A motion tracking system was used to experimentally determine the aerodynamic forces and moments of two micro UAVs. The airplanes have wingspans ranging from approximately 9 to 15 in and fly at Reynolds numbers below 25,000. The motion track provided a time history of the position and attitude and was used to derive the aerodynamic moments and analyze the stability derivatives of the airplanes. A reconfigurable hand-launched glider was used to show results for different wing configurations. In addition to the glider, a small commercially manufactured SU-26xp airplane was used. The longitudinal stability measurements from experimental data showed both airplanes to be more stable than predictions based on geometry. The SU-26xp airplane was used to study the effects of elevator deflection on trim flight conditions. In addition, the lateral stability terms for both airplane were measured. By understanding the stability and control over a range of flight conditions, a better understanding of the control of micro UAVs can be developed.