This paper presents an FPGA based synthesiz able offline UAV local path planner implementation using Evolutionary Algorithms for 3D unknown environments. A Genetic Algorithm is selected as the path planning algorithm and all units of it are executed on a single FPGA board. In this study, Nexys 4 Artix-7 FPGA board is selected as the target device and Xilinx Vivado 2015.4 software is used for synthesis and analysis of HDL design. Local path planner is designed in a way that it has two flight modes: free elevation flight mode and fixed elevation flight mode. Designed FPGA based local path planner which has 74 MHz operating frequency and 62% logic slice utilization is tested into two different unknown environments generated by a LIDAR sensor. Results show that both GAs are efficient path planning algorithms for UAV applications and FPGAs are very suitable platforms for flight planning periphery.