Note-This class includes miscellaneous component parts specifically designed for, and used exclusively in, helicopter drive mechanisms and rotor blades when not specifically classified elsewhere in the FSC indexes.

Includes Helicopter dynamic components and specially designed parts that transmit power from the aircraft power plant to the rotary wing and rotary rudder. Also included in this class are Rotors; Blades; Rotor Blade, Trim, Tabs; Blade Sets; Yokes; Clutches and Transmissions.

Excludes Propellers (FSC 1610); Rotor Brake Systems Components (FSC 1630); Rotor Blade Hydraulic Folding System Components (FSC 1650); Hydraulic Servo System Components (FSC 1650).