Research in performance evaluation of routing protocols for Flying Ad Hoc Networks (FANETs) focuses on analyzing and comparing the efficiency, scalability, and robustness of routing mechanisms under varying aerial network conditions. Recent studies conduct extensive simulations and real-world experiments to assess metrics such as packet delivery ratio, end-to-end delay, throughput, energy consumption, and link stability. Machine learning–based evaluation frameworks are increasingly used to model dynamic UAV behaviors and optimize routing decisions. Hybrid and mobility-aware routing protocols are tested under different flight patterns, node densities, and altitude variations to determine their adaptability and reliability. These performance evaluation studies provide critical insights into selecting suitable routing schemes for mission-specific FANET applications such as disaster recovery, surveillance, and environmental monitoring, ensuring high communication quality and operational efficiency.