Video

Consider this. The tail has to quickly respond on the commands of the gyro and the rudder/yaw commands fed by the user. A motor driven tail has to rely on "quick" motor speed changes for a responsive yaw control. Speed changes has to be "quick" on both spooling up (counteracting torque for a positive yaw) and spooling down (deacceleration for allowing the main rotor torque to take over for a quick negative yaw). The problem with a motor driven tail is that the speed change is not that quick as the tail has to "accelerate" or "deaccelerate" first before the desired speed is achieved. The acceleration/deacceleration factor is heavily dependent on the weight of the tail rotor blades and the motor's shaft and armature. With a "dual motor" mod , you achieve a quick speed change but still it has to accelerate and it also increases the overall weight including the armature thus the opposite yaw would be slower unless you apply some sort of "braking" mechanism in there in order to have the same quick response effect on spooling down. Some would even use a "brushless tail motor" or a ducted fan mod sort to speak but those motors need some time to accelerate and deaccelerate as well thus yaw control would still be a problem plus the fact the a duct itseld would even add a certain amount of momentum on the tail causing yaw overshoots and undershoots. Well, the best tail rotor response would still be a belt drive option as you will only deal with a constant tail blade rotational speed, and you would only rely on the pitch of the blades to counteract the torque and with these much quicker pitch changes, no acceleration/deacceleration factor will affect the perfomance of the tail and your heli's heading will be tight. But what about helis without a belt drive ? I am presenting this concept of having still a motor driven tail but with a constant speed and the yaw is still dictated by the pitch of the rotor blades instead of the usual motor speed changes. This video demonstrates this idea using a HoneyBee CP2 Carbon Fiber Tail mounted with 1100KV Brushless Motor. An ESky Belt CP tail assembly was used. The motor and BeltCp tail was mounted on the CarbonFiber Shaft using a CP2 Blade Grip/Holder. Build Log Here; http://www.rcgroups.com/forums/showth...