Maxwell’s M1 Hybrid Amphibious Cargo Plane Uses Electric Power for Takeoff and Diesel for a 1,150-Mile Flight

Maxwell M1 Hybrid amphibious cargo seaplane, Digi Mart USA News (Florida, United States): Florida-based Maxwell Aircraft is developing the M1 Hybrid, an amphibious cargo aircraft that combines electric motors with small diesel engines. According to the company, the design is patent-pending and is intended to address the fact that conventional aircraft carry engines sized for takeoff even though they use only a fraction of that power in cruise.

Each of the aircraft’s two propellers is driven by a two-stroke diesel engine running on Jet A fuel, mechanically linked through a liquid-cooled electric motor. The system is designed to be driven by electric power, Jet A power, or both.

The pair can theoretically deliver up to 1,500 hp (1,119 kW), but CEO David Dillon told New Atlas that this output is restricted to takeoff and initial climb, or about six minutes of operation, which keeps battery weight low while providing the power needed to lift a full ton of payload off the water.

In cruise, the two engines provide about 300 hp (224 kW) combined. The first version, the M1-HC freighter, has a 5-ft (1.5-m) cargo door for palletized loads.

Maxwell is aiming for 2,000 lb (907 kg) of payload over 1,000 nautical miles (1,852 km) in a single flight. The company pitches the amphibian for remote communities, island operations, disaster response and defense work, since it can use waterways as well as rough strips.

The airframe is made from carbon fiber and Kevlar and is based on the Gweduck, a composite amphibian that first flew in 2009. Maxwell describes it as a fifth-generation evolution of the Grumman seaplane design and says composites resist the salt-water corrosion that affects metal hulls. Dillon said the engines have already logged substantial test-stand time, though he has not said whether the full hybrid drive has been run.

Maxwell expects to show the M1 at the Lakeland Air Show in Florida in April 2027, although it will be displayed with standard Lycoming engines. The hybrid version is expected to follow in the fourth quarter of 2027. The company says the first airframes have come out of the Carbon Seaplanes factory.

The source does not independently verify the performance claims.