Zunum Aero, an Electric Airplane Startup Backed by Boeing and JetBlue Ventures, Unstealths

by Katie Fehrenbacher

Elon Musk often says he thinks all transportation will go electric, with the exception of rocket ships. Will it one day be commonplace to take electric airline flights?

A startup called Zunum Aero hopes so. On Wednesday the company founded in 2013 and based in Kirkland, Washington is talking about its plans for the first time. The company has a goal to build an electric hybrid aircraft in the early 2020s, and its first prototype within the next two years.

Co-founder and CEO Ashish Kumar says electric air transportation is a potential “economic disruption.” Why? Because the costs of the batteries that could propel planes is quickly dropping, while regional airliners are spending large sums on using jet fuel to fly short-range trips.

Zunum Aero wants to target those shorter hauls, like Silicon Valley to Los Angeles, or Boston to Washington, D.C., with its battery-powered planes. Kumar thinks the hybrid electric planes will eventually be able to make those types of trips with 40 percent to 80 percent lower operating costs and in half the time.

It’s an aggressive goal, especially for a young company still in the design phase of building an aircraft. The company has fewer than 10 full-time staff members currently, but plans to triple that amount in the coming years.

Kumar has a background working at tech companies, while his co-founders, Matt Knapp and Kiruba Haran, have had careers in the aerospace and electric drivetrain sectors.

Kumar wouldn’t disclose how much funding the company has raised, but said that Boeing and JetBlue Technology Ventures JetBlue’s investing arm have backed the company. It will likely take tens, if not hundreds, of millions of dollars to build an electric airline fleet.

Given that the company’s first prototype won’t be out for another two years, the designs aren’t entirely fleshed out. Kumar said Zunum Aero's batteries would likely be advanced lithium-ion or potentially solid-state batteries.

“We’re tracking 30 different manufacturers making batteries. The aircraft will use the best that’s available,” said Kumar.

Kumar expects the batteries will have an energy density of at least 300 watt-hours per kilogram. By comparison, Tesla’s Model S batteries are estimated to be closer to 250 watt-hours per kilogram.

The aircraft will be a battery first series hybrid, or an electric-powered aircraft with a range extender sort of like General Motors’ Chevy Volt. All of the propulsion will come from the electric motor, said Kumar, and if there’s enough battery power to run the entire flight, the jet fuel won’t need to kick in. The company will also offer all-electric options.

Battery-powered airplanes aren’t popular. The big airline companies have more commonly experimented with biofuels to power flights, using the fuel in traditional airplane engines.

That is partly due to safety concerns around lithium-ion batteries, some of which can be volatile if not properly operated, managed and manufactured. Boeing had its Dreamliner temporarily grounded after a battery fire; it used two large lithium-ion batteries for an auxiliary power unit and to power flight deck computers.

Solid-state batteries, which use solid polymers instead of liquid for the electrolyte, have a better reputation than traditional lithium-ion batteries when it comes to safety. However, solid-state batteries are still in an early stage of production at both startups and big battery conglomerates.

Despite the lack of electric planes out there, some entrepreneurs predict that the electrification of transportation will continue from the ground into the skies. Electric airliner makers will take lessons from the growing electric car industry like battery management, charging and software and apply them to an emerging industry.

Inventor and entrepreneur Martine Rothblatt has worked with a team building a battery-powered helicopter that could one day transport transplantable organs. The electric helicopter flew last year at an airfield in Southern California for the first time.

Elon Musk has also long discussed his idea for an electric plane that could take off and land vertically. To fly across the country, Musk has said batteries would need to be closer to 400 watt-hours per kilogram. That’s a significantly higher energy density than the ones that Tesla currently uses.