Bright Sparks

This is particularly evident in the development history of fixed-wing aircraft.

Dramatic improvements in battery storage systems, realised in the late 20th and early 21st century, led to reinvigorated interest in electric engines across the aviation sector. Although small in scale when compared to conventional propulsion the presence of electric powerplants on fixed-wing aircraft is growing.

Leading the charge is Israeli-based Eviation. Founded in 2015 on a commitment to bring electric aircraft to the masses, the organisation is guided by a team of experienced entrepreneurs, pilots and engineers. As such, the relatively young Eviation boasts a wealth of experience in leading successful technology companies as well as delivering innovative technology programs.

Omer Bar-Yohay is co-founder and CEO of Eviation. Speaking with Australian Aviation he said electrification is overdue in the aviation sector with environmental, efficiency and cost pressures creating real demand for alternative propulsion systems.

“The aviation sector is projected to consume one-fourth of the world’s carbon budget by 2050 – and is currently lagging behind its counterparts on the ground in the race to electrify,” Bar-Yohay said in December.

“This is supported by the International Air Transport Association which recently reported that oil prices, which traditionally account for 30 per cent of an airline’s costs, have risen to 52 per cent since June 2017.

“It makes economic and environmental sense to disrupt the current aviation market, but it also is technologically feasible. Today’s battery capabilities are already able to power flights of 500 miles or less, a distance encompassing half of the world’s 4.5 billion flights annually.”

Electric inspiration

Eviation’s Omer Bar-Yohay has a long association with aviation. In more than a decade serving in Israel’s Defence Force, he became highly experienced in aviation management and honed his skills at leading multi-disciplinary teams to achieve outcomes, often in high-pressure or time-sensitive situations.

Today he is a member of NASA’s On-Demand Mobility Working Group. Additionally Bar-Yohay sits on the e-Aviation Committee for the General Aviation Manufacturers’ Association, giving him a wealth of insight into the development trends of electric aircraft.

Bar-Yohay founded Eviation with the goal of changing the way people move regionally; by creating an aircraft to enable an affordable, fast and sustainable option for commuters.

This, he says, relies on a “strong integration with on-demand ground transport solutions” aimed to deliver a technologically advanced yet simple air-travel solution. Bar-Yohay elaborates: “Our electric aircraft will change how people think about travelling and commuting. Our goal is to let someone take a 650-mile trip for roughly the price of a bus ride.”

If realised, this ambitious goal will no doubt cause significant disruption, not only to the regional aviation market but also to ground transportation networks. And the regional aviation market is by no means a small beast, with Bar-Yohay adding, “the five to 10-year outlook shows demand for about 1,000-3,000 new regional aircraft every year.”

‘Our electric aircraft will change how people think’
OMER BAR-YOHAY

Eviation’s ambitions are equalled only by the potential of electric aircraft to finally deliver a variety of benefits in the regional and commuter markets. Such benefits range from reduced carbon emissions to improvements in fuselage aerodynamic efficiency and reduced operating costs, leading to higher returns for operators.

Bar-Yohay explains: “Using electricity instead of fuel creates a very cheap per-seat per-mile solution, because electricity is cheaper than jet fuel. An electric plane also requires less maintenance. The maintenance of jet engines alone accounts for one-third the cost of travel for consumers, which is significant. When you use a battery instead of a complex combustion engine, maintenance gets a lot simpler.”

Since day one, Eviation’s approach has been to design a new aircraft based on electric propulsion. Rather than attempting to retrofit an existing aircraft, Eviation’s blank-slate approach allows engineers to create an aerodynamically effective and efficient aircraft which complements the electric powerplant.

“The end result is Eviation’s cost per mile will be comparable to a bus ticket at $.1 per seat/mile. Eviation’s model, therefore, capitalises on massive fuel and maintenance cost savings enabled by electric flight,” Bar-Yohay predicts.

Road to electrify

With electric propulsion offering such potential, it is little wonder casual observers might ask why it isn’t more widespread today. The answer lies not in an industry-wide disinterest in utilising electric powerplants, but rather the difficulties of storing electricity in sufficient quantities to make such propulsion viable.

While successfully applied to the behemoth airships of yesteryear whose helium or hydrogen fuel cells were able to absorb the weight of such large scale electrical storage, fixed-wing aircraft don’t have the luxury of a lifting gas to offset the weight of batteries.

In fact it wasn’t until the 1970s that battery storage became efficient enough to allow Austria’s HB-3 Brditschka glider to carry an electric motor, offering electrically-powered flight. The aircraft was successful in overcoming the fixed-wing barrier, though the technology remained something of a novelty for the rest of the decade.

It took 20 years for NASA to boost the development of electric powered propulsion achieved through its pioneering Pathfinder program. During the 1990s, light aircraft producers started taking note, with several variants available by the end of the 20th century.

However in order to realise the widespread use of electric aircraft, battery storage had to reach its potential. This revolution took off during the early years of the 21st century, and shows no signs of abating.

The move from lead acid to nickel and now lithium-ion batteries has seen storage volumes jump to levels unheard of in the 19th or 20th century. In fact, energy density in lithium-Ion batteries has soared since the technology was first commercialised in the 1990s, while costs have plummeted thanks largely to the wide scale acceptance and ongoing development of the technology.

Such improvement in battery storage has led to its commercial application across a variety of consumer fields – from mobile phones to drones and even large road vehicles. This customer acceptance of battery power is a fact that Bar-Yohay is well aware of, commenting: “The rise of companies like Tesla, and the major auto manufacturers’ rush to roll out their own electric vehicles tells us that people are increasingly comfortable with electric transportation.”

Enter Alice

Thanks to a boom in technological development, widespread demand for operating cost reductions and a growing need to protect the environment, the industry is ripe for electric aircraft disruption.

Alice is Eviation’s solution to the global need to electrify. A pressurised regional commuter aircraft, Alice will carry nine passengers and two crew at altitudes between 3,048m and 10,000m while being capable of speeds in excess of 240 knots (444km/h).

The 12.2m-long aircraft is powered by a 900kWh Kokam lithium-ion battery. It offers a maximum takeoff weight of 6,350kg and provides a range of more 1,000km. For an electric aircraft these are impressive figures, yet Bar-Yohay says the affordability and environmentally friendly aspects of Alice are perhaps the most important features for customers.

To meet its promised performance, Alice is propelled by three Hartzell Propellers. These electric powerplants are mounted with blades facing aft, with one fixed to each wing, and a third unit in the tail cowling. The unconventional layout gives the aircraft a distinctive profile.

“This is an innovative system of new propellers, designed to meet the unique needs of the first-in-kind aircraft,” Bar-Yohay explains. “The design and manufacture of the propeller systems underway will utilize Hartzell’s 5-blade carbon fibre blades and Bantam hub series to provide the optimal combination of reduced weight and maximum performance.”

Additionally, while some electric aircraft are derivatives of conventionally-powered types, the engineers at Eviation opted to design a totally new airframe. This course has allowed the aircraft to be optimised, delivering aerodynamic enhancements that will aid the electric powerplants in their quest to deliver efficient and cost-effective flight.

Such an approach has allowed Eviation to minimise the weight of the airframe, allowing maximum weight to be allocated to the battery. Bar-Yohay says this has led to a “highly optimised aircraft that can fly further on one charge”.

Looking ahead

As growing fuel costs put price pressures on regional and commuter operators, as well as the inevitable global shift towards renewables, electric powered aircraft are sure to become more common at airfields across the globe.

Due to take flight later this year, Alice is well positioned to spearhead the realisation of Eviation’s electric dream. With comparably low operating costs, the aircraft is positioned to challenge the status quo in the commuter and small regional market.

However the potential doesn’t stop there, with Bar-Yohay saying this aircraft is intended for “everyone”, believing the benefits it offers will appeal across a range of operators – from regional airlines to air taxis, private users to commuter services.

“Price is the main benefit of electric aircraft for consumers, by far. By lowering the price of regional air travel, consumers also get the benefits of easier, cheaper, faster travel between places that would have taken them hours to get to by car. For instance, it might change where they decide to live and work,” Bar-Yohay predicts.

So as the team at Eviation prepare Alice for its maiden flight, the future of electric air transport looks brighter than ever. For Alice, the sky truly is the limit.

‘A highly optimised aircraft that can fly further on one charge.’
OMER BAR-YOHAY