This paper presents a trajectory tracking fault-tolerant control strategy inside an autonomous emergency landing architecture to control a quadrotor in case of partial rotor fault. The proposed architecture, which is composed of required hardware and subsystems, aims to ensure a fully autonomous safe landing of the impaired quadrotor to a suitable landing site. The controller strategy, which is tried to be coincident with the proposed emergency landing architecture and the Pixhawk autopilot contains a cascade three-loop structure of adaptive sliding mode and a modified PID algorithm along with a fault detection algorithm. The adaptive sliding mode and the PID algorithms are applied to the fast dynamics of angular velocity rates and the position control of the quadrotor, respectively. A lightweight fault detection algorithm is developed to detect and identify the partial faults of engine using the controller outputs and the filtered angular rates. The simulation results demonstrate that the proposed fault-tolerant controller can control the multi-rotor in partial engine faults with satisfactory tracking performance. The results also demonstrate the effect of fault detection time delay on the overall control performance. [ABSTRACT FROM AUTHOR]