Electric airplane towing concept could mean longer zero-emission flights

Magpie Aviation announced a novel new approach to electric airplanes on Monday. Today’s battery technology (including CATL’s new, more efficient one) severely limits the practicality of zero-emission aircraft, leaving clean-energy innovators with two incomplete options: flying a plane full of batteries or one full of people — but not both. So the California-based startup wants to tie them together, extending the rear plane’s range by hundreds of miles.

Towing planes isn’t a new concept, with military use going back to World War II when aerial tows would pull smaller aircraft carrying troops and supplies. But applying it to the world of green transportation is new. Magpie Aviation’s concept uses one or more electric aircraft to act as a tractor plane towing a passenger (or cargo) aircraft using a long cable. The towed plane would have enough battery power for takeoff, landing and flying to alternate airports but not enough to fly the full distance on its own, as reported by AeroTime.

The lead plane would take on the bulk of the traction, and when its battery is depleted, it could hand off towing duties to another electric towing aircraft to extend the rear plane’s range. Magpie CEO Damon Vander Lind summarized to Aviation Week, “You get towed until you’ve depleted down to your reserve in the lead aircraft, and then you swap in another tow aircraft.” Although it’s still a regional solution impractical for cross-country or international flights, Vander Lind says it could allow for a trip from San Francisco to Seattle — far beyond the sub-regional distances battery-powered passenger flights can travel on their own.

Magpie says it’s conducted successful small-scale tests using a synthetic fiber rope around 330 ft. long; the company envisions a later commercial version to use nearly mile-long cables. The startup plans to scale up its testing gradually and believes it could be implemented commercially by 2030. It expects advances in battery tech to allow it to tow single-aisle airliners eventually. Magpie suggests that the concept, mainly targeting electric planes, could also work with hybrid, hydrogen and standard aircraft in low-power modes. Additionally, the company says it’s working with the Federal Aviation Administration (FAA) with an eye toward certification.

“It sounds kind of crazy, but we kept coming back to it because we couldn’t find any reason why we couldn’t do it,” said Vander Lind. “While our modeling shows that there is an advantage to doing a custom tow aircraft like this, we get a big advantage because the more expensive and critical passenger- and cargo-carrying ‘main aircraft’ has similar requirements to today’s aircraft and so adapts well to existing in-operation and already-in-development platforms. Remember that if we want to hit a zero-carbon 2050 goal, an airliner has a 30-year life, so we’re already at the point where airlines have to think hard about the operating life of the assets that they are buying today.”