The objective of the present work is to evaluate the static and dynamic stability of the Unmanned Airplane for Ecological Conservation using the inviscid panel code CMARC. This code is capable of analyzing three-dimensional steady and unsteady flow around a complete airplane. The longitudinal aerodynamics was studied by a half-model of 3.616 panels, assuming symmetrical flow conditions. The lateral-directional aerodynamics was investigated using the complete model supposing asymmetric flow conditions. The stability coefficients were calculated and it can be concluded that the airplane is statically stable. Using these coefficients, the longitudinal and lateral-directional equations of motion were written, in order to evaluate the dynamic stability of the vehicle. The eigenvalues for each mode of motion were computed showing a convergent response for each one. Excellent flying qualities were achieved, rating in Level 1 for the Cooper and Harper scale. A comparison was done between the data obtained in the present work and the values obtained by two vortex lattice method codes and an analytical-empirical method. The values associated with longitudinal mode calculated by the different methods agree fairly well, but those ones linked with lateral-directional mode have a poor correlation.