The European air transportation market is expanding by 4 % per year. This creates a steady demand for new pilots. According to the EU-funded WATTsUP project, the future of pilot training will be electric aircraft. Being zero-emission, they offer environmental advantages. They are also quiet to operate, which makes them available for training at minor airfields that would otherwise be closed on weekends for noise reasons. Secondly, these aircraft are cheaper to operate; they require little maintenance, and the per hour cost of electricity is less than fuel which reduces pilot training costs as well. The electricity bill for an hour’s flight, for example, is only around EUR 2! The WATTsUP consortium developed a prototype training vehicle, of the light sport aircraft class, into a mature product. The project is the first to achieve a production line dedicated to such craft. New power system Like most modern aircraft, the two-seater WATTsUP craft is built from light composite materials. Most innovative are the electric drivetrain technologies. Thrust comes from a lightweight 60-kW electric motor attached to an energy-recouping forward-mounted propeller. The vehicle’s motor and power controller were specifically developed for aviation propulsion, and include a cooling system that optimally circulates liquid around the motor and air around batteries. Either of the two 10.5-kWh batteries alone can power the aircraft if the other fails. The battery management system optimises charging and discharge during all flight phases. The project also developed new throttle-by-wire protocols and all related electronics, the propellers and tools for their design, plus a completely new fuselage to accommodate the unconventional componentry. Researchers conducted all testing and validation necessary to globally certify the aircraft. Easy to use Since conventional cockpits include neither instruments nor controls for electric aircraft, the team had to design an entirely new cockpit interface. “The combination of graphic flight instruments and charger displays, and a new power lever, make the aircraft as simple to use as a cellular phone,” says Dr Igor Perkon, R&D Program Manager for Pipistrel Vertical Solutions, the key project partner. The aircraft can exceed cruising speeds of 200 km/h, while current battery technologies allow a 1-hour flying time plus small reserve. This range is sufficient for training purposes, but not cross-country flight. In the same way charging stations for ground vehicles are spreading across European highways, Dr Perkon anticipates that similar charging networks will spread across European airfields. “For example,” he adds, “Switzerland, has been positioning strategically placed charging stations on its airfields, to allow cross-country flying with zero emissions.” The fast-charging system permits recharging in 40 minutes. WATTsUP also created an innovative set of online tools for flight schools’ needs. The syllabus is intentionally interactive and easy to understand. A fleet management portal simplifies students’ booking of training flights. The team demonstrated the product at European air shows and other events. The exposure resulted in dozens of orders being placed before production started. Since the project concluded at the end of 2017, almost 30 aircraft have been delivered to customers. The WATTsUP trainer may be just the start of a new era of electric aircraft. Researchers predict fully autonomous planes by 2025.
WATTsUP, electric aircraft, airfield, pilot training, zero emission, flight trainer