Power unit developer Ampaire is ground testing the propulsion system on its first hybrid electric Cessna Grand Caravan test aircraft, the Eco Caravan.
This aircraft represents a milestone for hybrid electric aviation, building on the technology and heritage of Ampaire’s Electric EEL aircraft.
The upgraded Eco Caravan offers significant fuel savings over the original aircraft of up to 70% on short-hop routes and over 50% on long-haul flights, while still carrying 9 passengers or cargo, said Ampaire. The aircraft can achieve an emissions reduction of up to 90% if using sustainable aviation fuel. The Eco Caravan is capable of operating from airports without electric charging infrastructure.
Ampaire says it will proceed with development of the Eco Caravan and the application for a supplemental type certificate (STC) for its hybrid propulsion system.
“Powering up a new propulsion system, one that is fully integrated into a flyable aircraft, is a tremendously exciting milestone for Ampaire,” said CEO and co-founder Kevin Noertker.
“We expect the Eco Caravan to be the first in a series of hybrid electric upgrades for a number of aircraft models that will transform the industry by lowering emissions and costs.”
Noertker described the first ground power runs at Los Angeles’s Hawthorne Airport as an initial validation of the system’s operation. First flight of the Eco Caravan is expected in the second half of 2022.
Working with the FAA towards certification
Jon Adams, Director of Certification at Ampaire, said about certifying the Eco Caravan, “With 200 or so electric aircraft programs (plus hydrogen-powered aircraft and new conventional aircraft) all striving to reach the market, you might wonder how our beleaguered civil servants are able to provide proper oversight and help industry innovate.
“The answer: It’s a struggle.
“Congress, in establishing the FAA in 1958, gave it a dual mandate to promote civil aviation and regulate safety — an often tricky balancing act. But one the FAA takes quite seriously. It recently formed the Center for Emerging Concepts and Innovation (CECI) to foster new technologies and better manage the flow of new certification programs.
“The head of CECI, James Wilborn reported at the SAE AeroTech 2022 conference that it has eight managers in the program integration role and already 70 innovation projects in the pipeline. The Eco Caravan is the first hybrid-electric aircraft to enter the FAA certification process. “Because the agency has never certified such a propulsion system, it does not fall neatly into existing certification rules. When this happens, and it happens quite a bit, the FAA develops new guidance and materials such as “Special Conditions,” “Issue Papers,” and “ELOS” (Equivalent Level of Safety). These are new rules that an aircraft and its propulsion system must meet.
“Because Ampaire is the first to enter the FAA approval process with a hybrid-electric aircraft, it will play a big role in helping to establish the standards for this propulsion category. CECI, in working with Ampaire in this new area, is committed to conducting a collaborative effort to develop new certification standards.
“Ampaire will shorten time to market for initial products by pursuing a supplemental type certificate (STC) for a new propulsion system to be installed on an already certified aircraft. The STC process is typically significantly shorter and less risky than certifying an all new aircraft. Ampaire seeks to bring the Eco Caravan to market in 2024.
“By contrast, full aircraft certification can be a long and winding road. It took eight years for Boeing to certify the 787, which broke new ground as a mostly composite airplane with a higher level of electrification at the systems level.
“It took Beechcraft (now part of Textron) more than 10 years to certify the Hawker 4000 business jet. These examples from established manufacturers suggest that companies expecting to certify all-new electric aircraft by 2024 are facing major hurdles.
“All the more reason for Ampaire to continue on its practical path and foster a close collaboration with the FAA. We’re off to a good start.”
