eCaravan: a tidbit

eCaravan, an electrified Cessna 208B Grand Caravan, awaiting its first test flight (Photo: MagniX)

On 2020-05-28 aviation history was made, with the first 30 m test flight of an eCaravan, an electrified Cessna 208B Grand Caravan at Grant County International Airport in Moses Lake, Washington. The eCaravan was modified in Goldcoast, Queensland, Australia by Magnix, so that it is powered by a 560 kW magni500 all-electric propulsion system with a 1 tonne, 750V lithium-ion battery. The flight consumed $6 worth of electricity, needing 30-40 min of charging.

The electric aircraft propulsion company MagniX worked with engineering and flight test specialist AeroTEC on this project. In its current state, the Magni500-powered plane can fly 160 km with 4 or 5 passengers while keeping reserve power. The companies are aiming for a certification by the end of 2021.

In a slightly more distant future, the companies hope to offer machines capable of operating 160 km flights with reserve capacity, and a full load of nine passengers. The longer term goal is to enable 800 km flights, which account for about 45% of all flights flown in the world. Some decades ago, smaller commuter airlines operated such routes. The general aircraft operating these routes disappeared because they were economically unviable. They were replaced by larger, more complex regional jets. Electric aircraft could provide the economic characteristics that make such routes feasible again. However, it is the relatively low energy density of batteries that has constrained the range and payload of electric aircraft. Magnix is studying other technologies, including lithium-sulfur batteries and hydrogen fuel cells.

The advantage of electric propulsion systems is their environmentally friendly operation, fewer moving parts and simplicity, compared to ICE engined aircraft. Some estimate that electric propulsion will reduce operating costs by up to 80%.

In a previous weblog post, Alice, an all-electric, nine-passenger aircraft being developed by Eviation Aircraft, was discussed. That project was disrupted in 2020-01 when an electric system fire damaged an Alice prototype in Arizona. Magnix had also been named one of two companies to supply propulsion systems for it.

The eCaravan in flight at Moses Lake, Washington, USA, 2020-05-28. Photo: Magnix

This weblog post was updated 2020-06-05.

Eviation Alice

The Eviation Alice. image: Eviation.

Alice is an electric aircraft being developed since 2017 by Eviation Aircraft of Israel. A first flight is expected sometime in 2020, followed by a certification program lasting two to three years. Composite materials form 95% of the plane. It will be controlled by fly-by-wire (a system that replaces manual flight controls with electronic ones) and powered by three pusher propellers (facing backwards) , two on the wingtips and one at the rear of the fuselage.

Eviation was founded in 2015 by Omer Bar-Yohay, Omri Regev and Aviv Tzidon. Eviation teamed up with Embry-Riddle Aeronautical University (ERAU) to launch a research and development program to start in the spring of 2019 at ERAU’s Prescott, Arizona campus. The program would focus on performance analysis, validation and testing, along with preliminary design and sub-scale testing of future electric propulsion and airframe design concepts.

Eviation has secured $200 million of investment to cover certification and production while the first prototype was assembled in Vannes, northwest France. This site was chosen, because it is the location of composite materials specialist, Multiplast. Other suppliers include: Honeywell is providing flight control systems, including automatic landing. Magnaghi Aeronautica will supply the landing gear. Kokam Company will supply pouch lithium polymer batteries to power the full-scale prototype. While Siemens 260 kW motors had been selected as a primary power source, MagniX Magni250s 280 kW motors were selected as a second power option. This ranking may change as MagniX owner Clermont Group from Singapore took a 70% stake in Eviation Aircraft in August 2019.

Charge vehicles, similar to aviation fuel trucks, would be used to charge the plane. Each hour of flight time was expected to require a charging time of 30 minutes.

The planes have a unit cost of $ 4 million. Currently, over 150 Alice aircraft had been ordered by two American companies. An investment of $500 million is needed to begin serial production.

Alice flight deck. Image: Eviation.
Alice interior. Image: Eviation.
External Dimensions
Length13.2 m 
Wingspan16.12 m
Height4.2 m
Performance
Cruise speed 445 km/ hour = 240 KTAS
Takeoff field length914 m
Cruise altitudeca. 3 000 m
Service ceilingca. 3 800 m
Range540 NM = 1 000 km (+45min IFR reserve)
Characteristics
Occupants9 Passengers (+ 2 crew)
Useful load1 134 kg
MTOW (Max Take-Off Weight)6 350 kg
Power900 / 260 kW (peak/cruise)
Battery & Operations
Battery920 kWh
Battery chemistryLithium Ion (NMC)
Battery weight3,600 kg (~60% MTOW)
Direct operating costs$200/ hour

ePlane: A tidbit

Harbour Air DHC-2 Beaver floatplane in Richmond, British Columbia, powered by an electric magniX magni500 propulsion system. Photo: Harbour Air.

On 2019-12-10 Harbour Air successfully flew the world’s first all-electric commercial aircraft, the ePlane, a six-passenger DHC-2 de Havilland Canada Beaver on floats, with call sign C-FJOS and production number 1030 of the 1 692 DHC Beavers ever built. Originally delivered with a piston ICE engine on 1957-03-01, it spent most of its operational life based in Prince Rupert, British Columbia.

This aircraft, with yellow and blue livery, is now powered by a 560 kW magni500 propulsion system. Its first electric propulsion flight started and ended on the Fraser River at Harbour Air floatplane terminal in Richmond, British Columbia at YVR South, part of Vancouver International Airport.

Richmond is the home base of Harbour Air, North America’s largest floatplane airline. It specializes in routes between Vancouver, Nanaimo, Victoria, Sechelt, Comox, Whistler and the Gulf Islands. There are also flights between downtown Vancouver and downtown Seattle. They also have a European subsidiary in Malta.

Harbour Air has a history of green operations, that is deeper than a typical greenwash. In 2007, it became the first airline in North America to achieve complete carbon neutrality in both flight services and corporate operations. It has announced its intention to build the world’s first completely electric commercial floatplane fleet, but because of certification requirements, including testing, it will have to wait until about the beginning of 2022 before this can start. The company is regarded as one of the best managed in Canada, and has won awards for this.

The Harbour Air fleet consists primarily of de Havilland Canada floatplanes: 14 DHC-2 Beavers (5 – 6 passengers), 21 DHC-3-T(urbo) Otters (10 – 14 passengers) and 3 DHC-6 Twin Otters (18 passengers).

In March 2019, Harbour Air announced a partnership with magniX to electrify the entire Harbour Air fleet over the long term. Harbour Air has noted that its initial electric-powered commercial flights will be on routes of under 30 minutes’ duration. The DHC-2 Beaver serves as the test prototype for the magniX motor, energy storage, and control systems.

MagniX is an Australian electric motor manufacturer for electric aircraft, wholly owned by Singapore investor Clermont Group. Its engineering headquarters is located on the Gold Coast, Queensland, Australia. Its global headquarters and US development centre is located in Redmond, Washington, near Seattle.

One of the main advantages of an electric motor in an aircraft is full torque at low RPM. In addition, the mechanics are simpler, reducing the number of parts as well as weight. For example, a propeller can be attached directly to the motor without a reduction gear.

The magni500 was unveiled at the Paris Air Show in June, 2019. It provides 560 kW, and 2800 Nm of torque. It weighs 135 kg. The smaller magni250 motor provides 280 kW, and 1400 Nm of torque. It weighs 72 kg. Both types of motors rotate at between 1900 and 3000 RPM, and offer 93% power conversion efficiency. Both motors can be regarded as high-power-density electric propulsion systems that provides a clean and efficient way to power airplanes. The company also makes a magniDrive 170 kW power electronics system used to run both the magni250 and magni500.

Sources: Beaver Tails ; Harbour Air ; Magnix ; Wikipedia – Harbour Air Seaplanes & Magnix .