This is the first of two papers concerning the fluid and structural dynamic characteristics of membrane wing microair vehicles. In this paper, a (three) batten-reinforced fixed-wing membrane microair vehicle is used to determine the effect of membrane prestrain on flutter and limit cycle behavior of fixed-wing membrane microair vehicles. For each configuration tested, flutter and subsequent limit cycle oscillations are measured in wind tunnel tests and predicted using an aeroelastic computational model consisting of a nonlinear finite element model coupled to a vortex lattice solution of the Laplace equation and boundary conditions. Agreement between the predicted and measured onset of limit cycle oscillation is good as is the prediction of the amplitude of the limit cycle at the trailing edge of the lower membrane. A direct correlation between levels of strain and the phase of the membranes during the limit cycle is found in the computation and thought to also occur in the experiment.