Electric flight takes off

In the heart of British Columbia, Canada, the unmistakable sound of a de Havilland Beaver fills the air. This iconic aircraft, a single-pilot, seven-passenger piston plane, has been a symbol of Canadian aviation for decades. First introduced in 1947, it has seen over 1,600 units manufactured before production ceased in 1967.

Today, more than half a century later, the Beaver still soars through the skies, primarily on short flights, providing vital access to remote and disconnected areas of Canada. 

Some small regional airlines in Canada and the United States have made the de Havilland Beaver the backbone of their fleets. However, one of these carriers is now taking a giant leap into the future and putting the De Havilland Beaver back at the forefront of cutting edge aviation technology.

The Electric Beaver Takes Flight

Harbour Air, a regional airline based in British Columbia, Canada, with a mission that could revolutionise the aviation industry worldwide. Harbour Air is determined to retrofit its entire fleet of de Havilland Beavers with 100% electric-powered engines, aiming to become the world’s first fully zero-carbon airline.

Erica Holtz, Harbour Air’s Engineering and Quality Manager, explains the airline’s vision, rooted in a commitment to sustainability. Founder Greg McDougal, who owned the airline until two years ago, was a staunch advocate for innovation and reducing the airline’s carbon footprint. In 2010, they became the first carbon-neutral airline through a carbon offset program. But McDougal wanted more—they sought to electrify their fleet and prove that electric aviation was not only possible but commercially viable.

In their quest for electric propulsion technology, Harbour Air crossed paths with MagniX, an engine company based in Washington, USA. Miguel Marmol, MagniX’s Vice President of Engineering, outlines the company’s journey from its inception in 2005 as a research and development organisation focused on electric propulsion. They had an eye for the aerospace industry, recognising the potential of electric technology in an industry where weight is at a premium.

The partnership between MagniX and Harbour Air was forged, and their mission was clear: retrofit a de Havilland Beaver with an electric power unit. This endeavour posed its share of challenges, as the Beaver was not designed for electric propulsion, and MagniX was not initially an aviation company. 

Retrofitting the Beaver 

The De Havilland Beaver runs off a Prat and Whitney Wasp Engine. Holtz explains how when they put in the MagniX engine they had to lower the kilowatts to match the Pratt and whitney engine as close as possible. “So what we did with that was we took off the our 985 engine, basically everything firewall forward all the fuel systems anything related to the engine system, and then look to install the MagniX 500, which is capable of 500 kilowatts, but we rated it down to 338 kilowatts, which is equivalent to 450 horse because we didn’t want to change the flight or performance characteristics of the aircraft that wasn’t their intent. Our intent was to do a straight up propulsion swap and evaluate the novel technology and see how that could work on this airframe.”

Surprisingly, even after turning down the kilowatt output, the electric engine outperformed expectations, offering a 15% efficiency boost, partly due to the Beaver’s outdated propeller. Additionally, the MagniX engine’s lightweight design reduced the aircraft’s overall weight, contributing to improved aerodynamics after they were able to change out the nose of plane due to less cooling requirements.

Holtz explains, “The efficiency of these engines is so poor 80% of the power is actually being rejected in heat and so you have to cool the engine quite significantly. So there’s a lot of that frontal area that is just allowing air to come in to cool the engine, which also slows down and creates drag on the aircraft. So being able to put a pointy nose on it, we got a significant improvement in the aerodynamic performance of the aircraft.”

This transition from a traditional engine to an electric power unit also had another advantage—no change in the aircraft’s weight during flight, a significant departure from traditional planes where fuel burn affects load distribution.

The MagniX power unit is also designed to provide plenty of redundancy in case something fails while the plane is flying. “So the MagniX 650 has four inverters. So for devices that take the high voltage DC, turn it into alternating current to drive the motor, and the motor itself is split into four sections inside of the motor. So you could lose one inverter or have a short circuit and one of the motor phases or some other problem like that, and the engine will still continue running at at least three quarters percent power.” says Marmol.

Future Improvements

The eBeaver, as it’s known, is still being iterated upon to provide further improvements. One of the main ones is finding the best way to store the heavy batteries required, to provide optimal balance while also keeping all seven passenger seats.

“So we’re trying to use that space as efficiently as possible. And because these modules will be smaller, we’ll be able to stack them right next to the firewall up front. And that’ll help balance it off because the beaver aircraft has always been traditionally a relatively tail heavy aircraft. So it’s always been a bit of a challenge to move everything up front. So we’re trying to stack it even the ones that go in the back will probably be stacked such that you know more in the first row and then sort of fewer as you get further back trying to keep the weight as far forward as possible.”

The Path to Certification

Harbour Air’s journey toward electric flight is not without hurdles. Retrofitting existing aircraft, like the Beaver, simplifies certification compared to building entirely new planes. However, they still need to contend with regulatory challenges. Traditional regulations do not encompass electric aviation, so they’ve had to work with aviation authorities like Transport Canada and the FAA to create special regulations tailored to electric power plants.

“So, if you look at the regulations for FAA certification of aircraft power plans, part 33, it talks about piston engines, and it talks about turbine engines. There is nothing in there about any other kind of technology. So we actually work with the FAA to define, we work with the FAA to define what are called special conditions. So, they basically said, you know, there’s no regulations for the technology that you’re trying to do. So we’re going to create special regulations to accommodate your power plants. And then if you show compliance to these special regulations that we wrote, then we will give you a type certificate for your engine” explains Marmol.

However to achieve this certification, MagniX and Harbour Air must lock in on a design and stick with it through the certification process. “We have to lock in at some point for the prototype build purposes and for certification purposes. So I have to pick an architecture and we go with it. And by the time we get to certification, it’s going to be two years outdated and there’ll be a lot better technology out on the market at that time. But we can’t take advantage of it until we act to get something certified, creating the path to certification.” says Holtz

This pioneering effort, though fraught with challenges, is essential in paving the way for the broader adoption of electric aviation. Electric engines offer immense potential for reducing both maintenance costs and fuel expenses. Erica Holtz explains that their 100-hour inspections will likely become 300-hour inspections, and engine component overhaul intervals will extend, further reducing operating costs.

Yet, one substantial challenge remains: charging infrastructure. While Harbour Air’s aircraft can recharge in about three to four hours at their base with a 75-kilowatt charger, away from base, they’ve encountered significant delays due to a lack of suitable charging options. The solution may lie in microgrids and reusing retired battery modules for on-ground energy storage.

A Broader Impact on Aviation

While Harbour Air’s immediate focus is on retrofitting their de Havilland Beavers, their pioneering work holds promise for the broader aviation industry. Electric technology, particularly in a hybrid form, can enhance the efficiency of larger aircraft, reducing fuel burn during takeoff and climb, which are critical phases of flight.

Marmol explains “What looks most promising right now is hybrid light hybridisation. So having an electric motor that’s attached to the turbine is through the gearbox. And the engine is designed for operating at 75% power for cruise and climb. And then that extra 25 or 30%, is provided by the electric motor for takeoff and go around and things of that nature.”

Ultimately, achieving sustainable aviation requires a collaborative effort involving governments, airlines, airports, and passengers. Public interest has already resulted in substantial government funding for electric aviation initiatives. Harbour Air encourages people to voice their support for these technologies, acknowledging that the path to sustainability may come at a higher initial cost but offers significant long-term benefits.

The road ahead for electric aviation is challenging, with constant technological advancements and the need to balance regulatory requirements. Nevertheless, pioneers like Harbour Air and MagniX are lighting the way, proving that electric flight is not only possible but the future of environmentally conscious aviation. As the industry takes flight in this new direction, the sky’s the limit for electric dreams.

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