Hybrid electric automobiles are now part of the landscape and hybrid aircraft are on the way, and sooner than we think.
Alaska is poised to take center stage for some of the rollout of this new technology because the size and types of aircraft commonly used on bush air routes, like Twin Otters, will be among the first commercial aircraft to be partly powered by electricity.
The types of flying done in in rural Alaska, with short village-to-village hops delivering freight and passengers also fit well with the economics that hybrid aircraft will offer, with lower fuel use and operating costs.
Hybrid systems have potential for reducing fuel use by 20 to 50 percent, depending on the route and type of aircraft, says Cory Combs, the co-founder of Ampaire.
Ampaire, based in Los Angeles, is a leading company in the new field of all-electric and hybrid small to medium-sized aircraft and is working on a NASA contract to build a hybrid electric Twin Otter, a type and size of aircraft widely used in Alaska.
Ampaire sees Alaska as a prime market for new hybrids, which it believes can offer big fuel savings on flights that are relatively short range. Ampaire has tested its smaller hybrid aircraft in California and Hawaii and will do so soon in Scotland and England, Combs said.
These places are potential markets for hybrid commuter-type aircraft because passenger and freight often move by air in short hops, such as island-to-island in Hawaii. Other arctic locations, such as Norway, already have plans in place do adopt electric and hybrid aircraft for similar uses as those found in Alaska.
Combs is a former Northrop Grumman engineer who worked in the company’s advanced aircraft unit. Ampaire’s other cofounder, Kevin Noertker, worked in Northrop Grumman’s electronic systems unit. The two started Ampaire in 2016.
Ampaire plans to develop and test components of its hybrid electric propulsion system in cold weather conditions in Alaska. Merrill Field, Anchorage’s city-owned general aviation airport, may play a role in development testing of the technology.
Launch Alaska, an Anchorage-based nonprofit that works with small tech startups in development, is looking to acquire facilities at Merrill Field for conversion to a tech center in cooperation with Ampaire.
Launch Alaska has a U.S. Economic Development Administration grant that is helping fund an aerospace development program with startup companies like Ampaire and recently landed a $1 million U.S. Department of Energy grant that will help further its transportation technology initiatives.
Combs said companies like Ampaire are potentially interested in the Merrill Field because it could offer to hangar space and runway access as well as an indoor working environment.
In another development, Rural Alaska air carrier Ravn Alaska is interested in hybrid electric aircraft and has signed a conditional order for 50 aircraft from Airflow, another new California company in the hybrid aviation market.
Ravn is interested in Airflow’s concept of a nine-passenger aircraft with a 500-mile range that will be able to take off on short runways. Unlike the aircraft already being modified and tested by Ampaire that are based on existing airframes, the design aircraft planned by Airflow is still under development and must be built, tested, and licensed.
Ravn’s “order” just puts the company in the queue for when the plane is available – no firm commitment is made. Ravn is interested because going hybrid electric could reduce its operating costs for small cargo aircraft.
Combs said hybrid aircraft function like hydrid cars in that they carry dual propulsion systems, both electric and conventional combustion, to lower emissions and also achieve savings through lower fuel consumption.
In one implementation of hybrid propulsion, electric power would be used while taxiing on runways, where there is now a high and inefficient use of fuel. During takeoff the aircraft would be at maximum power with both combustion and electric power used.
At cruising altitude, as with automobiles, pilots would use a mix of electric and combustion power at a lower total power setting. “This mix would depend on the flight distance, with shorter flights able to rely more heavily on electric power. In descent and landing, electric motors can even regenerate some power as the aircraft loses altitude and slows down,” Combs said.
“Dual power is also important if there are flight diversions , because having extra fuel available offers the ability to extend flight duration without increasing battery size. Such emergency reserves are required for safety by the FAA,” he said.
Combs said a lot of research and development is being done for all-electric aircraft but so far the weight of batteries creates a limitation, so the only practical all-electric airplanes being tested right now are small aircraft, typically trainers, that would carry small loads and operate at short range.
But the evolutionary path is clear.
Just as improved and lighter-weight batteries, and wider availability of charging stations, are making all-electric cars more popular, aircraft will eventually follow suit, Combs said. But hybrids are where the action is for now.
Apart from reducing operating costs, what’s driving the development, just as with electric automobiles, is the prospect of reducing greenhouse gas emissions. According to some estimates aviation may be contributing as much as 5 percent of worldwide greenhouse gas emissions, which are a key factor in climate change and global warming.
Emissions at higher altitudes, where many aircraft fly, are reported to be more worrisome because of a “compounding” effect on atmospheric warming. Reducing the emission of other pollutants, such as lead, as well as noise is also a significant factor.
It will take years for larger passenger aircraft to be fitted with hybrid electric technology, which will reduce much of the pollution, but the advances being made now for smaller and soon medium-sized aircraft mean that it will eventually happen for larger airplanes.