Airborne cabs could make sure we're never stuck in NYC traffic again. But are they a flight of fancy -- or a better way to travel?Soon you’ll be able to go to work in a flying taxi
Late for work? Imagine skipping the subway and instead heading to your local “vertiport,” where you can hop into an aircraft the size of an SUV that runs on electricity and works pretty much like an elevator.
Get in, punch in your destination, and off you go. Alone.
It may sound like an episode of “The Jetsons,” but electric air taxis are a form of transportation that is coming to Dubai in just a few months. And investors hope American cities aren’t much far behind.
Insiders call the new breed of flying machine “e-VTOLs,” (pronounced “EE-VEE- talls”), an acronym for “electric vertical take off and landing.”
We want it to be on-demand. You push a button and a car will pick you up and take you to a vertiport and the next aircraft will leave in minutes.
Exotic prototypes are being designed, built and flight-tested by companies ranging from Airbus to startups bankrolled by tech billionaires such as Google co-founder Larry Page.
“Dozens of companies . . . are investing in e-VTOL aircraft,” observes advocate Mike Hirschberg, executive director of the American Helicopter Society International. “They are proving that not only is e-VTOL technology feasible, but it can make a compelling business.”
The business case is being made most eagerly by Uber. The San Francisco-based rent-a-ride provider wants to live up to its name — German for “over” — by making it possible for customers to use their Uber cellphone app to order up a lift by car or air taxi or a combination of the two, whatever is most convenient and economical. Uber sees e-VTOLs as the answer.
“Flight is a natural extension of what we’re doing,” said Jeff Holden, Uber’s chief product officer, who created Uber’s self-driving-car laboratory in Pittsburgh.
Uber will host an invitation-only “Elevate Summit” in Dallas from April 25-27. There, Holden and others from Uber, along with leaders of companies developing and investing in e-VTOLs and related technologies, will discuss the many issues raised by the concept of urban air transport.
“All these benefits may seem great in theory, [and] far-off in practice, but we believe VTOLs could be flying on Uber within a decade,” Nikhil Goel, Product Manager, Advanced Programs & Uber Elevate, told The Post. “We’ll be talking about timeline in more depth at the summit.”
It’s a 21st century take on a notion that’s been around since the advent of powered flight.
“A vehicle that can take you from your home to your office, to your country club, to your bank or to your friend’s house, by air or by road, whichever is most convenient, will have a vast usefulness,” test pilot James G. Ray told a Philadelphia conference on VTOL aircraft — in 1938.
Lots of flying cars have been designed and built since then, yet the only place you ever see them is on covers of Popular Science or Popular Mechanics. One big hurdle: A car able to rise into the air and fly needs vastly more power than one that just rolls on wheels. Most e-VTOL developers aren’t even trying to make their vehicles “roadable.”
“Don’t call them flying cars! They are not flying cars!” beseeches Hirschberg. “Hardly anyone today is looking at concepts that can both fly and drive. VTOL vehicles are never going to be as cheap as cars, so why would someone want to drive an aircraft that costs hundreds of thousands or millions of dollars on the highway?”
Configurations vary, but many e-VTOLs look and work something like quadcopters and other hobby drones — one source of inspiration for the concept. Advances in batteries, electric propulsion, artificial intelligence, and sensors, coupled with lightweight composite materials, now make it possible to think about sizing little drones up to carry people.
To keep competitors in the dark, some e-VTOL developers — like Google co-founder Page’s startup Zee.Aero — refuse to talk about their designs. But most use some combination of battery-driven electric motors to run propellers, rotors or fans held in arrays around the passenger cabin or in rows on top of, or embedded inside, wings. Some have tilting wings and a tilting “canard,” a stubby wing out front to add stability.
The idea of helicopter taxi services was once popular among urban planners and architects such as Le Corbusier and Frank Lloyd Wright, said Roger Connor, curator for rotorcraft and drones at the Smithsonian National Air and Space Museum. Various companies began offering helicopter air taxi services in New York and other big cities after World War II, Connor said, but they proved unprofitable.
“Demand was high, but profitability was elusive, because even the most efficient twin turbine helicopters could not keep the seat-mile costs to an economically viable level,” Connor said.
Advocates say e-VTOLs will work for urban transport where helicopters haven’t because, being electric, they will be cleaner, quieter and cheaper.
“Helicopters are too noisy, inefficient, polluting and expensive for mass-scale use,” a 100-page white paper from Uber last year argued. “VTOL aircraft will make use of electric propulsion so they have zero operational emissions and will likely be quiet enough to operate in cities without disturbing the neighbors.”
Some experts take strong issue with the latter point. Just because electric motors aren’t loud doesn’t mean e-VTOLs will be quiet, said John Hansman, a Massachusetts Institute of Technology aeronautics and astronautics professor. Electric VTOLs, after all, still have to spin rotors, propellers or fans at speeds that create substantial noise.
“Even on a jet engine, most of the noise is not the engine, it’s either from the fan or the exhaust jet,” Hansman said. Take the buzz of a toy drone and scale it up to a 4,000-lb. vehicle and “it’s probably not going to be silent,” he said.
But given growing road congestion and commuter frustration, Hansman added, “There is clearly a market.”
Promoted by NASA research on electric aircraft propulsion, the e-VTOL movement was well underway when Uber joined it, but “Uber can accelerate this,” Holden said. Uber doesn’t plan to build its own e-VTOLs, he said, but “we’re coming into this intending to operate a network of aircraft.”
Uber wants to be a catalyst for e-VTOLs, dangling the carrot of its 40 million monthly worldwide users and nearly $70 billion valuation to spur technological, regulatory and cultural progress.
“We want it to be on-demand,” Holden said. “It may very well be multimodal, which means that you push a button and a car will pick you up and take you to a vertiport, and then the next aircraft will leave in the next couple of minutes. We don’t think it will be one of these things where things are scheduled, like an airport where you buy a ticket for a certain time or something like that. That’s not the way Uber rolls.”
For the scheme to work, the Federal Aviation Administration will have to figure out how to certify e-VTOLs as safe and adopt air-traffic rules to govern them. Cities will have to build or be equipped with vertiports and other infrastructure. Citizens will have to accept the idea of e-VTOLs crisscrossing city skies.
They’ll have to accept the cost, too. Uber calculates that a 50-mile air taxi trip “might initially cost around $129 and eventually be as cheap as $20,” said Uber’s Goel, as ridesharing and higher demand for such rides make it easier to pay for e-VTOLs.
Elsewhere in the world, the authorities are less picky. The Dubai Roads and Transport Agency announced in February that Chinese drone technology and services company EHang will be allowed to fly air-taxi trips in that United Arab Emirates metropolis starting this July using its EHang 184 Autonomous Aerial Vehicle.
The EHang 184 is a one-passenger “quad multicopter” with a total of eight propellers stacked in vertical upper and lower pairs that turn in opposite directions at the end of four arms.
The propellers are run by electric motors powered by lithium polymer batteries. EHang says the 184 can fly one passenger weighing less than 220 lbs. on a trip lasting about 23 minutes.
Neither Dubai nor EHang offered details, but news coverage posted to EHang’s website said that while the 184 is designed to be autonomous, initial flights in Dubai will be remote-controlled from a command center able to land the aircraft immediately in case of problems.
“I’m not getting in one,” said Eric Raymond, who has designed and flown solar-electric and battery-powered electric airplanes since 1989. Raymond — a former hang-glider aerobatics world champion — thinks none of the e-VTOL designs he’s seen are practical or safe.
Batteries are heavy and as a rule can store only a fraction as much energy as aviation fuel, so e-VTOLs are going to have extremely limited flight endurance, Raymond noted. And if they lose power in flight, he said, e-VTOLs without good-sized wings to glide down on or rotors big enough to “auto-rotate” like a maple seed are likely to drop like a rock.
Reading Uber’s white paper offered Raymond no comfort on that point.
“They’re promising ballistic parachutes, which I’ve actually used and tested,” he said. “I have one in my airplane.” But below 100 feet of altitude, the parachute doesn’t have time to deploy, he said, and even if the parachute opens, “You could go into power lines, trees, water. The idea of a ballistic parachute is you’ll probably survive the crash.”
Urban e-VTOL advocate Hirschberg and other proponents concede that the technology still poses challenges, but think they can be overcome. “These e-VTOL aircraft aren’t ready now for passenger flights, but in five or 10 years, with advances in electric batteries, motors, and other technologies, Uber’s vision could become a reality,” Hirschberg said. “This isn’t about today. It’s about tomorrow.”
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