The objective of the proposed research project is to effectively control the UAV rotorcraft for trajectory tracking and feature tracking, such as is used in power line inspection, turbulent atmospheric conditions, and with varying UAV payload. The dynamic nonlinear equations of UAV subsystems are combined and presented in canonical/strict feedback form, which enables the application of backstepping techniques. The Lyapunov control function is then formed following dynamic error formulation. Based on Lyapunov stability criteria, control and adaptation laws can be established that yield stable error dynamics and parameter update. Disturbances from the environment acting on the UAV are tackled by integrating the controller with disturbance observer in compensating the translational or angular velocity variation on the UAV due to disturbance. The control system is broken into attitude control and position control where the attitude controller is considered as the inner loop control and position controller as the outer loop control. According to the reference position given, the position controller will output the corresponding desired attitude of the fuselage. That value, in turn, acts as a reference input value to the attitude controller, where an appropriate cyclic pitch control is produced.