The objective of this paper is to describe the design and implementation of a small semiautonomous

fixed-wing unmanned air vehicle. In particular we describe the hardware and

software architectures used in the design. We also describe a low weight, low cost autopilot

developed at Brigham Young University and the algorithms associated with the autopilot.

Novel PDA and voice interfaces to the UAV are described. In addition, we overview our

approach to real-time path planning, trajectory generation, and trajectory tracking. The

paper is augmented with movie files that demonstrate the functionality of the UAV and its

control software.