Two architectures for unmanned aerial vehicles (UAVs) and a method for executing a mission plan are provided. One architecture for a UAV includes a flight command and mission execution (FCME) component making strategic decisions, a flight technical control manager (FTCM) making tactical decisions and a vehicle management system (VMS) providing navigational support. The FCME and FTCM execute on one processor and the VMS executes on a separate processor. The second architecture includes redundant processors for executing the FCME and FTCM as well as redundant processors for executing the VMS. The UAV executes a mission plan, which may include flight plan(s), communication plan(s), weapons plan(s), sensor plan(s), and/or contingent flight plan(s). The UAV may control various optical sensors, training sensors, and lights as well.