This paper presents an experimental assessment of event-triggered sliding mode control (ET-SMC) on a Quadcopter for trajectory tracking. Sufficient triggering conditions using Lyapunov analysis and a lower bound of inter-event time to avoid Zeno behaviour are derived to ensure robust stability. Real-time flights are performed for tracking constant and time-varying trajectories. Results reveal that while using the proposed controller, there is a significant reduction in the number of updates implying a substantial saving in the computations.