China Helicopter Research and Development Institute
Jingdezhen, Jiangxi province, China
While little is known about the project, Deng Jinghui, chief designer at the China Helicopter Research and Development Institute in Jingdezhen, said that they have added an electric tail rotor to an AVIC AC311 helicopter and trial demonstrations have already taken place. (The Chinese AC311 helicopter is the equivalent of Airbus Helicopters H120 light utility single turbine engine helicopter, formerly known as the EC120 Colibri helicopter).
Replacing a conventional tail rotor with an electric version is our first step in exploring and verifying the technical feasibility of an all-electric helicopter.
Jinghui said their engineers plan to spend about two years to test the performance of electric tail rotor. Once the tail rotor tests are successfully completed, they will then remove the main turbine and replace it with an electric motor and the additional components and software, and see if they can make a successful transformation and validate the changes will extensive testing. Their goal is to have a working electric helicopter within a decade.
The biggest advantage of an electric helicopter, Deng said, is that it will not need a transmission which is not only one of the essential parts in a helicopter but also one of the most sophisticated components in conventional helicopters.
When converting a conventional aircraft to electric, it greatly reduces the empty weight of the aircraft, therefore increasing its range or payload or both. For example, there is the weight of the turbine engine, the transmission, the shaft that turns the rear rotor blade and the rear rotorblade’s gearbox, and don’t forget that the gas tank alone weighs 321 kg,m (707 lbs) in the AVIC AC311 helicopter! On reducing complexity, the engine and transmission has many parts, so when and internal combustion powerplant is eliminated, the aircraft is much less mechanically complex. For example, there is only one moving part in an electric motor.
By converting a combustion powered helicopter into an electric one, there are multiple advantages including reducing the weight of the helicopter, making it less complex, improves control, increases reliability, increases safety, it costs less to produce, it costs less to operate and there are no emissions.
They noted that the success of electric helicopters will depend upon whether engineers can design electric helicopters with the same or better performance and duration abilities as we have with conventional helicopters flying today.