Research on bio-inspired flapping-wing microaerial vehicles (MAVs) has experienced a steady growth over the past two decades. In particular, experiments on insect flight dynamics may provide new solutions for various challenges ranging from morphological design to force control mechanisms. A significant amount of research in this area is focused on modeling and simulation of such dynamics; however, mass of the wings and corresponding inertia effects are often ignored for simplification purposes. In this paper, the MAV is considered to be a structure with three rigid bodies, i.e., a main body and two wings. Wing strokes are limited within the body's transverse plane, though each wing can also passively pitch around its lateral axis. Using the Lagrangian, a dynamic multibody model of this system is developed to «1» analyze the significance of wing mass in flight dynamics and «2» simulate flight control experiments. The employed control approach is based on investigated relationships between mechanical impedance properties of the wing pitch joints and average values of aerodynamic forces. The results suggest that the wings' mass and mechanical impedance properties of the joints can be optimized together to enhance lift/thrust production. In addition, simulations of various flight maneuvers with the optimized model and proposed control approach always demonstrate an agile and stable behavior.