Uber Partnering with Aurora on Urban eVTOL Network

Ride-sharing service Uber officially kicked off plans for an urban electric vertical takeoff and landing (eVTOL) network at an industry “Elevate” summit in April. Uber plans to launch demonstration networks in Dallas and Dubai by 2020 and has signed technology agreements with Bell, Embraer, Aurora, Pipistrel and Mooney to develop air vehicles and related technologies. It said it will welcome other manufacturers into the network as well. Uber is also partnering with ChargePoint to develop network vehicle charger stations. The vehicles will have stringent requirements for safety, noise and emissions; be expected to have a range of at least 60 miles and a maximum speed of 150 mph; be durable enough to fly 2,000 hours per year; and have direct operating costs of $1.32 per passenger mile or less, which Uber points out is less than the variable cost of car ownership.

Uber first made the case for urban vertical flight last year in a widely distributed white paper titled “Fast-Forwarding to the Future of On-demand Urban Air Transportation.” The widespread deployment of such a system, according to Uber, will reduce congestion, save time and involve lowerinfrastructure costs than ground-based transportation. “This isn't going to be easy,” acknowledged Uber chief product officer Jeff Holden, “but it can be done sooner rather than later.”

The key to getting the network in place is “radically changing the type of aircraft we're manufacturing here and doing it at mass scale,” Holden said.  Those aircraft would incorporate distributed electric power (DEP) propulsion and fly-by-wire controls to improve speed, efficiency, redundancy, reliability and safety while reducing noise and emissions.

“Helicopters won't work because of noise, cost and energy efficiency and speed limitations. Combustion engines are only 23-percent efficient, while electric motors are 92-percent efficient. A fixed-wing design with DEP gives you a 10-fold efficiency improvement over a rotorcraft with a combustion engine. Helicopters also have single points of failure and you need to maintain them extremely carefully and do teardowns frequently, and that translates into high operating costs,” he said. The aircraft would initially be piloted, then optionally piloted and eventually be able to fly throughout the network fully autonomously.

Building an Urban Network

Holden said working with NASA and the FAA will be critical in developing the network. Uber is partnering with the agencies to develop and test scheduling and separation methods to ensure safe flight. “We're going to have a lot of these aircraft in the air, particularly when you combine them with drones. NASA is going to be a tremendous partner to make this a reality.”

Uber has hired NASA veteran Mark Moore as director of aviation engineering. Moore, who spent 32 years at NASA concentrating mainly on electric flight, said the network is going to require the air vehicles to have “precise digital datalinks” on board for real-time deconfliction data to be communicated among vehicles. The amount of deconfliction required could be substantial. Holden said Uber's modeling suggests a demand for up to 200,000 air trips per day in the demonstration cities.

Dr. Jaiwon Shin, associate administrator for the Aeronautics Research Mission Directorate at NASA, said a likely urban ATC model for the network will follow along the lines of the UTM (Unmanned Aerial Systems Traffic Management) currently being developed, but that deployment of the Elevate network will test government regulators' ability to work with industry expeditiously and that industry needs to be mindful of aviation safety requirements. “The FAA is learning that it needs to move much faster—at the speed of innovation,” he said.

In Dallas, the Elevate network will use the existing vertiport next to the Convention Center and three more to be built by the Perot family's Hillwood Properties real-estate arm. Aside from the fact that the FAA's rotorcraft directorate is based in nearby Fort Worth, Ross Perot, Jr. noted that it is an ideal location for a launch site: the greater Dallas-Fort Worth area has a population of 7.5 million and it's growing by one million every seven years, 130,000 every year. Perot also noted the metro area has $21 billion worth of new construction under way, second only nationwide to New York City. The ground transportation network is vast and notoriously congested.

The three new vertiports are slated for Frisco Station, next to the American Airlines Center in downtown Dallas, and in downtown Fort Worth. Perot also noted that there is plenty of capacity at the Alliance industrial airport for aircraft manufacturing and pilot training and that the low airspace above the Burlington Northern Sante Fe rail lines that weave through Dallas would make convenient vertipaths.

Perot's firm has ties to Dubai, the second demonstration market. The Dubai Road and Transport Authority is already funding eVTOL demand studies for a better understanding of pricing and optimization in that market, Uber's Holden said. Uber's goal is to have flights ready to go in Dubai in time for the World Expo there, which opens on Oct. 20, 2020.

A Glimpse of the Future

At the Elevate summit, a few OEMs shared their vision for vehicles while some brought videos of scaled vehicles that hav recently flown. Bell Helicopter's Scott Drennan, director of engineering innovation, said his company's design would be robust enough to fly 2,000 hours per year; be “modular, adaptable and scalable”; use a variety of powerplants; have both civil passenger and military logistics applications; and likely be certified in the powered-lift category (FAR 21.17B).

In April, Aurora Flight Sciences flew a quarter-scale prototype based on the XV-24 it is developing for the military. The Aurora design has separate propulsion systems for hover and cruise and uses eight distributed lift rotors mounted on booms and one main aft-mounted propulsor along with a main wing and three lifting surfaces. Once the aircraft transitions past the stall speed (40 mph) in cruise flight, the lift rotors shut down.

Airbus A³ (the company's Silicon Valley arm) said subscale versions of the Vahana tiltwing eVTOL have already flown and that a full-scale version will fly by year-end. The goal is for production aircraft to be fully autonomous and equipped with low-altitude ballistic recovery system parachutes.

Carter Aviation Technologies has partnered with Mooney to develop a four- to six-seat vehicle that uses Carter's slowed-rotor compound design and cruises at 175 mph. Carter CEO Jay Carter points out that the high-inertia main rotor is always turning and in effect functions as a main parachute while providing directional control all the way down to the ground in the event of an emergency.

On April 20, German start-up Lilium conducted a successful unmanned flight of the two-seat Eagle prototype eVTOL jet. The design features 36 low-vibration electric jet engines mounted to wings via 12 moveable flaps, which are pointed downward on takeoff and landing to provide vertical lift, but gradually transition to the horizontal to provide forward thrust. The engines are shielded to protect each other from the impact of uncontained failure; they have a small fan diameter and limited drag; and feature a simple design of two bearings, one shaft, and simple rotors. The design of the aircraft makes it maneuverable during transition flight, a key advantage in an urban environment, said Lilium CEO Daniel Wiegand. “We can fly curves during climb and descent,” he said. The aircraft has a range of about 186 statute miles and top speed of 186 mph.

However, amidst all the aircraft designs and grand plans discussed at the Elevate summit came this caution from Pipistrel CEO Ivo Boscarol, whose Slovenia-based company has been manufacturing electrically powered aircraft since 2007: “People are afraid of electric flight. We must focus on the marketing, how to promote electric flight in a way that people do not get scared.” Along those lines, Pipestrel's director of R&D, Tine Tomazic, noted that more people have flown in space than in electric aircraft.