Motor driven tail
A motor driven tail is usually found on small ready to fly electric helicopters. Rather than derive power for the tail rotor from the main motor, the tail rotor is formed by a small electric motor attached to a fixed-pitch propeller. The tail rotor's thrust is varied not by changing the rotor's pitch but by varying the power to the tail motor, and so controlling the tail rotor's speed.
While cheap and mechanically simple to implement, the motor driven tail has a number of shortcomings.
- Firstly, it is nowhere near as fast to react as a variable pitch tail rotor driven from the helicopter's main motor, so it is harder to maintain the helicopter's heading.
- Because the tail motor is much smaller than the main motor, it generally will not have as much power as a variable pitch tail rotor.
- As the prop is only efficient at moving air in one direction (and most cheap speed controllers don't have a reverse function), turning the helicopter against the direction of the rotor (nose left for most models) is limited to the force developed by the helicopter's torque reaction to the main rotor.
Share your opinion