Graham Warwick Beta’s Alia eVTOL hews as close to a conventional fixed-wing aircraft as possible.
Graham Warwick
For Beta Technologies, the most direct path to certifying an entirely new class of aircraft is to keep it simple. The Vermont startup’s strategy is to focus on the key innovation and keep the rest of the aircraft as conventional as possible.
Beta is developing the Alia electric vertical-takeoff-and-landing (eVTOL) aircraft. The key innovation is distributed electric propulsion. But the company has designed the Alia to spend as much of its time as possible flying like a fixed-wing aircraft.
There are no articulating nacelles, no variable-pitch rotors, no gearboxes, no liquid cooling. There are multiple redundant electric motors and battery packs in a lift-plus-cruise configuration designed to combine safe and efficient vertical and horizontal flight.
There are no advanced flight control laws to make the machine easier to fly. A session in the simulator in Beta’s Washington office makes clear that the Alia is designed to be flown by a professional pilot. It is a decision intended to simplify the route to certification.
“The number of requirements that you impose on an aircraft will define your path to certification. Because every one has to be paired with a means of compliance, a test and an objective assessment of the failure mode effects and criticality analysis,” says Beta Founder and CEO Kyle Clark.
“So the first step in simplicity is minimizing the requirements,” he says. “If we have a flight controller and say, ‘No longer is that flight controller required to have airspeed or angle of attack,’ those are two things you don’t have to test or write a means of compliance for.”
Keeping it simple is central to Beta’s strategy for FAA certification. “The FAA wants a win here,” Clark says. “They’ve done a great job of laying the groundwork . . . [and have] been very helpful in ensuring we get clarity. Because indecision, in my opinion, is the biggest impediment to our progress.
“It doesn’t mean we get the answer that we want, but it is clear,” Clark continues. “And I believe what they appreciate about our design is that there’s simply less to do.”
Where Beta’s closest eVTOL competitors all use tilting mechanisms to vector thrust, the Alia has four lift propellors for vertical flight and a pusher prop for wingborne cruise. Shaped like blender blades, the fixed-pitch lift props are stopped in forward flight, aligned fore and aft with the airflow to minimize drag.
To provide the commercial aviation level of safety required, each of the Alia’s four lift props is powered by two motors, each of them with dual windings, providing fourfold redundancy. A dual-redundant motor drives the pusher propeller. Up to five independent battery packs power the props.
Outside of those features, the Alia is resolutely conventional, with a long-span wing for low cruise drag and redundant ailerons, elevators and rudders for control in forward flight. In place of retractable gear, the aircraft has “skwheels”—landing skids that incorporate wheels in a low-drag arrangement.
Unlike the eVTOL prototypes, the Alia has been flown piloted from the outset. Credit: Beta Technologies
“The No. 1 thing is to take the requirements out,” Clark says. “And if you leave it on the ground, it doesn’t exist. You don’t have to certify it, you don’t carry it around, you don’t have to pay for it, you don’t have to design the system for it. It’s just intensely practical to not put it on the airplane.”
Simplicity must be balanced with capability. Here the fact that all of Beta’s employees are pilots, or becoming pilots, plays a role. “The trick is to find the balance,” Clark says. “And if you put somebody in the cockpit every day, they start to learn what’s really important, not what they think is important.”
The strategy of simplicity threads through Beta’s operation from technology to market to funding. Unlike its leading rivals, the startup does not plan to operate its own eVTOLs but instead to manufacture, sell and support them. Beta already has purchase agreements with Blade, UPS and United Therapeutics (see chart).
The startup also sets itself apart from its direct competitors by expecting that cargo will be the first eVTOL application to scale up, because securing customer and public acceptance will be more straightforward.
Beta has already raised $511 million in private funding and, unlike its rivals, the company is not planning to go public through a merger with a special-purpose acquisition company. Becoming a public company at this stage would unnecessarily complicate Beta’s business operations, Clark says.
Instead, the startup has carefully selected private investors directly aligned with its mission and with a clear understanding of the complexity of certifying even a simple eVTOL. The $368 million funding round in May was led by Fidelity Investments, along with Amazon’s Climate Pledge Fund and Redbird Capital. “We elected to take in these investors. They did not have ulterior motives beyond our mission,” he says.
Beta’s strategy has been shaped by Clark’s experience developing highly reliable power electronics for national laboratories and companies such as Raytheon and Tesla—“people who say, ‘it’s simply not tolerable for this not to work properly,’” he says.
The company’s approach “is the result of having built many hundred kilowatts of power systems and recognizing that it is not trivial, especially when you are trying to put [a new technology] into an environment where it has never been before,” Clark notes.
“The only way that it ended up working there, and the only way I believe it is going to work in aviation, is to identify the most valuable feature of the technology you are introducing,” he says. “And in our case, it is the fact you are taking all the fuel out of the aircraft.”
Beta’s goal is to exploit the benefits of electric propulsion—simplicity, fuel elimination, energy savings and maintenance reduction—and the vertical flight capability of distributed propulsion. The Alia is designed to fly point to point with the ability to take off and land on a 50 X 50-ft. pad.
A variable-pitch pusher prop provides propulsion in wingborne forward flight. Credit: Beta Technologies
With a 50-ft. wingspan, the 7,000-lb.-gross-weight aircraft is designed to carry a pilot and five passengers or 200 ft.3 of cargo in a capacious fuselage. The performance target is to fly a 600-lb. payload 250 nm at 145 mph—or 1,500 lb. 200 nm—on a single charge, with recharging taking about an hour.
The Alia has a 330-kWh battery system under the fuselage. In testing to date, the aircraft has flown 205 nm in fixed-wing-only mode with three of the five battery packs installed. “It is a happy, happy CTOL [conventional--takeoff-and-landing] aircraft,” says Clark. “It’s burning 100 kW doing 105 kt. That’s a remarkably efficient aircraft at this weight.”
The eVTOL is designed for efficient cruise flight to conserve battery energy, and the power-hungry vertical takeoff and landing phases are minimized. “The hover and transition time at the beginning and the end total between them about 40 sec.,” he points out. “You’re only spending 40 sec. of a 2.5-hr. mission in VTOL.
“One of our best missions is to take off vertically and land like an airplane, or vice versa, because you get the value of VTOL with the range boost of hitting one end as a CTOL,” Clark says. Blade CEO Rob Wiesenthal cites the ability to take off vertically from a helipad in Manhattan and land conventionally at John F. Kennedy International Airport as one of the key reasons he selected the Alia.
Beta has built two piloted engineering prototypes of the Alia. The company started testing in February 2020 with tethered hover flights at its base in Burlington, Vermont, but then the airport was closed in March 2020 because of the COVID-19 pandemic. In June 2020, the prototype was airlifted by helicopter across Lake Champlain to Plattsburgh International Airport in New York.
“We were going to do a bunch more hover testing before we went to fixed-wing,” he says. But after the Burlington airport was shut down, “we said, ‘let’s bring the fixed-wing testing over to Plattsburgh.’ Then Plattsburgh was shutting down to resurface their runway.” So after a few hundred hours of fixed-wing flights, the prototype was flown back to Burlington this July.
“We’ve done a lot of CTOL flying. We have plenty of energy in the bank to get to those ranges,” Clark asserts. “And we are hell-bent on completing all our pre-FAA testing to make sure that, aerodynamically, the aircraft does everything we expect it to.” The company has now restarted hover testing at Burlington. “We’re getting back into gearing up for transition testing on the manned version.”
Beta has completed hundreds of transition tests using subscale unmanned models. “Every day we’re doing transition testing on the unmanned versions and evaluating the corner cases. And we have high-fidelity simulations in the iron bird,” he says.
“One of the coolest tools we have is a rolling wind tunnel. We put the transition props on that and bring it down the runway at 100-plus kt. with those running on top of a 20,000-lb. truck to evaluate all the different inflow angles to the lift props.”
Beta also is still using its original Ava XC eVTOL demonstrator as a test asset. This is a modified kitplane fitted with four tilting pairs of coaxial variable-pitch rotors. “We use it as a flight controller test platform, for the battery management system and the fly-by-wire system,” Clark says.
The Alia is now fitted with wheeled-skid landing gear for ground maneuverability. Credit: Beta Technologies
The Ava has provided Beta with valuable insight into how to shield the electronic systems against electromagnetic interference from the high-power, high-frequency electric motors. “Your shielding has to be robust to failures. So that airplane and the iron bird are some of our best test assets,” he says.
The two Alia prototypes are nonconforming. The aerodynamics are what Beta plans to certify, but the airframe structure is not representative of the production vehicle. The first conforming prototype is planned to fly in 2022, and Beta is targeting FAA Part 23 certification by the end of 2024.
Beta is not as vertically integrated as some of its competitors. “We’re doing everything that is enabling internally—so the motors, inverters, batteries, flight controls, and the overall aircraft configuration and integration,” Clark says. The startup is going outside for the rest.
“This is another one of our secrets to getting through certification—there are already smart people that know how to build actuators and structure, propellers, interiors and avionics,” he says. “We’ve chosen to be the best propulsion company in the world. Copper comes in the door, and motors go out.”
If simplicity is a Beta strategy, then so is partnering. “If you choose not to include something on your airplane, it makes it cheaper, it will take less time. It’s a pretty fundamental truth,” he says. “And the parallel to that is that partnering with the best in the world for those elements that are not enabling electric propulsion is the right way to keep our promises to our customers.”
Beta’s customer base covers three key eVTOL use cases: urban air mobility, express logistics and medical transport. Blade plans to add the Alia to its on-demand helicopter service; package carrier UPS will operate the eVTOL as a small regional feeder; and United Therapeutics will use the aircraft to rush refurbished and manufactured organs to hospitals for transplants.
“In my opinion, cargo and logistics will unquestionably be adopted at a faster rate than passenger and other similar missions,” Clark says. He expects there to be less emotion associated with customer and public acceptance of eVTOL cargo operations.
This also applies to installing the infrastructure required to enable eVTOL operations. Echoing Tesla’s approach to introducing electric cars, Beta is already deploying its own charging stations at airports and hospitals across the U.S. to support its aircraft.
“We’ve been putting in a lot of recharging systems, both on- and off-airport. And the friction associated with putting in a charging station where you typically bring in cargo and logistics is way lower than in areas where people live,” he says.
The charging stations are an integral part of Beta’s business plan. While its eVTOL rivals are partnering with real-estate developers on infrastructure, “We have hundreds of permits underway. We are cementing the ground and putting power out to airplanes,” Clark says. Beta has infrastructure built or permitted at over 50 sites and expects to reach a deployment rate of two a week.
One product is an off-airport charging station, an “airport in a box” built from shipping containers that includes an elevated landing deck, crew rest and flight planning rooms, as well as chargers for aircraft and vehicles. “We have a number of those deployed and are putting more into hospitals,” he says.
Other charging stations in development include an on-airport dispenser. This is a UL 1741-certified product designed to connect to the electric grid and to safely trip offline in the event of supply perturbations. Beta is also developing a mobile system that resembles an airport fueling truck.
“The product vision for the charging systems is fundamental to the success of the aircraft,” Clark says. And in addition to deploying charging stations to support the Alia, “we have a couple of partnerships with other manufacturers, and we have their aircraft here now, quietly working,” he adds.
