The typical structure of the Eckasha-32 helicopter transmission with a combination of the fixed axis gear train and the differential gear train with the character of the single input and double output is stuchied
it’s significant for the development of the coaxial counter- rotating twin- rotor helicopter. In order to avoid lowering the transmission efficiency caused by the cycle power flow
the cycle power flow of the transmission is studied
the factors of the cycle power flow and the transimission power distribution table are obatained. The results can provide the basis for the design of the transmission system of the helicopter.