With the continued move towards autonomy in space of unmanned aerial vehicles (UAVs), the requirements for the integration of state of the art path and mission planning algorithms with collision avoidance systems keep growing. There has been a lot of development in the spaces of mission planning and collision avoidance, while path planning is a broadly understood topic, but integrations of all these concepts into complete systems have been sparse. This thesis attempts to deliver such a system by implementing obstacle avoidance and multiple pathfinding algorithms and integrating them with a mission control expert system. The implementation is then evaluated for multiple performance metrics using an integrated system simulation.