying vehicles. This comparison also might incorporate drastic assumptions about the weather, which could change dramatically over the course of even a single flight.
Whether companies that want to get into the flying-taxi market have taken all these factors—as well as potential state and federal regulations—into account is another story.
Flying cars have been an on-again/off-again dream ever since the invention of both the automobile and the airplane. For years, the covers of Popular Science and Popular Mechanics magazines featured renderings of car-plane hybrids of the future.
Would-be engineers realized that vehicles capable of flight would need to be rugged, robust, and heavy enough to withstand the rigors of driving while also being aerodynamic and light enough to fly. The problem is that these two goals tend to oppose one another—like a car, the objective is usually to fight horizontal air friction, while as a plane, the goal is to overcome vertical gravity via lift.
Over the years, engineering compromises tended to produce either a car that was an inferior airplane or an airplane that was a substandard car. In the earliest days of automobiles, when airplanes were first getting off the ground, it may have seemed that aircraft had substantial advantages over cars; they weren't limited to roads. In the era of early aviation, America had much vast open space in which to take off and land, and pilots didn't need a whole lot of training to operate their crudely constructed gizmos.
But what probably got cars to "take off" instead of airplanes—at least from a sales perspective—was the paving of much of the country's roads, along with the standardization of automotive shock absorbers. These two developments had the effect of making the average automobile trip far more pleasant than in the early years of cars when what few roads existed were bumpy and might be covered with up to a foot of dirt or mud.
The separate advancements of cars and airplanes didn't stop some entrepreneurs from trying to combine the two machines. One of the first to do so was aviation pioneer Glenn Curtiss, who built the Curtiss Autoplane in 1917. The Autoplane was a prototype airplane/car that debuted at the Pan-American Aeronautic Exposition in New York. Surprisingly stylish, it looked like a very modern car that had an addition of bolt-on wings and a removable rear propeller. But with America's entry into World War I came the need to build military planes, not airplane-car hybrids. The Autoplane was dismantled for parts.
In 1947, an inventor named Robert Fulton introduced the Airphibian—essentially, a small airplane whose wings and propeller could detach for road use but which otherwise retained the appearance of an aircraft fuselage on wheels. In 1950, the Airphibian received certification from the U.S. Civic Aeronautics Authority, the predecessor of the Federal Aviation Administration (FAA). Although the Airphibian actually went into production, significant numbers were never constructed due to its relatively high cost.
Several years later, the Aerocar was a small vehicle created by engineer Molt Taylor that could tow a small trailer carrying the craft's wings and tail behind it when it was on the ground. The Aerocar also received certification from the Civic Aeronautics Authority. But more importantly, it complied with all U.S. road vehicle specifications. Unlike earlier hybrid attempts, the Aerocar looked like a car and was comfortable and safe to drive. As a plane, it had a range of 300 to 500 miles.
In the 1960s, Taylor struggled to find any business willing to finance production of the Aerocar. By 1970, he got lucky when Ford Motor Company conducted a study to see if there was a market for the machine. Ford calculated that it could probably sell at least 25,000 of the hybrids initially, but worried about regulatory hurdles and safety considerations. The U.S. Department of Transportation, in particular, shared the automaker's safety concern. In order to meet safety requirements, the Aerocar would likely have had to be of a heavier-duty construction, inhibiting its ability to fly.
Fast-forward to today, and prototype flying cars look less like airplanes and more like oversized drones that are capable of vertical takeoff and landing (VTOL). Multiple redundant rotors make these VTOLs both safer and cheaper to operate than traditional helicopters.
The online Vertical Flight Society tracks VTOLs in development and maintains a directory (viewable here) of more than 250 VTOL designs. They're divided into models which use the same motors for both lift and horizontal movement, and those that feature independent motors for each of these functions.
Another key difference between today's flying taxi concepts and those of yesteryear is that in almost every case, today's vehicle propulsion systems are electric, which changes the dynamics of cost, noise, weight, reliability, and pollution.
Advances in materials, batteries, and motor sizes have meant that the commercial potential for air mobility is much closer to being realized than it was in the past. Greater control over rotor rotation speed and torque than with combustion engines means that electric-propulsion VTOLs (eVTOLs) are more efficient in terms of power-to-weight ratios. More power is needed for takeoffs and landings than for horizontal propulsion once a vehicle is airborne, but electric motors can handle this difference very well.
Like land-based AVs, flying taxis—if they're ever to be pilotless and automated—will need a broad array of sensors, not just scanning in two dimensions as AVs do on the ground, but in three dimensions. If these flying taxis ever drive on roads as well as fly, certification in the U.S. would need to come from both the National Highway Traffic Safety Administration (NHTSA) and the FAA. In Europe, the equivalent bodies are the European Conference of Ministers of Transport (ECMT) and the European Aviation Safety Agency (EASA).
For this last reason, and because land-based operation would only add to the complexity of autonomous navigation, flying taxis of the future will likely limit their movement to flight only. This, therefore, raises the questions of where they'll take off from and what they'll land on. In almost every scenario envisioned so far, there would be a limited number of heliport-like pads where passengers could embark and disembark from their flying-taxi journeys.
Companies getting into the flying vehicle space include Canada's Opener and the U.S.'s Kitty Hawk—both of which are backed by Google co-founder Larry Page. In these cases, because of their limited speeds and altitudes, neither venture foresees the need for a personal pilot's license for their one- or two-passenger gliding machines.
In Massachusetts, startup Terrafugia has gotten both road safety and FAA approval for its Transition model flying car. At the same time, Slovakia-based Aeromobil is awaiting approval from EASA for its Aeromobil 4.0 flying car.
Both companies are now turning toward a VTOL design for their latest models. In Terrafugia's case, the TF-2 is a removable passenger "pod" that can be docked to either car wheels or an airframe. In Aeromobil's case, the 5.0 is a car that drives to a helipad before wings fold out from its body, and it takes off vertically.
Ridesharing firm Uber's Elevate flying-taxi division is using an array of aviation vendors to build prototype vehicles for the company, including Boeing, Bell, Embraer, Karem Aircraft, Pipistrel, Jaunt Air Mobility, Hyundai, and Joby. In late 2019, Joby announced it had won the contract to be Uber's vendor of choice for the first Elevate/Uber Air eVTOL fleets.
Uber has set a date of 2023 for when it expects its pilot air mobility service to "lift-off"—initially, from the cities of Dallas, Los Angeles, and Melbourne. If successful, the service will likely be rolled out to other global cities shortly thereafter. Uber's "Skyports" will be located in city centers—on building rooftops as small as one acre—and will be designed to handle up to 1000 discrete landings per hour. Like Airbus (see below), Uber desires to start a wireless UAM traffic control network to manage its flying taxis and airborne delivery drones.
Aviation giant Airbus has decided to see if air mobility is in its future by testing City Airbus, a prototype remotely piloted, eight-propeller, four-passenger eVTOL flying taxi, for which it's already operated 100 successful flights. Previously, the company's A-Cubed group tested an eight-motor, single-passenger eVTOL vehicle called the Vahana in more than 130 flights before retiring it. Along with these tests, the company is working on a UAM vehicle unmanned traffic management (UTM) network that will oversee Airbus' own taxis and delivery drones as well as those belonging to other operators.
In 2018 and 2020, Japan's Toyota invested USD$394 million in aforementioned flying vehicle firm Joby, based in California. Joby has stated it would like to operate its own flying taxi service separate from Uber Air (although it would be part of Uber's mobility network), and it's using Toyota's and other investments to ramp up production of a six-rotor, piloted, 60-mile-range five-seat eVTOL.
In 2019, Germany's Porsche announced it would be teaming with the U.S.'s Boeing (specifically, the latter company's Aurora Flight Sciences division) to create a luxury eVTOL flying taxi. So far, a prototype vehicle has flown several test flights in Virginia, but it's unknown when any potential service would launch.
Other players in the flying-taxi space will likely include Germany's Volocopter, which has plans to co-launch a flying taxi service in Singapore and other Asian cities, and China's EHang, which has plans to operate UAM services in Guangzhou, China, and Seville, Spain.
But before these players can begin operating, some concerns like onboard battery performance and noise likely need to be addressed. Another issue is privacy; if flying taxis get too close to homes and businesses, people may have worries related to surveillance.
Safety will be even more of an issue than with r AVs because a flying taxi can't just "pull over to the side of the road" if there's a problem; navigation and backup systems will have to be incredibly reliable compared to AVs (in general, aviation safety often differs by orders of magnitude from land-based vehicular safety).
Safety is not only a concern for people within a flying taxi, but also for people on the ground. Although skies have exponentially more space than roads, every so often, we hear about airborne "near-misses" that have the potential to be catastrophic; the more flying taxis there are in the sky, the more this will have to be taken into consideration.
For now, both the FAA and EASA have begun the certification process for VTOLs. In the case of EASA, a special condition certification for VTOLs of 3,175 kg or less carrying nine passengers or less was adopted into its aviation regulations in 2019.
As for how flying taxis fit into the overall mobility mix, it's probable that road-based vehicles (including AVs)—possibly operated by the respective flying taxi firms—would bring passengers to takeoff pads and pick them up again at the other end of the journey.
Then there's the hurdle of cost.
For now, Uber's Elevate has estimated that a single trip in a flying taxi might cost around USD$5 per mile, but the company ideally would like to lower that cost to under USD$2 per mile in the near-term, with a target of less than 50 cents per mile in future years. The idea is that eventually, the cost of using Uber Air would be cheaper than the cost of ground-based mobility services. Uber says that based on these prices, its target market includes as many as 700 million potential users.
For its part, Joby has said it wants to set the cost of riding in its flying taxis on par with the price of ground-based mobility services. Whether this will be possible for either firm will likely depend on the speed and efficiency of both forms of transport.