eVTOLution: Gaining Ground

The urban air mobility (UAM) vision of carrying a high volume of commuters and other passengers affordably and quickly to their destinations in several dozen mega-cities by 2030 has captured the lion’s share of public attention regarding electric vertical-take-off-and-landing (eVTOL) vehicles. Under the radar, however, niche eVTOL is already here.

Autonomous eVTOL drones have delivered food and medical supplies in humanitarian relief and may soon see use in firefighting and rescue efforts.

“We’re getting close to having that capability,” said Johnny Doo, the president of Alabama-based International Vehicle Research. Doo also heads the NASA Transformative Vertical Flight Working Group #4 (Public Services).

The TVF effort began in 2014 as a collaboration between the Vertical Flight Society, NASA, the American Institute of Aeronautics and Astronautics, and SAE International to examine the potential of on-demand eVTOL and hybrid eVTOL vehicles.

Doo stressed that, at least initially, eVTOL “will not replace any capability, but complement the capabilities we have” in public services provided by helicopters.

In 2020, NASA plans to demonstrate an initial capability for an eVTOL public services vehicle with protected rotors able carry a payload up to 400 pounds 25 miles round-trip in semi-autonomous mode.

For firefighting and evacuation, that initial capability demonstration could involve the delivery of masks, water and food, as well as localized aerial firefighting.

For search and rescue, an initial capability could involve one-person lift-off and autonomous return. The eVTOL vehicle would also be capable of dropping items such as a life raft, a medical pack, or a survival kit over uneven terrain at high elevations in cold weather.

For law enforcement, a similar vehicle could involve two-person lift-off and autonomous return, as well as the capability to deploy police units and deliver medical and other gear through automated capabilities on uneven terrain.

For humanitarian relief and medical operations, initial capability could involve landing on a street or roof top, autonomous operations, and food and medical supply deliveries.

“As far as competitors/OEMs on these potential applications and markets, I am not aware of anyone that has officially announced that they would be doing demonstration by 2020,” Doo said. “Several OEMs have indicated that their platform is designed to be able to do more than city air taxi missions, but you know how major OEMs are very careful regarding making any promises. I know Arnaud Didey of Neoptera is quite serious about firefighting and other ‘eVTOL for good’ missions, but their progress would be hinged on the funding timing. The mid-range Samad Aerospace eVTOL is designed for medical transport as a key mission, but may not be ready for field trial by 2020.”

“We are also working on a possibility to gain some government funding to enable and encourage the demonstration/pilot program for some of these missions, but we just started, and it may take a few months to see if this can be done and make a difference,” Doo said.

As examples of situations in which eVTOL could have helped, Doo pointed to Hurricane Maria, which killed more than 3,000 people last September in Puerto Rico and the California wildfires last November, which killed 89 people. The disasters involved congested or blocked roadways, shifting conditions, and time-critical demands on rescuers.

“If you had a short-range mobility capability, some of those people could have been evacuated in time,” Doo said. “EVTOL can help evacuate civilians.”

A two- to five-seat eVTOL firefighting craft could complement the limited number of helicopters and allow rescues of firefighters and civilians on the ground, as needed, he said.

EVTOL observers said that such vehicles also hold promise in the inspections and resulting repairs of malfunctioning power lines, which led to the California wild fires last year.

EVTOL public service projects may, in turn, build support for eVTOL in general and UAM, specifically, leading to greater UAM affordability, according to market observers.

Emergency medical services through eVTOL may be an important part of this affordability demonstration. “Smaller, less expensive, and some would argue, safer than helicopters, drone/UAS transport could improve survivability as much as 85 percent by getting the injured to emergency facilities within the golden hour after the accident,” according to the recent Urban Air Mobility—Economics and Global Markets study prospectus by the Washington, D.C.-based Nexa Advisors. “These and other predicted models boast significant societal benefits in economic productivity and passenger safety.”

Helicopter experts say that the number of fatal helicopter accidents has dropped sharply in recent years due to integrated cockpits, automation, warning systems and pilot training. Yet, the general public continues to view helicopter flight as relatively unsafe compared to airline or car travel, and removing the pilot from the loop adds another layer to the perception problem for eVTOL.

While loss of control and controlled flight into terrain are the most frequent categories for helicopter accidents, the primary cause of 75 percent of fatal, general aviation accidents is pilot error. EVTOL backers say that the key to overcoming public distrust is to show the routine nature of autonomous eVTOL flights and to have the general public gradually accept UAM as an acceptable risk, much as automobile and airline travel are viewed.

Humanitarian eVTOL flights are starting to build such a cost versus benefit case. Last December, in a UNICEF effort, eVTOL drones built by the Australian-based Swoop Aero and the German-based Wingcopter Holding GmbH began delivery of life-saving vaccines against measles, hepatitis, and tuberculosis to remote villages in the archipelago nation of Vanuatu, which has a high infant mortality rate and some 80 islands, many lacking roads. For its part, Swoop Aero said that it has been using three distribution hubs for delivering vaccines to 33 remote villages on nine islands. Such villages typically lack the refrigeration needed for care givers to keep the vaccines cool.

Wingcopter has also been involved in a similar vaccine delivery effort in Tanzania.

Eddie Bennet, the CEO and chief pilot of Australian-based Ripper Group International, which has an alliance with Swoop Aero, said the December deliveries in Vanuatu were successful in the “delivery of vaccines to inaccessible areas.” Bennet said his company has also been working on developing eVTOL for search and rescue efforts. While Ripper Group now uses helicopters to drop flotation cushions into the sea and notifies boats to pick up those stranded in the water, eVTOL “has the capacity to save lives,” Bennet said.

If eVTOL search and rescue works, benefits include an increased number of air assets involved in SAR, a reduction of operational training requirements, increased use of rescue specialists and a reduction in operational risk to air assets and people, Bennet said.

The public services aspect of eVTOL, while important, does not make the business case for the capability, unlike UAM. Traditional and start-up firms embracing eVTOL vehicles as an entrée to UAM have attracted more than $1 billion in investments, and eVTOL stands at the brink of major advances, according to the General Aviation Manufacturers Association (GAMA).

"Over the last decade we have all witnessed the rapid evolution of battery technologies, the capabilities of microelectronics and innovation in software capabilities," said Greg Bowles, GAMA's vice president for global innovation and policy. "The promise of hybrid/electric aircraft is coming to be realized; the all-electric light training aircraft of the last five-years are being joined by larger, more energetic designs which can carry four-to-nine passengers at higher speeds and longer distances."

Bowles manages the GAMA Electric Propulsion Innovation Committee (EPIC). The latter's aim is to enable the design and operation of hybrid and electric aircraft in key aviation markets around the world.

Market studies estimate 100,000 eVTOL aircraft could be flying in coming decades, creating a commercial market potentially worth trillions of dollars (see The Next Decade, p. 12).

One study by the German consultancy Roland Berger predicts that industry will field about 3,000 eVTOL passenger drones by 2025 for air taxi and airport shuttle service and 98,000 such drones by 2050 for air taxi, airport shuttle and inter-city service.

Uber is heavily committed to advancing the eVTOL concept through its Uber Elevate initiative and the company has five partners for its eVTOL aircraft: Boeing's Aurora Flight Sciences, Bell, Embraer, California-based Karem Aircraft and Slovenia-based Pipistrel Aircraft.

Bell’s Nexus eVTOL aircraft, which is to use six pivoting ducted fans attached to a fuselage that will be able to carry four passengers and a pilot, has attracted much attention from eVTOL observers. Ducts are to augment the power provided by the fans, reduce noise and improve the safety of passengers and crew.

For its part, Airbus is to fly a four-seat, quad-ducted propeller eVTOL aircraft called CityAirbus, in the coming months. Airbus has been flying its smaller, unmanned Vahana eVTOL aircraft since January last year. Airbus and a number of non-traditional companies appear to be angling to compete with Uber in the UAM business overall rather than merely selling eVTOL aircraft to future UAM providers, such as Uber.

Such companies include California-based Joby Aviation, German-based Lilium and Volocopter and California-based Kitty Hawk Corp., the latter being financially supported by Google co-founder Larry Page.

Nexa Advisors is conducting a UAM economic study for aerospace companies looking to determine a business case for their entry into the UAM market, which the compay said it will deliver to its clients by the middle of this year. The study includes the 70 most populated urban areas worldwide, ranked by Gross Domestic Product — a set of cities with more than $24 trillion in GDP — and some smaller cities, such as Salt Lake City and Syracuse, that may play important roles in UAM development and testing. The Nexa study will compare the business cases for UAM in the cities and, while GDP is an important factor in determining which cities are likely to be profitable for UAM, a variety of other factors come into play, such as the number of vertiports in a given city and the amount of other infrastructure and automation.

For example, Tokyo, the leading city by GDP, has a relatively small number of operating vertiports as a result of regulations and noise concerns, while Sao Paulo — the 15th ranked city by GDP — has the most vertiports of any urban area in the world, with about 270. Airbus, which established a UAM unit last June, appears to be banking heavily on Sao Paulo, where the company established its Voom helicopter booking service in 2017.

While some industry experts have said that eVTOL will revolutionize air transport by the mid- 2020s, others believe eVTOL will ramp up incrementally, especially given the challenges of unmanned aircraft system traffic management (UTM) and the regulatory hurdles eVTOL faces at the FAA.

“We think this will be an evolutionary process,” said Will Heyburn, the head of corporate development and business processes for BLADE, a New York-based flight services company. “It takes Boeing seven years to get approval to add an extra row of seats to the 737.”

BLADE has partnered with Lockheed Martin’s Sikorsky to use an S-76 helicopter to provide insights to Sikorsky on the logistics of UAM and what a future eVTOL design by Sikorsky might entail.

On UTM, industry has begun making proposals on what such a system should look like.

“Evolution in air traffic happens slowly, but it happens, and it is lasting,” according to the Airbus UTM Blueprint. “Take the introduction of radar services at individual airports with TRACON in 1981; by the 2000s, it had morphed into consolidated operations that could serve dozens of airports from a single facility. The choices we make now will affect the world for generations to come.”