The nascent electric vertical takeoff and landing (eVTOL) aircraft market has attracted more than $1 billion in seed capital, 125 aircraft designs, and numerous private sector, academic, and government studies, many of which paint a grandiose vision. NASA said two recent studies it funded suggest a vibrant future for urban air mobility (UAM). Crown Consulting predicts as many as 500 million flights a year for package delivery services and 750 million flights a year for air metro services by 2030, while Booz Allen noted the significant potential of UAM to transform the nation’s air transport system. Prototype and mock-up aircraft were the darlings of the summer 2018 airshow season.
At Farnborough, the UK government announced that it is investing $436 million in hybrid electric aircraft development and related projects; super car maker Aston Martin unveiled the Volante Vision, a three-seat hybrid electric aircraft; and Rolls-Royce took the wraps off a slightly larger four- to five-seat model powered by the ubiquitous M250 helicopter turboshaft. Boeing said it is allying with SparkCognition to form BoeingNeXt to work on urban air taxis as well as unmanned cargo and supersonic aircraft. At EAA AirVenture in Oshkosh, Wisconsin, Assen Aeronautics showed off its A1 ducted fan “flying bike,” Opener brought two BlackFly “personal aerial vehicles,” and Workhorse displayed its two-seat “SureFly” quadcopter.
These new class of aircraft are portrayed as a $30 billion economic engine with the potential to ameliorate the looming urban ground transportation infrastructure crisis, bring new dimensions of speed and convenience to the masses, and transform the vertical lift industry all within the next decade—or sooner, if the predictions of the likes of Uber Air is to be believed.
While major aviation industry players—including Airbus, Boeing, Bell, Embraer, Intel, Amazon, Honda, Toyota, and Uber—have taken notice, stood up technology teams, and devoted resources to exploring this new market space, the essential trinity needed to bring it to reality—vehicle technology at an affordable price, reliable low altitude airspace management, and workable government regulation—remain works in progress. Add to this the fickle winds of public acceptance of a situation where hundreds, even thousands, of low-altitude air vehicles are added on a daily basis to an urban environment and the future path of eVTOL is anything but certain. Especially in markets such as Los Angeles and New York, where the regular presence of a few dozen helicopters draws regular public opinion slings and arrows and is an easy target for opportunistic politicians and lazy local media. The plan is for many more eVTOLs than helicopters. At Congressional hearings in September 2018, Thomas Prevort, Uber director of aerospace engineering, said the company intends to fly “thousands of aircraft in each metropolitan market that we serve.”
That could be a recipe for disaster, according to Chris Van Buiten, vice president of Sikorsky Innovations. At the 2018 Association for Unmanned Vehicle Systems International conference, Van Buiten said, “I am extremely nervous. Until you are ready to have your vehicle fly with your family onboard every day, you are making a toy.” He noted that the accident rate for civil helicopters—which have been in production since the 1940s—is one per one million flight hours, but that eVTOL system architects envision 50,000 of their aircraft flying 3,000 hours each annually, predominantly in urban areas. Van Buiten postulated that the emerging eVTOL industry simply could not survive with an accident rate similar to today’s safest helicopters. “So if you aren’t thinking about 100 times of what the best safety standard is in the helicopter industry right now, you are going to ruin it for us all. The bar is very high, and it needs to be,” he warned. However, he noted it is achievable. “The technology exists and the standards need to be vigorously adhered to. Urban mobility is going to happen.”
The questions remain though, when and in what form? Regulation will play a penultimate role in the industry’s future and there are those such as Joby CEO JoeBen Bevirt, who are pushing for more relaxed vehicle standards, such as those under Part 23 for light aircraft, versus more conservative advocates such as Van Buiten, who suggest a standard equivalent to Part 29, the current certification standard for turbine twin helicopters weighing more than 7,000 pounds. Regulators are currently wrestling with this, as well as the associated air traffic control dynamics, and not nearly fast enough for many in Congress or industry. At House aviation subcommittee hearings in 2018 chairman Frank LoBiondo (R-NJ) said that the FAA “needed to stay ahead” of new technology such as eVTOLs so the U.S. can maintain its “global leadership in aviation.”
As with other aircraft types an international industry standard must emerge, and that dialogue has begun. The U.S. General Aviation Manufacturers Association (GAMA) and member companies have been in discussions with EASA and the European Commission with regard to related issues and regulatory framework. The FAA is still ironing out the related specifics as well, including whether eVTOLs will be governed under Part 21.17(b) (special class) or Part 23 with special conditions, how to deal with distributed, electric, or hybrid propulsion, thrust-management systems, full autonomous flight control systems, and installation of rechargeable lithium-ion battery systems.
Still, regulation aside, there is the matter of public acceptance of the new technology. In the U.S., plans to hold a series of “Grand Challenges” beginning in late 2020 for UAM market entrants to promote public confidence in related new vehicles and supporting technology, the agency announced. “The vision to revolutionize air mobility in and around metropolitan areas is one of the most exciting frontiers in modern aviation,” said Jaiwon Shin, associate administrator of NASA’s Aeronautics Research Mission Directorate. “NASA is committed to working with our industry and government partners in any way we can to safely integrate these new options for passenger and cargo air transportation services into our skies,” he said. The first “Grand Challenge” will demonstrate the “safe operation of a piloted or remotely piloted aircraft capable of carrying at least one adult passenger within a simulated, challenging urban environment.”
But even if eVTOLs win public acceptance and clear regulatory and technological hurdles, can OEMs and service providers deliver the technology at a price the general public can afford? Uber claims it can field eVTOL service at $1.36 per mile, a rate comparable to urban ground fare, but others are skeptical, pointing to comparable and false, claims made about operating economies in the early days of helicopters. To hit that goal would require economies of scale unseen to date in aviation. The last time anything remotely close was attempted was the very light jet air-taxi model typified by the Eclipse/DayJet pairing of over a decade ago, an experiment that ended badly for all concerned.