Helicopter

<a href="https://en.wikipedia.org/wiki/Coaxial_rotors" target="_blank" rel="nofollow noopener noreferrer">Coaxial Rotors</a>

A.V.Ramani<a href="https://en.wikipedia.org/wiki/Coaxial_rotors" target="_blank" rel="nofollow noopener noreferrer">Coaxial Rotors</a>

thanks

toy copters mostly fly straight. Real copters need Yaw control. Tail rotor takes that function. Since it is at a distance from the Main rotor Axle we get the lever advantage less force to YAW. Speed and tail rotor blade angle of attack determined the yaw turning radius and direction of turn.

Shaheen MongamMost of the Toy RC helicopters available in market are of having a different rotor mechanism compared to original big helicopters. In toy RC helicopters, there will be two rotor blades rotating in opposite directions, while in real helicopters, there will be one main rotor and a tail rotor (these systems are for cancelling counter action and also for direction controls). Why in big size helicopters, the two rotor systems are not used (which I think is cheaper and simpler)

In case of coaxial rotor, the design of the rotor hub and its assembly is complex. Also, it is more prone to mechanical faults and possible failure.

In RC helicopters, the pitch of the blades is constant while in real world helicopters we should be able to change the pitch of blades for control of flight. Incorporating such designs makes it increasing complex and costly.

Albeit, Coaxial Rotor Helicopters will rule the future though because of its many advantages like minimum vibration, fail safe anti torque system, blade stall etc.