This paper describes the design, development, and operation of a research Unmanned Aerial Vehicle (UAV) system that has been developed at the Georgia Institute of Technology, called the GTMax. This description will include the processes put in place to enable the system to be used for UAV-technology research, including effective flight testing. Research UAVs are characterized by the need for continual checkout of experimental software and hardware. Also, flight-testing can be further leveraged by complementing research results with flight-test validated simulation results for the same experimental UAV platform. The chosen helicopter-based UAV platform (a Yamaha R-Max) is well instrumented, including: differential GPS, inertial measurement unit, sonar altimeter, radar altimeter, and a 3-axis magnetometer. One or two flight processors can be utilized.