Contents
Are coaxial rotors better?
A coaxial rotor eliminates the need for a tail rotor and creates a safer, more stable machine. In order to understand how a design with two coaxial rotors far outperforms other helicopters, we have to examine the physics at play.
How do coaxial rotor helicopters turn?
Coaxial rotors are two main rotors mounted on one mast, sharing the same axis of rotation but turning in opposite directions, one on top of the other. The control along the vertical axis is produced as a result of different lifts, thus differential torque, of the two rotor discs.
Why do RC helicopters have 2 rotors?
Why do RC helicopters have two rotors? The dual rotor design on an RC helicopter is to help the vehicle turn. These rotors spin in directions opposite to each other which ends up canceling out each other’s torque force. Once there is no torque force, the helicopter won’t spin around in a certain direction.
What are the advantages and disadvantages of coaxial helicopter design?
Coaxial design is easier to control since changing the speed of one rotor will only change horizontal direction and lift. A helicopter with two separate rotors will turn, lift and point up or down when the rpm of one changes, making a more difficult equilibrium.
How does a coaxial rotor helicopter achieve yaw?
In a helicopter with coaxial rotors there is no tail rotor, but the torque issue remains. Here, it’s resolved by applying equal but opposite torque to each rotor. Lift overall is controlled by changing the Angle of Attack of both rotors. If the same inputs are applied to both rotors then the torque remains balanced.
Are there disadvantages of coaxial rotating rotors?
Turning (yawing) a coaxial at high power settings will be very powerful. (assume a 10% difference in torque between upper and lower rotor) At low power a 10% differential between rotors will be correspondingly low.
What are the disadvantages of helicopter with two rotors?
A helicopter with two separate rotors will turn, lift and point up or down when the rpm of one changes, making a more difficult equilibrium. Can lift more weight. The axis is much more difficult to design, manufacture and maintain. Also the gearbox. Needs a more powerful engine.