Small Electric Planes Could Help Decarbonize Air Transportation

Surf Air Mobility expects to obtain regulatory approval to fly a nine-seat hybrid-electric plane by late 2024.

A Surf Air Mobility experimental test plane.
A Surf Air Mobility experimental test plane.

Surf Air

Several startups are trying to develop small electric and hybrid planes that may pave the way for zero-carbon air transportation.

Although aviation only accounts for about 2% of all the carbon we put in the atmosphere, before the pandemic hit, emissions from the sector were expected to grow rapidly amid a potential boom in air transportation in the coming years. 

Large electric or hydrogen jets won’t be available for at least a decade but in a bid to shrink their carbon footprint, major airlines plan to start using sustainable fuels that will be produced mostly from recycled food and agricultural waste. According to the White House, these efforts could allow airlines to slash emissions by 25%.

Given the weight and range limitations of existing battery technology, for the time being, aviation companies only envision using small electric planes for short-distance traveling. 

Canada’s Harbour Air is seeking authorization to use a fully-electric six-seater seaplane called eBeaver to transport passengers and Slovenia’s Pipistrel has developed an all-electric two-seat pilot training aircraft. Other companies, including France’s VoltAero and Canada’s Pratt & Whitney and De Havilland are developing hybrid-electric planes. 

In comes Surf Air Mobility, a California startup that aims to retrofit nine-seater Cessna planes with a hybrid propulsion system that would cut emissions by 25% when compared to planes powered by traditional turboprop motors. Surf Air Mobility has signed an agreement to acquire at least 100 Cessna Grand Caravan, in which it plans to install hybrid-electric powertrains. The company wants to operate some of the hybrid planes through an airline and sell the rest to clients.

Treehugger recently interviewed Surf Air Mobility President Fred Reid to learn more about the company’s ongoing test flights and its future plans:

Treehugger: Why developing a hybrid plane instead of a fully electric one?

Fred Reid: We're looking at hybrid because it's achievable very soon. We estimate late 2024. Also, currently, you hardly have any chargers at airports, but hybrid planes can work anywhere and they can be reconverted or upgraded yet again to all-electric. 

One of the big differences between us and other companies is that we've been flying a hybrid Cessna Skymaster for three years now, and we've had two aircraft given experimental certificates. We flew in Hawaii for about 45 days last year and we flew around Cornwall, in Southwest England, and around the Orkney Islands in Scotland. We plan to start flying a Cessna Caravan on an experimental certificate in about 12 to 15 months.

Can you tell us more about the range of the planes?

The range will be about 400 miles. I think the sweet spot, where you can carry a full payload, will be 150 to 300 miles. That will connect literally thousands of city pairs or airport pairs that are not served by any aviation today because they're very small. And when you're filling a nine-seater or a 19-seater, you can go to small markets that the airlines abandoned a long time ago when they focused on bigger jets. There're 5,000 public airports in the U.S. but less than 10% are used for scheduled passenger service. So you have about 4,500 airports with very little service and 90% of the American population lives less than 30 minutes from a small airport. 

How will the emissions of a short-haul flight on a hybrid-electric plane compare to traveling by car?

It depends. If you're driving a Tesla, it's comparable, but if you're driving a traditional car, and bear in mind that Americans like big trucks and big SUVs, it will definitely be better than that. And there will also be time savings. 

Is there a market for small hybrid planes outside of the U.S.?

This is a global play because there are more than 25,000 small planes worldwide, in Africa, Asia, South Asia, Russia… everywhere in the world. Not only will we develop new planes but we will also offer small plane owners a service to upgrade their aircraft to a hybrid configuration, which will give them 30% in savings and make their aircraft more reliable. Local air transportation is very expensive today but hybrid and electric reduce the cost of operating by a lot, and they suddenly make uneconomical planes economical.

When do you expect to obtain a permit from the Federal Aviation Administration (FAA) to fly the plane?

The FAA approves new aircraft, which can take many years, and modifications to existing aircraft, which are much easier. We're going to convert planes the FAA already knows. We're not touching the wings or the landing gear, or the tails or any of the things that make the aircraft fly. We're not even removing the gas engine. We are just adding an electric motor. So, if the motor fails, which is almost unheard of because electric motors tend to never fail, you still have the gas option, and the FAA knows that. It's going to take a couple of years because this is a rigorous process, but it's something we expect to have by 2024. 

Do you foresee using hybrid Cessna planes to transport cargo?

Absolutely. We might be announcing a fleet order, from a major regional airline, soon for cargo. UPS, DHL, FedEx, and Amazon fly small planes because that's the best way to get to small markets. So yes, cargo is definitely in the mix because transport companies are very committed to sustainability. 

Do you plan to develop fully electric planes?

We’re 100% committed to all-electric but battery technology has to improve because if you do all-electric right now, the battery is so heavy that you can't fly very far and you can't carry a full load. In the coming years, certainly in this decade, we will have hybrid and we'll have pure electric, but hybrid will always be sold no matter what happens with electric. The Toyota Prius came out 25 years ago, and hybrid cars continue to outsell electric. We will sell hybrids forever. We'll be selling electric planes at some point as well but hybrids are not a temporary solution, they are a permanent solution.

View Article Sources
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  3. "Biden Administration Advances the Future of Sustainable Fuels in American Aviation." White House, 2021.