The Future of Advanced Air Mobility

Tensions Surface Over Timetable and Scope For eVTOL Type Certification

Discreet tensions over the timetable for finalizing the regulatory framework for type certification of eVTOL aircraft surfaced during this week’s Forum 76 conference organized by the Vertical Flight Society. In an October 8 virtual roundtable, Mark Moore, Uber Elevate’s engineering director of aviation, said he is increasingly eager for the FAA to publish its long-anticipated Special Conditions guidelines for eVTOL type certification. In the same discussion, he repeated his concern that regulators may be aspiring to an unreasonably high safety benchmark for the new category of aircraft.

“Every day, I’m holding my breath for the Federal Register to show the special conditions basis for eVTOL developers,” said Moore, who is leading technical aspects of the ride-hailing giant’s plans to launch its Uber Air taxi network. “Such great work has been done with Amendment 64 and Part 23 [regulations] and there is consensus, but we’ve got to open up the path clearly and publicly, and I’m disappointed that this hasn’t happened yet. The industry will be blocked until we push this through.”

In response, Wes Ryan, the FAA’s lead for unmanned and pilotless aircraft technology, acknowledged that while publication of the document would be “nice to have,” further negotiations are ongoing with several of the companies that have filed early applications for type certification. He explained that these discussions involve proprietary information and that the agency is working to determine how specific the requirements should be. “We hope to get something that is fairly generic, but what we don’t want to do is publish something that is so open [in terms of requirements] that anyone could meet them.”

In Ryan’s view, the time being taken to finalize rules should not be a delaying factor for eVTOL development. “We have too many people saying that they are waiting for government, but it is the companies who are testing and developing technology that can move this forward,” he added. “Don’t wait for government; the industry has to keep developing technologies such as batteries and detect-and-avoid and ensure that these are safe for civil use.”

Making points addressed to EASA, which in mid-November is preparing to publish means of compliance for the Special Conditions it issued last year, Moore expressed concern that the standards will be based on a safety factor of 10 to the minus 9, as compared with rates for currently operated fixed-wing aircraft and rotorcraft of 10 to the minus 7. He argued that regulators may be excessively focused on system failure rates, and paying less attention to operational safety failings.

“If we are setting [safety] requirements, we need to know the cost and how much value it is adding,” he stated, noting that “10 to the minus 9 eliminates most system failures, but may not have much impact on safety errors happening at an operational level.” In his view, it is not valid to hold eVTOL aircraft for UAM operations to a markedly higher safety standard than current helicopter air taxi services in and around cities.

EASA’s head of vertical takeoff and landing, David Solar, replied that the agency is paying more attention to operational aspects of safety, while adding that the industry still has a lot more work to do on the factors needed to support the launch of commercial services, including unmanned traffic management, infrastructure, and public acceptance. He suggested that the highly ambitious UAM sector may have to take a more gradual approach. “The reality is that most [eVTOL] companies want to start commercial [passenger] operations within the next five years,” he reflected. “At the end of the day, if you are going that way there is an associated cost [in terms of time and money], but if you wanted to start with something involving cargo [flights] in rural areas you would not be bound by the 10 the minus 9 safety standard. So maybe take a step-by-step approach. This is all part of the dilemma of reconciling industry plans with a risk-based approach to safety.”

Starr Ginn, who heads NASA’s Advanced Air Mobility program, echoed this call for a thorough and patient approach. Her team is preparing a helicopter to conduct test flights in “surrogate” UAM operations to assess real-world safety contingencies. “These [eVTOL aircraft] are like X-planes and the technologies they use are quite new,” she maintained. “The robustness is being developed. We’re still expanding the envelope and can’t start the certification process until then and we can’t do it without seeing operational data.”

Even in the wake of economic dislocation resulting from the Covid pandemic, Uber continues to set an aggressive pace for its plans to launch Uber Air in two or three early-adopter cities, including Dallas and Los Angeles. Publicly, the group is still committed to a launch in 2023, although Moore did concede that this may now drift into the early part of 2024.

However, Moore sought to play down expectations for rapid growth, stating that the company will operate a relatively small number of flights in the first three of four years and that it will take another 10 to 20 years for UAM to get anywhere close to the scale of existing business aviation charter services. But his tone was still largely bullish as he insisted that it will be the entrepreneurial start-up companies that lead the way to what Uber and other pioneers still characterize as a promised land of revolutionary change for air transportation.

“This is definitely happening, and it's small companies who are the leaders,” Moore concluded. “Boeing and Airbus will not be the leaders, and that especially true after Covid. [Companies like] Lilium and Joby are burning hundreds of millions per year and if we muddle safety requirements we are not going to get everything right with the new set of technologies. So let’s be reasonable and safe as possible, but not drag these companies through requirements hell.”