US Air Force Moves to Boost eVTOL Development
The service hopes to help aircraft developers get FAA certification as it weighs becoming an “early adopter” of air taxi vehicles for utility missions.
By Richard Whittle
Vertiflite, March/April 2020
The Air Force marked the 116th anniversary of the Dec. 17, 1903, Wright brothers flight at Kitty Hawk by issuing a request for information (RFI) aimed at helping foster a new powered flight revolution — electric or hybrid electric vertical takeoff and landing (eVTOL) aircraft — eventually self-flying.
Just two months after that RFI, on Feb. 25, the service dipped another toe into the eVTOL waters by issuing an “Innovative Capabilities Opening” solicitation to eVTOL developers to apply for Air Force support if they plan to meet certain performance criteria and will conduct a “first full scale flight prior to 17 December 2020.”
This solicitation said that for companies with aircraft that qualify, “the government will offer opportunities for collaborative test planning with the potential of offering test assets and expertise. The intent is to accelerate commercial aircraft certification while assessing the value of early adoption and fielding by the government.”
The service’s announcements didn’t rule out any type of VTOL aircraft able to carry people or cargo, but it’s clear conventional helicopters need not apply. It’s also clear that the Air Force is most interested in learning about VTOL aircraft that “incorporate non-traditional electric or hybrid propulsion.”
The December RFI — Request for Information – VTOL and Associated Tech” (AFV_AP_RFI_Initial) — followed the revelation by Dr. Will Roper, assistant secretary of the Air Force for acquisition, technology and logistics, in a Sept. 16 speech to the Air Force Association (AFA) that the “flying car industry” is “an area we’re really excited to explore.” Roper made the remark as he discussed how the acquisition arm he leads was working with the Air Force’s new technology innovation agency AFWERX to “open the door to outsiders.”
Roper told reporters at the AFA conference that to “look into where commercial innovation is going in flying cars” was a “low-hanging opportunity” for the Air Force.
The Air Force has formed an integrated product team (IPT) to implement the project, dubbed “Agility Prime.” Led by the Program Executive Office for Air Force Mobility at Wright-Patterson Air Force Base in Dayton, Ohio, the IPT includes AFWERX and the Air Force Research Laboratory. The IPT is directed by veteran Air Force fighter jet test pilot Col. Nathan Diller, assistant director of aeronautics at the White House Office of Science and Technology Policy (OSTP) and Air Force advisor to the Strategic Capabilities Office (SCO) of the Pentagon.
“Initially, it’s just us making sure that we understand the market, understand the technology,” Diller said in an interview with Vertiflite. But as the Air Force explores how autonomous electric and hybrid electric VTOL aircraft might be used for military missions, the service also wants to assess whether it can help aircraft developers mature faster and generate data in early use cases to “accelerate the regulatory” process to get their designs certified for commercial use “by working closely with FAA,” he said.
Distributed Electric Propulsion, Wingborne Flight Preferred
The IPT’s mandate, as expressed in the RFI, is to explore “transformative” VTOL aircraft and “shape a strategy to collaborate with commercial partners in a way that accelerates development and fielding of the most promising vehicles, subsystems, and infrastructure based on likely success in the commercial market. As these systems mature towards certified commercial operations, the Air Force will position itself to be an early adopter, with a potential goal of procurement and fielding within three years.”
The February Open Call went into detail. “The core technologies of interest for this open call include emerging electric VTOL (eVTOL) and urban air mobility (UAM) aircraft, though alternatives will be considered,” the announcement said. “These aircraft may incorporate non-traditional electric or hybrid propulsion for manned or optionally manned missions, with onboard pilot, remote pilot, or autonomous control.”
The announcement added that “these transformational commercial vehicles are typically characterized by employment of distributed propulsion for vertical flight and potential use of a wing for horizontal flight, along with highly augmented flight control systems and high levels of automation or autonomy.”
That probably describes most of the aircraft being studied that are included in the 250+ that VFS is tracking on its World eVTOL Aircraft Directory (www.eVTOL.news/aircraft).
“While the USAF continues to investigate a broader set of vehicles for future industry engagement, the focus here is on vehicles with significant commercial market potential and planned performance and safety,” the Open Call announcement added.
The earlier RFI also specified that, “this effort is NOT [emphasis in the original] interested in smaller unmanned aerial systems” but wants information on concepts for manned aircraft of all weights or unmanned aircraft with a maximum gross takeoff weight greater than 1,320 lb (600 kg). That corresponds to military drone categories Group 4 and Group 5, which include unmanned aircraft the size of the Air Force’s armed MQ-9 Reaper and larger platforms. But the Air Force wants aircraft large enough to carry people no matter what the weight of the vehicle. Other language in the RFI indicates the Air Force is interested in aircraft for utility missions.
The RFI suggested self-flying and electric aircraft “could introduce game-changing capabilities for distributed logistics, sustainment, mass, and maneuver, with particular utility in civil and military disaster relief, medical evacuation, firefighting, installation and border security, search and rescue, and humanitarian operations.” It also said that the “Air Force intent would be to capitalize on the commercial investments already made in developing these aircraft, to help facilitate their rapid maturation, and to do so on a minimal and non-interference basis. The USAF would also hope to leverage future large-scale commercial production.”
“The RFI speaks to some of the use cases on logistics and disaster response,” Diller said. “Certainly, right now there are potential opportunities where we could do that at much lower cost and be more agile.”
Culture Clash Considerations
Most eVTOL developers have little or no experience working with the military. The Air Force hopes its offer to help win FAA safety certification, a key hurdle for eVTOL aircraft, may woo even those reluctant to do military work to collaborate.
“For potential partners developing flying vehicles, the USAF intends to hold a series of test and development campaigns tailored to the needs of each individual firm and offering use of DoD-unique resources,” such as test facilities and flight test ranges, to help developers “refine designs and drive systems towards their certification objectives with the Federal Aviation Administration,” the RFI said.
The February Open Call was an invitation to do just that for developers with aircraft ready to fly. The announcement said the Air Force would use a sole source contracting method called “Other Transaction Agreement for Prototype Projects,” or OTA-P, to fund tests.
“The government is requesting details regarding planned commercial vehicles and markets,” the Open Call said. “If those vehicles have a high likelihood of meeting the … [stated] specifications, the government will offer opportunities for collaborative test planning with the potential of offering test assets and expertise.”
Responses to the RFI are due March 1. Diller said that by early February, the Air Force had heard from about 30 companies, including both those developing their own aircraft and those developing related technologies. “We’ve also had a lot of conversations with investors,” Diller said. “To some degree they’ve reached out to us, and in some cases, we’ve reached out to them to understand if this strategy of partnering with commercial investment is actually a valid strategy. I would say there’s almost as many [investors] as companies we’ve spoken with.”
Many eVTOL developers have been secretive about their work (see “Lilium Goes Its Own Way,” Vertiflite, Jan/Feb 2020), and Diller said many companies have shied away from providing the level of information requested by the Air Force. The RFI and Open Call both asked for detailed data on the companies, their investors, the specifications of their aircraft and other technologies, and the status of and plans for their projects — information of that sort is usually found in closely held business plans written for potential investors. As a result, Diller said, rather than submit written responses as requested, “Many of the responses to the RFI have been requests to give direct briefings or phone calls to explain here’s what they have [and to say] they would like to have some interaction, trying to understand what the government could potentially offer.”
Agility Prime is part of a broader quest by the Defense Department to inject into defense acquisition some of the speed and innovation characteristic of civilian technology development of the sort embodied in tech products such as smartphones. In addition to its RFI for the new Air Force mobility program, Diller noted, AFWERX and AFRL have awarded large numbers of Small Business Innovation Research grants in the past year under a program called SBIR Open Topics. The program has awarded “more than 900 contracts worth a combined total of approximately $220 million,” according to the AFWERX web site (www.afwerx.af.mil/sbir.html).
“This is kind of a strategic effort to create that relationship with industry that draws in a lot of non-traditional companies that maybe haven’t worked with the Department of Defense,” Diller said.
Other Pentagon Interest
The Agility Prime initiative Diller leads isn’t the first time the Air Force or other arms of the Pentagon have shown interest in eVTOL and autonomous or semi-autonomous aircraft able to perform utility missions. The Marine Corps experimented with two unmanned Kaman K-MAX helicopters modified by Lockheed Martin for cargo delivery in Afghanistan in 2011–2013, and in May 2019 awarded Kaman Aerospace a contract to restore those CQ-24A aircraft to flight-ready status.
The Defense Innovation Unit (DIU), like AFWERX a quasi-venture capital organization created as part of the Pentagon campaign to rethink acquisition, awarded contracts in January 2017 to pioneering eVTOL companies Joby Aviation and Kitty Hawk to provide information on eVTOL aircraft whose “primary function is to transport one to four adult human passenger(s) or equivalent payload mass; with remote piloting required, with both autonomous and manual flight control desirable,” according to a description provided by DIU.
Andrew Musto, DIU deputy director for autonomous systems and a former Marine Corps AV-8B Harrier jump jet pilot, said the purpose of the contracts was to examine whether an unspecified military user might be able to use Joby’s or Kitty Hawk’s eVTOL designs “for a couple of specific military use cases.” He declined to identify any potential users or missions studied.
“We’re exploring general military utility of the commercial technology as the companies are developing it for general military use cases,” he explained. “We entered into Other Transaction Agreements with both Joby and Kitty Hawk back in 2017. We have since terminated the contract with Kitty Hawk, and Joby is the only one continuing to do work for the DOD under the Defense Innovation Unit.”
Joby Aviation, which has been flight testing an all-electric, five-seat, piloted aircraft that has six tilting propellers and a wing for forward flight, has received DIU contracts worth $12M, a DIU spokesperson said. DIU’s terminated contract with Kitty Hawk, which last year spun off its Cora eVTOL air taxi prototype to a joint venture with Boeing called Wisk, was valued at $1M. The two-passenger Cora is a separate lift-plus-cruise propulsion, winged aircraft with 12 small lift rotors for vertical flight and a single pusher propeller for forward cruise.
So far, DIU’s eVTOL exploration has been separate from the Agility Prime project. “We are talking with Agility Prime continually as they start to stand up their effort, but we are not formally taking part in Agility Prime at this moment,” Musto said.
Greg Bowles, head of government affairs for Joby Aviation, confirmed that Joby is working with some DIU personnel who witnessed a test flight of the Joby aircraft that was conducted last year. Joby’s work for the Defense Department has consisted entirely of sharing information about its aircraft and the company’s view of the market for eVTOLs.
“We’re spending a lot of time putting together detailed information to help them, but it’s all civil in nature,” Bowles said. “The knowledge that they’re getting is invaluable. It’s really early knowledge on electric and VTOL aircraft.”
Joby also responded to the AFWERX RFI “to remain in the loop on those activities,” Bowles said, but he emphasized that the company’s interest is purely in civil eVTOL uses. And the government is interested in similar personnel and cargo use of eVTOLs, he added.
“The US government is trying to make sure there is a robust UAM industry here in the US,” Bowles said. “I think they’ve got some thoughts about the importance of the significant civil market that is coming into existence and they would like to prove out utility for eVTOL.”
About the Author
Richard Whittle, author of The Dream Machine: The Untold History of the Notorious V-22 Osprey (Simon & Schuster, 2010) and Predator: The Secret Origins of the Drone Revolution (Henry Holt and Company, 2014), is a Research Associate at the Smithsonian National Air and Space Museum and a frequent contributor to Vertiflite.