MLB used numerical optimization when first considering micro air vehicle designs. Analysis results indicated that maximum wing area (and lift capability) for a given size is critical to achieving performance in an MAV. Circular wing planforms have maximum area for a given size, but have poor aileron effectiveness because the control surfaces are located close to the wing centerline in a region of strong vortical flow. We tested several circular wing designs and found that a slot between the upper and lower wing surfaces restored control effectiveness, but reduced the wing’s internal payload volume. Rudder control can also be used for turning because low AR designs have strong yaw-roll coupling due to side edge wing vortices, but this type of control is very nonlinear with angle of attack.