A torque tube is a type of driveshaft used to power the tail rotor of a model helicopter in lieu of a more common notched Gilmer belt used as a tail belt.
Similar in theory to driveshaft systems used on mid-20th Century full-scale automobiles, a model helicopter torque tube relies on a bearing-supported, flexible driveshaft made of carbon fiber or wire contained within the tail boom. Like a belt-driven tail, the torque tube is powered by a jackshaft driven by the tail drive gear with the primary difference being beveled drive gears both at the jackshaft and the tail rotor instead of the notched guide wheels required by a belt.
Torque tubes generate less drag on the motor or engine than a belt and are more durable in normal operation. However, a torque tube system is less tolerant of boom strikes or anything that stops the tail rotor from spinning; the drive gears are highly likely to strip in a crash.
Share your opinion