The 30 kW electric machine developed for H3PS serves both as a motor and as a generator. It works as the starter-motor to start the combustion engine. During take-off and climb it is a thrust booster-motor adding extra torque to the propeller shaft. In the air, when the aircraft is cruising, it operates as a generator and converts the shaft movement into electric energy to re-charge the batteries.
As the electric motor contributes to the aircraft propulsion, the combustion engine can be reduced in size. For the Tecnam P2010, the 180 hp standard engine has been replaced with a smaller engine with only 141 hp – and this leads to a significant reduction in fuel consumption.
The reduction in engine size has further benefits. It means the aircraft can go further on its existing fuel tank, and because the engine is always running at its optimal operating level it is more efficient and experiences less wear and tear, resulting in reduced maintenance costs and ultimately a lower cost of ownership. It is also lighter.
As downsizing the engine frees up payload, the battery can be accommodated without adding significant extra weight to the overall system, therefore maintaining the aircraft’s positive efficiency balance.
Balázs is convinced that small electric and hybrid-electric planes will have an enormous impact on the way the public and pilots experience electric flight and will help accelerate demand for such solutions in larger aircraft. “They are ideal for our pioneering work – for testing electric engines, and for training pilots and operators on new drive systems. With research projects such as the H3PS, in close collaboration with our partners, we can demonstrate highly innovative technologies for a small plane, learn key lessons and stimulate innovation that will reduce the environmental impact of air travel in the long run, even in larger aircraft classes.”