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Regional Turboprops Showing Potential for Hydrogen Power in the Near Future

Avionics International highlights research and development activity happening at two companies, Universal Hydrogen and ZeroAvia that could enable the entry into service for a hydrogen powered regional turboprop aircraft in the near future.

As the global air transportation industry continues to be transformed by the impact of the COVID-19 coronavirus pandemic, flying quietly under the radar are a series of initiatives and companies working to make hydrogen-powered regional turboprop aircraft a reality by the mid 2020s.

Here, Avionics International highlights research and development activity happening at two companies, Universal Hydrogen and ZeroAvia that could enable the entry into service for a hydrogen powered regional turboprop aircraft in the near future.

Universal Hydrogen

Distribution of hydrogen power to regional turboprop aircraft could become a reality by the mid 2020s, according to a disruptive new California-based green startup that is already talking to airlines and airplane manufacturers about their concept. Universal Hydrogen CEO Paul Eremenko and COO Jason Chua explained during a recent interview how they envision using the global intermodal freight network to eliminate the need for infrastructure and provide hydrogen power for passenger carrying regional airline flights in the near future during a recent interview.

The company has multiple patents pending associated with its invention of hydrogen storage pods capable of generating enough power to initially enable flight operations on short haul regional airline flights.

Rather than trying to develop the infrastructure required to store, develop and distribute hydrogen, their capsule converts hydrogen to dry freight to enable transportation from the point of consumption to airports where aircraft need refueling. Their design takes advantage of the concept of intermodal freight, which uses containers that can be transported through a variety of vehicles including ships, semi-trailer trucks, and trains. (Universal Hydrogen)

“A really important point to just make very clear is that we're not an airplane company and we do not aspire to be an airplane company. We are a hydrogen logistics company and we would like to serve as many different aviation market segments with hydrogen as possible,” Eremenko said.

According to an information sheet provided by the startup, the modular capsule is “2X more weight-efficient than traditional hydrogen storage” and is part of a “retrofit package for existing regional aircraft using mature electric motor and fuel cell technologies.” De Havilland’s Canada Dash-8 Q-300 and the ATR-42 are some of the regional aircraft types that have already had discussions with Eremenko, Chua and their other co-founders – a team of former UTC executives who left the company after the Raytheon merger.

Rather than trying to develop the infrastructure required to store, develop and distribute hydrogen, their capsule converts hydrogen to dry freight to enable transportation from the point of consumption to airports where aircraft need refueling. Their design takes advantage of the concept of intermodal freight, which uses containers that can be transported through a variety of vehicles including ships, semi-trailer trucks, and trains.

Entry into service within the next five years is envisioned by Eremenko and his co-founders with a three phased process. Over the next year, under Phase A the hydrogen capsules will be developed and tested at full-scale to include an end-to-end demonstration of their intermodal power distribution concept from the point of production to an “aircraft-scale ground testbed for fuel cell powertrain.”

Phase B includes achievement of air transport certification for their capsules prior to Phase C: “mass industrialization of the capsules and FAA certification of a hydrogen-powered regional turboprop carrying 40 passengers with up to 500 nm range,” the startup notes on their information sheet.

“Initially we will focus on the regional turboprop aircraft segment. We think that it's a good proof point for anything bigger. Eventually we want to be able to tackle the single aisle market because that is where the majority of the world's passenger miles are flown, and that's where the majority of fuel burn and carbon emissions happen,” Chua said

The company is already taking major strides toward making their vision a reality too. After emerging from stealth in late August, Universal Hydrogen has already established a partnership with Redmond, Washington-based magniX to supply the electric propulsion system as part of a retrofit conversion kit for the De Havilland Canada DHC8-Q300.

The retrofit conversion kit being developed by Universal Hydrogen for the Dash 8 is part of their goal to promote near term adoption of hydrogen power for commercial aircraft. Under the partnership with magniX, they have now secured the motors, inverters, and motor controllers as part of their full hydrogen fuel cell powertrain.

Universal Hydrogen’s Dash-8 rendering shows the use of six capsules required, or three modules of two capsules each. The Dash-8 will require 2 megaWatt power motors. (Universal Hydrogen)

“magniX is responsible for the 2MW-class electric propulsion systems,” magniX CEO Roei Ganzarski told Avionics.

Ganzarski said the use of hydrogen power as compared to a lithium-ion battery can enable the use of the cleaner energy source on larger aircraft.

“magniX provides the electric propulsion systems that take electricity as input, and provide propeller torque as output. From our propulsion perspective, there is no difference between the source of the electricity. With that said, the hydrogen fuel cell technology is enabling the electrification of much larger aircraft like the Dash-8 or ATR42 which is very exciting as this opens up a much larger operational envelope,” Ganzarski said.

ZeroAvia

On Sept. 24, ZeroAvia – a Silicon Valley-based startup – completed the first hydrogen-fueled commercial-grade aircraft flight using their Piper M-class six-seater turboprop.

The UK government has funded ZeroAvia’s hydrogen-fueled program through their Aerospace Technology Institute (ATI) Program. This flight was also part of the HyFlyer project, which aims to decarbonize medium range small passenger aircraft. Their flight took place at the company's research and development facility in Cranfield, England, with the Piper M-class completing taxi, takeoff, a full pattern circuit, and landing.

"Developing aircraft that create less pollution will help the UK make significant headway in achieving net-zero carbon emissions by 2050,” Nadhim Zahawi, UK business and industry minister, said in a statement. “Backed by Government funding, this flight is another exciting milestone in ZeroAvia's project. It shows that technologies to clean up air travel are now at our fingertips - with enormous potential to build back better and drive clean economic growth in the UK."

In July ZeroAvia completed its first phase of test flights for a hydrogen-fueled commercial-grade aircraft. The more than 10 test flights completed used a Piper Malibu Mirage turboprop modified with a 300-kilowatt (kW) battery electric power system along with a customized cockpit display and computer.

ZeroAvia CEO Val Miftakhov told Avionics that the goal with that first round of flight testing was to match the performance of the aircraft’s stock engine, a six cylinder Lycoming 540-AE2A with a 350 horsepower rating –– or the equivalence of 260 kW.

“Cranfield is a sea level airport, and we were at 1,000 feet [mean sea level] MSL, in a pattern, so these are mostly sea level numbers. We recorded the most economic cruise from the flight occurring at 2,000-RPM prop speed, 90 kts indicated and that was with 75 kW of consumption. That works out to about 800 or so watt hours per nautical mile, which is pretty good, given that it’s comparable with what my Tesla Model S does at that speed,” Miftakhov said.

ZeroAvia and the European Marine Energy Centre (EMEC) have also created at Hydrogen Airport Refueling Ecosystem (HARE) at Cranfield Airport. The hydrogen production and refueling facility is also a first and offers a microcosm of what a hydrogen airport ecosystem will look like.

ZeroAvia showed the modifications for its first hydrogen-powered flight. (ZeroAvia)

“Instead of getting electricity from the battery we get it from the hydrogen fuel cell system, which takes hydrogen from the tanks, combines it with oxygen from the air, and produces electricity,” Mifthakhov said.

Project HyFlyer’s ultimate goal is a 300-nautical mile flight in the hydrogen-powered Mirage taking off from the Orkney Islands in Scotland. Miftakhov believes his team will enable the development of a certifiable zero emissions hydrogen-powered turboprop by 2023.

While the 2023 goal is a 19-passenger Twin Otter capable of 500-mile regional flights, their next goal will target larger regional turboprops like Bombardier’s Dash-8 or the ATR 500 series by the end of the decade. Mifthakov said the team believes it can achieve operating costs that are half of what are required for a jet fuel powered Twin Otter.