Will China Beat the US to Commercial eVTOL Services?

The Civil Aviation Administration of China has accepted the first application for type certification of an eVTOL vehicle. This might open the floodgates.

Personal air mobility is a concept as old as the helicopter itself. Bell Aircraft, in fact, promoted early Bell helicopter prototypes as personal air vehicles, suggesting a future with a helicopter in every driveway. That never happened, but the development of lightweight batteries and electric motors that allow distributed lift through multiple rotors has created a new gold rush as small garage startups—and major players like Boeing and Airbus—race to develop electric eVTOL passenger-carrying vehicles. The goal is for autonomy, but it’s now widely believed that piloted vehicles will be the first in the air, and the Chinese want to pioneer this new form of aviation. Will they? And just as significantly, will eVTOL travel really revolutionize intracity transport?

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Episode Transcript:

It may seem hard to believe, but in the early days of the helicopter there were serious doubts about whether vertical flight would ever have a practical use.

Bell Aircraft, one of the pioneers of commercial helicopters along with Vought-Sikorski, produced a promotional film that suggested the use of helicopters as personal air vehicles, taking you from your driveway to the shopping plaza in minutes. Of course, the pilot training and skill required to safely fly a helicopter is significant, and only the most affluent use helicopters as personal transportation today.

But that may be changing. Dozens of mobility companies, from garage startups to heavyweights like Boeing and Airbus, are racing to use advanced composite structures along with lightweight batteries and electric motors driving multiple lift rotors, to create what are essentially gigantic versions of commercial drones.

The goal is simple: create a form of intracity transport that does from rooftops and parking lots what taxis do on the streets today. Obviously, not everyone can qualify as helicopter pilot, and it is widely assumed that eVTOL transport will be autonomous. But like autonomous driving for road vehicles, it’s more difficult than it looks. 

Many experts believe that the initial generation of flying taxis will be piloted, in the same way that taxis are driven by cab drivers today, but with flight control systems that are highly redundant, highly automated and will use a pilot training and licensing system that is tailored to these unique vehicles.

Technically, it’s easy to see why. Conventional helicopter flying using cyclic and collective control inputs is not only tricky, but is also technically challenging for the machine itself. In forward flight, the advancing rotor must have a lower angle of attack than the retreating rotor, to account for the forward motion component of the air velocity over the blades.

This requires a complex mechanism, and to complicate it even further, the rotor head itself must tilt to induce motion in the desired direction of travel. The blades require another degree of freedom, using bearings or a teetering hinge to allow this movement. Look at a helicopter rotor head and you can see the complexity in the multiple shafts, linkages and bearings required.

The eVTOL does away with this complexity by its very nature. Power is distributed amongst multiple electric motors, each spinning a smaller rotor, with a far simpler fixed pitch propeller. Counterrotating power plants on each side of the vehicle eliminate the need for an anti-torque tail rotor, and with a fly by wire system operating with stability control, it should be possible to keep the vehicle stable by varying individual motor RPM automatically.

This could simplify the pilot’s workload, possibly allow a licensing scheme that would make it cost effective to operate air taxi services with a professional in the cockpit. And of course, the more advanced the stability control systems, the more likely that a private owner with minimal skills beyond those needed to drive a car will be able to operate one of these things. Eventually, of course, they will be fully autonomous.

Right now in China, two potential vehicles are in that country’s Civil Aviation Administration certification process, the Ehang EH216-S and the Aerofugia AE200. The Chinese have several advantages in developing this technology. Risk tolerance is government-determined in China, and once certified, their airframe makers and taxi operators will not face the daunting prospect of American tort law and liability insurance.

For the Chinese government, it’s an opportunity to leave the world an important new transportation technology, and potentially become a global center of excellence for electric air mobility. Without doubt European and American authorities are watching with interest, as are the aircraft makers.

Is their smart play to lead in this technology, or wait and see?

We’ll have to wait and see.

Written by

James Anderton

Jim Anderton is the Director of Content for ENGINEERING.com. Mr. Anderton was formerly editor of Canadian Metalworking Magazine and has contributed to a wide range of print and on-line publications, including Design Engineering, Canadian Plastics, Service Station and Garage Management, Autovision, and the National Post. He also brings prior industry experience in quality and part design for a Tier One automotive supplier.