As air journeys go, it was just a short hop into the early morning sky before the de Havilland seaplane splashed back down on the Fraser River in Richmond, British Columbia. Four minutes earlier it had taken off from the same patch of water. But despite its brief duration, the flight may have marked the start of an aviation revolution.

Those keen of hearing at the riverside on that cold December morning might have been able to pick up something different amid the rumble of the propellers and whoosh of water as the six-passenger de Havilland DHC-2 Beaver took off and landed. What was missing was the throaty growl of the aircraft’s nine-cylinder radial engine.

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In its place was an all-electric propulsion engine built by the technology firm magniX that had been installed in the aircraft over the course of several months. The four-minute test flight (the plane was restricted to flying in clear skies, so with fog and rain closing in the team opted for a short trip) was the first time an all-electric commercial passenger aircraft had taken to the skies.