Brushless DC (BLDC) motors serve as integral elements of Unmanned Aerial Vehicles (UAVs), ensuring precise propulsion and maneuverability. In order to improve UAV efficiency and reliability, this paper investigates the development of a sensorless Field-Oriented Control (FOC) system for BLDC motors. The emphasis is on rotor position estimation using the third harmonic component of the back electromotive force (EMF). The absence of brushes and commutators makes BLDC motors particularly suitable for UAV applications due to their reliability and efficiency. Traditional sensor-based FOC methods are widely employed, but the integration of sensors poses challenges in terms of complexity, weight concerns, and potential failure points. This study uses a sensor-free technique, focusing on the third harmonic back EMF for accurate rotor position prediction. The fundamental characteristics of the third harmonic provide a promising avenue for dependable sensorless control, contributing to streamlined UAV designs trying to provide better operational resilience. The feasibility and benefits of using the third harmonic back EMF in sensorless FOC for BLDC motors in UAV applications are investigated in this research. The aim is to develop a strong control technique that improves motor performance, decreases hardware complexity, and meets the particular constraints of the UAV environment. The simulation and analysis of the proposed sensorless FOC system are conducted using MATLAB Simulink and the findings add to the growing body of information aimed at optimizing BLDC motor control for UAVs, promoting progress in the field of unmanned aerial systems.