The Future of Advanced Air Mobility

How Hybrid-Electric Aircraft Could Transform Caribbean Island-hopping Flights

With the prototype for Ampaire’s Eco Caravan conversion of the ubiquitous Cessna Grand Caravan EX turboprop scheduled to make its first flight by the end of the year, the California-based hybrid-electric propulsion system developer has been touting the aircraft’s benefits for Caribbean island-hopping operations. At the Caribavia conference in St. Maarten this week, Brice Nzeukou, the company’s director of business and product development, argued that the aircraft—outfitted with an electric motor driving its propeller along with a conventional jet fuel-powered engine—is uniquely suited for use in the Caribbean.

At an expected average of 20 gallons of fuel burn per hour, the Eco Caravan’s consumption is less than half that of a conventional Caravan due to the assistance on takeoff and climb out from the hybrid-electric power plant. In addition to the environmental benefit of reducing emissions, that translates to a higher payload for the hybrid version over the conventional Caravan on short flights, or a near doubling of range.

With a 25 percent reduction in direct operating costs, the conversion could allow operators to reopen old routes that were deemed unprofitable, or establish new routes based on the operational economies the hybrid aircraft would afford. On regular routes, those savings could allow the operator to reduce fares and increase demand and revenue.

As an example, Nzeukou used St. Barth’s commuter airline, which currently operates the Grand Caravan EX. For the 20-mile flight between Grand Case-Espérance Airport on the French side of St. Maarten and St. Barth, typically flown at an altitude of 1,000 feet, the Eco Caravan would burn five gallons of fuel compared with the Grand Caravan’s 13.2 gallons, leading to an overall cost per trip of $100 for the hybrid and $173 for the standard aircraft.

The company estimates that the hybrid Caravan would have a range of 470 nm with 10 occupants, allowing it to reach as far as the Dominican Republic or Grenada from St. Maarten. Nzeukou noted that due to the relatively short distances between islands, operations in the region are generally characterized by high cycle-to-flight-hour ratios, increasing the maintenance costs on turbine aircraft by hitting life limits on the rotating section more rapidly and leading to overhauls every two years, even if the normally scheduled time between overhaul intervals is up to 5,000 flight hours.

“Our combustion system does not tap any life-limited parts,” said Nzeukou. As well, given most inter-island activity takes place at low altitude, that would allow the aircraft to make multiple round trips before having to charge the system’s battery, which would give it a higher cycle time between recharging and improve the powerpack’s longevity. The Eco Caravan does not require any specialized infrastructure as its battery can be recharged in flight, or on the ground, using the hybrid powerplant.

Ground testing began earlier this year, and Ampaire expects to receive a supplemental type certificate (STC) for the aircraft, with entry into service by mid-2024. It plans to eventually offer the hybrid powerplant as an assembly-line option direct from the Cessna factory, and also has ambitions to convert other aircraft types.

Ampaire has previously conducted test flights with its Electric EEL technology demonstrator aircraft in Hawaii and the UK.